Insuring Consumption Using Income-Linked Assets Andreas Fuster and - - PowerPoint PPT Presentation

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Insuring Consumption Using Income-Linked Assets Andreas Fuster and - - PowerPoint PPT Presentation

Introduction Two-Period Example Life-Cycle Model Discussion Insuring Consumption Using Income-Linked Assets Andreas Fuster and Paul Willen Harvard University and Federal Reserve Bank of Boston Conference on Household Finance and


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Introduction Two-Period Example Life-Cycle Model Discussion

Insuring Consumption Using Income-Linked Assets

Andreas Fuster and Paul Willen

Harvard University and Federal Reserve Bank of Boston

Conference on Household Finance and Macroeconomics Banco de Espa˜ na, Madrid October 16, 2009

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 1 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Introduction

Human capital is the largest component of total household wealth for much of life It is also risky: income volatility is high (and supposedly has increased

  • ver past decades)

Much evidence that this leads to consumption volatility, due to imperfect risk-sharing Not too surprising: risk-sharing is generally difficult because of

informational asymmetries (moral hazard) limited commitment Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 2 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Introduction

Yet, part of human capital risk is group-specific and cross-sectional Such risk could be hedged through financial assets with payoffs linked to group-level income indices

and without requiring a risk premium for aggregate risk

Shiller (2003) and others have advocated the introduction of new financial assets to allow households to better insure against human capital risk (among others) Our goal is to evaluate the potential use and usefulness of such assets for households’ income risk management over the life cycle

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 3 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

Shiller proposes six types of insurance:

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

Shiller proposes six types of insurance:

1 Livelihood insurance Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

Shiller proposes six types of insurance:

1 Livelihood insurance 2 Home equity insurance Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

Shiller proposes six types of insurance:

1 Livelihood insurance 2 Home equity insurance 3 Macro markets Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

Shiller proposes six types of insurance:

1 Livelihood insurance 2 Home equity insurance 3 Macro markets 4 Income-linked loans Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

Shiller proposes six types of insurance:

1 Livelihood insurance 2 Home equity insurance 3 Macro markets 4 Income-linked loans 5 Inequality insurance Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

Shiller proposes six types of insurance:

1 Livelihood insurance 2 Home equity insurance 3 Macro markets 4 Income-linked loans 5 Inequality insurance 6 Intergenerational social security Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

1 Livelihood insurance 3 Macro markets 4 Income-linked loans

In this paper, we consider (an example of) 1/3, and 4

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

“Imagining the social and economic achievement that could come from a new financial order is difficult because we have not seen such an alternate world.”

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 5 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

“Imagining the social and economic achievement that could come from a new financial order is difficult because we have not seen such an alternate world.” ⇒ Need to use a model

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 5 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

“Imagining the social and economic achievement that could come from a new financial order is difficult because we have not seen such an alternate world.” ⇒ Need to use a model “Making such [assets] more widely available would entail work from both the private sector and the government.”

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 5 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Motivation

“Imagining the social and economic achievement that could come from a new financial order is difficult because we have not seen such an alternate world.” ⇒ Need to use a model “Making such [assets] more widely available would entail work from both the private sector and the government.” ⇒ How large are the benefits? Is it worth it?

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 5 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we do

Consider a life-cycle portfolio choice model with realistic borrowing and investment opportunities

Key feature: borrowing rate > lending rate Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 6 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we do

Consider a life-cycle portfolio choice model with realistic borrowing and investment opportunities

Key feature: borrowing rate > lending rate

Introduce new assets: income-hedging instrument or income-linked loans

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 6 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we do

Consider a life-cycle portfolio choice model with realistic borrowing and investment opportunities

Key feature: borrowing rate > lending rate

Introduce new assets: income-hedging instrument or income-linked loans

IHI: limited liability asset with returns negatively correlated with

income shock

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 6 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we do

Consider a life-cycle portfolio choice model with realistic borrowing and investment opportunities

Key feature: borrowing rate > lending rate

Introduce new assets: income-hedging instrument or income-linked loans

IHI: limited liability asset with returns negatively correlated with

income shock

ILL: loan with required repayment positively correlated with income

shock

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 6 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we do

Consider a life-cycle portfolio choice model with realistic borrowing and investment opportunities

Key feature: borrowing rate > lending rate

Introduce new assets: income-hedging instrument or income-linked loans

IHI: limited liability asset with returns negatively correlated with

income shock

ILL: loan with required repayment positively correlated with income

shock

Look at demand for these assets over the life cycle, and predicted welfare gains that their availability would generate for households

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 6 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we find

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 7 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we find

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 7 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we find

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL generally more beneficial than IHI Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 7 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we find

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL generally more beneficial than IHI Correlation with income shocks Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 7 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we find

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL generally more beneficial than IHI Correlation with income shocks Volatility Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 7 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we find

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL generally more beneficial than IHI Correlation with income shocks Volatility 2 The income-linked assets (in particular ILL) can produce

non-negligible welfare gains (>1%)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 7 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

What we find

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL generally more beneficial than IHI Correlation with income shocks Volatility 2 The income-linked assets (in particular ILL) can produce

non-negligible welfare gains (>1%)

3 But difficult to reduce a large fraction of the welfare costs from labor

income risk with the assets we consider

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 7 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

“Asset Pricing”

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 8 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

“Asset Pricing”

What would be...

E(r)? σ(r)? corr(r, income)? Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 8 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

“Asset Pricing”

What would be...

E(r)? σ(r)? corr(r, income)?

We remain relatively agnostic & try various assumptions

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 8 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

“Asset Pricing”

What would be...

E(r)? σ(r)? corr(r, income)?

We remain relatively agnostic & try various assumptions Baseline assumption for |corr(r, income)|: 0.5, based on CPS

  • ccupation-level income series (Davis et al. 2009)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 8 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

“Asset Pricing”

What would be...

E(r)? σ(r)? corr(r, income)?

We remain relatively agnostic & try various assumptions Baseline assumption for |corr(r, income)|: 0.5, based on CPS

  • ccupation-level income series (Davis et al. 2009)

Baseline assumption for E(r): “actuarial fairness”

E(˜

rIHI) = rl (risk-free saving rate)

E(˜

rILL) = rb (risk-free borrowing rate)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 8 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

“Asset Pricing”

What would be...

E(r)? σ(r)? corr(r, income)?

We remain relatively agnostic & try various assumptions Baseline assumption for |corr(r, income)|: 0.5, based on CPS

  • ccupation-level income series (Davis et al. 2009)

Baseline assumption for E(r): “actuarial fairness”

E(˜

rIHI) = rl (risk-free saving rate)

E(˜

rILL) = rb (risk-free borrowing rate)

This assumes that risks are cross-sectional (not aggregate), and in that sense stacks the deck in favor of these assets

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 8 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Related Literature

Quantitative dynamic macro models that consider welfare costs of income shocks

Storesletten, Telmer, Yaron (2004), Heathcote, Storesletten, Violante

(2008)

Risk-sharing and partial insurance

Attanasio and Davis (1996), Krueger and Perri (2006), Blundell et al.

(2008)

Optimal portfolio choice over the life cycle

Cocco, Gomes, Maenhout (2005), Gomes and Michaelides (2005) Our model builds on Davis, K¨

ubler, Willen (2006)

Close in spirit: De Jong, Driessen, Van Hemert (2008) on housing

futures; Cocco and Gomes (2009) on longevity bonds

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 9 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Motivation Overview Related Literature

Outline

1 Two-period example Goal: provide intuition for what determines demand for and welfare

gains from income-linked assets

2 Life-cycle model Goal: show that intuition carries over; quantitatively assess use and

usefulness of assets over life cycle

3 Discussion / Conclusion Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 10 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Two-Period Example: Setup

CRRA=2 investor lives for 2 periods Objective: max u(c1) + Eu(c2) Has some cash-on-hand in period 1 Receives stochastic income in period 2 with mean 8

Y2 ∈ {5.4, 8, 10.6} with p = {1/6, 2/3, 1/6} Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 11 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Two-Period Example: Setup

CRRA=2 investor lives for 2 periods Objective: max u(c1) + Eu(c2) Has some cash-on-hand in period 1 Receives stochastic income in period 2 with mean 8

Y2 ∈ {5.4, 8, 10.6} with p = {1/6, 2/3, 1/6}

Benchmark: Investor can...

save at rl = 2% invest in equity with E(˜

re) = 6% and σ(˜ re) = 16%

borrow at rb = 8% Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 11 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Two-Period Example: Setup

CRRA=2 investor lives for 2 periods Objective: max u(c1) + Eu(c2) Has some cash-on-hand in period 1 Receives stochastic income in period 2 with mean 8

Y2 ∈ {5.4, 8, 10.6} with p = {1/6, 2/3, 1/6}

Benchmark: Investor can...

save at rl = 2% invest in equity with E(˜

re) = 6% and σ(˜ re) = 16%

borrow at rb = 8%

Constraints: b, l, e ≥ 0 No default in model, so positive lower bound on Y2 important (otherwise no borrowing possible)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 11 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Benchmark

E(Y2) = 8, rl = 0.02, rb = 0.08, E(˜ re) = 0.06, σe = 0.16

Cash-on-hand Asset holding Benchmark: Optimal Asset Holdings Borrowing Equity 2 4 6 8 10 12 14 16

  • 4
  • 3
  • 2
  • 1

1 2 3 4

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 12 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Income-Hedging Instrument

Now, investor can additionally invest in income-hedging instrument E(˜ rIHI) = rl = 2% σ(˜ rIHI) = 25% corr(˜ rIHI, Y2) = –0.5 ⇒ IHI provides some insurance benefits, but not perfect insurance

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 13 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

IHI: Optimal Asset Holdings

Cash-on-hand Asset holding With Income-Hedging Instrument Borrowing Equity Income-hedging instrument ↓ 2 4 6 8 10 12 14 16

  • 4
  • 3
  • 2
  • 1

1 2 3 4

Optimal IHI holdings nonlinear in cash-on-hand

Over some range of

cash-on-hand, no IHI holdings

Relatively poor and relatively

rich investors find IHI most attractive

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 14 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

IHI: Optimal Asset Holdings

Cash-on-hand Asset holding With Income-Hedging Instrument Borrowing Equity Income-hedging instrument 2 4 6 8 10 12 14 16

  • 4
  • 3
  • 2
  • 1

1 2 3 4

Optimal IHI holdings nonlinear in cash-on-hand

Over some range of

cash-on-hand, no IHI holdings

Relatively poor and relatively

rich investors find IHI most attractive

Compared with benchmark:

Borrowing by poor investor

increases

Equity holdings by rich

decrease

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 14 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

What determines optimal asset holdings?

How much a households holds of each asset depends on the risk-adjusted returns EQ( ˜ Ri) of all assets

EQ( ˜

Ri) higher if i pays off a lot in states of the world with high u(c)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 15 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

What determines optimal asset holdings?

How much a households holds of each asset depends on the risk-adjusted returns EQ( ˜ Ri) of all assets

EQ( ˜

Ri) higher if i pays off a lot in states of the world with high u(c)

For IHI, have that EQ( ˜ RIHI) > E( ˜ RIHI) = Rl

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 15 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

What determines optimal asset holdings?

How much a households holds of each asset depends on the risk-adjusted returns EQ( ˜ Ri) of all assets

EQ( ˜

Ri) higher if i pays off a lot in states of the world with high u(c)

For IHI, have that EQ( ˜ RIHI) > E( ˜ RIHI) = Rl So if household could borrow at Rl, would always hold IHI

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 15 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

What determines optimal asset holdings?

How much a households holds of each asset depends on the risk-adjusted returns EQ( ˜ Ri) of all assets

EQ( ˜

Ri) higher if i pays off a lot in states of the world with high u(c)

For IHI, have that EQ( ˜ RIHI) > E( ˜ RIHI) = Rl So if household could borrow at Rl, would always hold IHI However, for households who must borrow at higher rate, only buy IHI if EQ( ˜ RIHI) ≥ Rb

What determines whether a household borrows? Expected future

consumption growth ⇒ borrow if relatively poor today

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 15 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

What determines optimal asset holdings?

How much a households holds of each asset depends on the risk-adjusted returns EQ( ˜ Ri) of all assets

EQ( ˜

Ri) higher if i pays off a lot in states of the world with high u(c)

For IHI, have that EQ( ˜ RIHI) > E( ˜ RIHI) = Rl So if household could borrow at Rl, would always hold IHI However, for households who must borrow at higher rate, only buy IHI if EQ( ˜ RIHI) ≥ Rb

What determines whether a household borrows? Expected future

consumption growth ⇒ borrow if relatively poor today

And for households who save, IHI “competes” against equity ⇒ only buy IHI if EQ( ˜ RIHI) ≥ EQ( ˜ Re)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 15 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

IHI: Optimal Asset Holdings

Cash-on-hand Asset holding With Income-Hedging Instrument Borrowing Equity Income-hedging instrument 2 4 6 8 10 12 14 16

  • 4
  • 3
  • 2
  • 1

1 2 3 4

Optimal IHI holdings nonlinear in cash-on-hand

Over some range of

cash-on-hand, no IHI holdings

Relatively poor and relatively

rich investors find IHI most attractive

Compared with benchmark:

Borrowing by poor investor

increases

Equity holdings by rich

decrease

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 16 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Bottom line: Whether and how extensively investor will use income-linked asset will depend on

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 17 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Bottom line: Whether and how extensively investor will use income-linked asset will depend on

his financial wealth Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 17 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Bottom line: Whether and how extensively investor will use income-linked asset will depend on

his financial wealth his life-cycle income profile Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 17 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Bottom line: Whether and how extensively investor will use income-linked asset will depend on

his financial wealth his life-cycle income profile the risk-adjusted returns of other investment opportunities Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 17 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Bottom line: Whether and how extensively investor will use income-linked asset will depend on

his financial wealth his life-cycle income profile the risk-adjusted returns of other investment opportunities

The welfare gain from an income-linked asset will depend on its (opportunity) cost

High for IHI Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 17 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Income-Linked Loan

Now, instead, investor can additionally borrow through income-linked loan E(˜ rILL) = rb = 8% σ(˜ rILL) = 25% corr(˜ rILL, Y2) = +0.5

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 18 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

ILL: Optimal Asset Holdings

Cash-on-hand Asset holding With Income-Linked Loan Borrowing

Equity

Income-linked loan 2 4 6 8 10 12 14 16

  • 4
  • 3
  • 2
  • 1

1 2 3 4

Optimal ILL borrowing nonlinear in cash-on-hand

Goes to zero as cash-on-hand

increases

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 19 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

ILL: Optimal Asset Holdings

Cash-on-hand Asset holding With Income-Linked Loan Borrowing

Equity

Income-linked loan 2 4 6 8 10 12 14 16

  • 4
  • 3
  • 2
  • 1

1 2 3 4

Optimal ILL borrowing nonlinear in cash-on-hand

Goes to zero as cash-on-hand

increases

Compared with benchmark:

ILL substitutes for unsecured

borrowing

Over some range, additional

borrowing & investment in equity (EQ( ˜ RILL) = EQ( ˜ Re), even though E( ˜ RILL) > E( ˜ Re))

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 19 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Welfare Gains over Benchmark

Cash-on-hand Gain in certainty-equivalent consumption (in %) Welfare gains from the two assets ILL IHI 2 4 6 8 10 12 14 16 0.5 1 1.5 2 2.5

Welfare measure: certainty-equivalent consumption ¯ c s.th. u(c1) + Eu(c2) = 2u(¯ c)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 20 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Welfare Gains over Benchmark

Cash-on-hand Gain in certainty-equivalent consumption (in %) Welfare gains from the two assets ILL IHI 2 4 6 8 10 12 14 16 0.5 1 1.5 2 2.5

Welfare measure: certainty-equivalent consumption ¯ c s.th. u(c1) + Eu(c2) = 2u(¯ c) ILL provides larger gains over wide range of cash-on-hand

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 20 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Welfare Gains over Benchmark

Cash-on-hand Gain in certainty-equivalent consumption (in %) Welfare gains from the two assets ILL IHI 2 4 6 8 10 12 14 16 0.5 1 1.5 2 2.5

Welfare measure: certainty-equivalent consumption ¯ c s.th. u(c1) + Eu(c2) = 2u(¯ c) ILL provides larger gains over wide range of cash-on-hand Intuitively: lower (opportunity) cost

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 20 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Benchmark Income-Hedging Instrument Income-Linked Loan Welfare

Welfare Gains over Benchmark

Cash-on-hand Gain in certainty-equivalent consumption (in %) Welfare gains from the two assets ILL IHI 2 4 6 8 10 12 14 16 0.5 1 1.5 2 2.5

Welfare measure: certainty-equivalent consumption ¯ c s.th. u(c1) + Eu(c2) = 2u(¯ c) ILL provides larger gains over wide range of cash-on-hand Intuitively: lower (opportunity) cost Welfare gain small as compared to having Y2=8 for sure

9.21% for c-o-h=0 2.81% for c-o-h=5 1.40% for c-o-h=10 Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 20 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 21 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 21 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life Can trade three or four financial assets.

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 21 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life Can trade three or four financial assets.

equity with stochastic net return ˜

re,

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 21 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life Can trade three or four financial assets.

equity with stochastic net return ˜

re,

save at a net risk-free rate rl, Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 21 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life Can trade three or four financial assets.

equity with stochastic net return ˜

re,

save at a net risk-free rate rl, engage in uncollateralized borrowing at the rate rb > rl Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 21 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life Can trade three or four financial assets.

equity with stochastic net return ˜

re,

save at a net risk-free rate rl, engage in uncollateralized borrowing at the rate rb > rl

and either

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 21 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life Can trade three or four financial assets.

equity with stochastic net return ˜

re,

save at a net risk-free rate rl, engage in uncollateralized borrowing at the rate rb > rl

and either

invest in income-hedging instrument with stochastic net return ˜

rIHI,

  • r

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 21 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life Can trade three or four financial assets.

equity with stochastic net return ˜

re,

save at a net risk-free rate rl, engage in uncollateralized borrowing at the rate rb > rl

and either

invest in income-hedging instrument with stochastic net return ˜

rIHI,

  • r

borrow through income-linked loans at the stochastic rate ˜

rILL.

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 21 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life Can trade three or four financial assets.

equity with stochastic net return ˜

re,

save at a net risk-free rate rl, engage in uncollateralized borrowing at the rate rb > rl

and either

invest in income-hedging instrument with stochastic net return ˜

rIHI,

  • r

borrow through income-linked loans at the stochastic rate ˜

rILL.

No explicit limit on borrowing; have to be able to repay with prob. 1

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 21 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life Can trade three or four financial assets.

equity with stochastic net return ˜

re,

save at a net risk-free rate rl, engage in uncollateralized borrowing at the rate rb > rl

and either

invest in income-hedging instrument with stochastic net return ˜

rIHI,

  • r

borrow through income-linked loans at the stochastic rate ˜

rILL.

No explicit limit on borrowing; have to be able to repay with prob. 1 Short-sale constraints: et ≥ 0, lt ≥ 0, bt ≥ 0, IHIt ≥ 0, ILLt ≥ 0

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Life-Cycle Model

Households in partial equilibrium, live from 20 to 80, retire at 65 Receive stochastic income Yt during working life Can trade three or four financial assets.

equity with stochastic net return ˜

re,

save at a net risk-free rate rl, engage in uncollateralized borrowing at the rate rb > rl

and either

invest in income-hedging instrument with stochastic net return ˜

rIHI,

  • r

borrow through income-linked loans at the stochastic rate ˜

rILL.

No explicit limit on borrowing; have to be able to repay with prob. 1 Short-sale constraints: et ≥ 0, lt ≥ 0, bt ≥ 0, IHIt ≥ 0, ILLt ≥ 0 Finite-horizon dynamic program, solved computationally

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Our Strategy

Start with model that only features e, l, b

Calibrate to match wealth/income before retirement Demonstrate that this model makes reasonable predictions regarding

equity holdings and borrowing over the LC

Use this as benchmark model Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 22 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Our Strategy

Start with model that only features e, l, b

Calibrate to match wealth/income before retirement Demonstrate that this model makes reasonable predictions regarding

equity holdings and borrowing over the LC

Use this as benchmark model

Then, add either income-hedging instrument or income-linked loan, with various assumptions about return process

Look at effect on asset holdings over the LC Evaluate welfare gain from having access to new asset Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 22 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income Process

Income process as standard in consumption/pf choice literature (following Gourinchas-Parker 2002, Cocco et al. 2005): log(Yit) = ˜ yt = dt + ˜ ηt + ˜ εt

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income Process

Income process as standard in consumption/pf choice literature (following Gourinchas-Parker 2002, Cocco et al. 2005): log(Yit) = ˜ yt = dt + ˜ ηt + ˜ εt Deterministic component dt

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income Process

Income process as standard in consumption/pf choice literature (following Gourinchas-Parker 2002, Cocco et al. 2005): log(Yit) = ˜ yt = dt + ˜ ηt + ˜ εt Deterministic component dt Permanent (random walk) component ˜ ηt = ηt−1 + ˜ ut, with ˜ ut ∼ N(−σ2

u/2, σ2 u)

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income Process

Income process as standard in consumption/pf choice literature (following Gourinchas-Parker 2002, Cocco et al. 2005): log(Yit) = ˜ yt = dt + ˜ ηt + ˜ εt Deterministic component dt Permanent (random walk) component ˜ ηt = ηt−1 + ˜ ut, with ˜ ut ∼ N(−σ2

u/2, σ2 u)

Temporary component ˜ εt ∼ N(−σ2

ε/2, σ2 ε)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 23 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income Process

Income process as standard in consumption/pf choice literature (following Gourinchas-Parker 2002, Cocco et al. 2005): log(Yit) = ˜ yt = dt + ˜ ηt + ˜ εt Deterministic component dt Permanent (random walk) component ˜ ηt = ηt−1 + ˜ ut, with ˜ ut ∼ N(−σ2

u/2, σ2 u)

Temporary component ˜ εt ∼ N(−σ2

ε/2, σ2 ε)

Shocks are effectively bounded; no zero-income temporary shock

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 23 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income Process

Income process as standard in consumption/pf choice literature (following Gourinchas-Parker 2002, Cocco et al. 2005): log(Yit) = ˜ yt = dt + ˜ ηt + ˜ εt Deterministic component dt Permanent (random walk) component ˜ ηt = ηt−1 + ˜ ut, with ˜ ut ∼ N(−σ2

u/2, σ2 u)

Temporary component ˜ εt ∼ N(−σ2

ε/2, σ2 ε)

Shocks are effectively bounded; no zero-income temporary shock Retirement income: ˜ yt = log(λ) + dtR + ηtR, t > tR

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 23 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income Process

Use parameters from Cocco et al. for HS grads: σu =0.103, σε =0.272, λ =0.682. Enter at 20, retire at 65, die at 80.

←Mean Income over the Lifecycle (Thousands of 1992 USD) age 20 30 40 50 60 70 80 10 15 20 25 30 35 40 45 Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 24 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income Process

Use parameters from Cocco et al. for HS grads: σu =0.103, σε =0.272, λ =0.682. Enter at 20, retire at 65, die at 80.

←Mean ← One realization Income over the Lifecycle (Thousands of 1992 USD) age 20 30 40 50 60 70 80 10 15 20 25 30 35 40 45 Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 24 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Other Parameters for Benchmark

CRRA utility with curvature γ =2 Taste-shifter s.th. consumption drops 10% at retirement Risk-free saving rate: rl =0.02 Risk-free borrowing rate: rb =0.08 (Davis et al. 2006) Equity returns: E(˜ re) =0.06, σe =0.16 Discount factor: β =0.936. Chosen to match W/Y =2.6 of households with head aged 50 to 59 (Laibson et al. 2007)

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Benchmark Results

Investment and Borrowing over the LC (means) Thousands of 1992 USD age Equity Borrowing 20 30 40 50 60 70 80

  • 10

10 20 30 40 50 60 70 80 Borrowing & Stock Market Participation over the LC % of households age ← Borrowing ← Equity 20 30 40 50 60 70 80 10 20 30 40 50 60 70 80 90 100

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Benchmark Results

Investment and Borrowing over the LC (means) Thousands of 1992 USD age Equity Borrowing 20 30 40 50 60 70 80

  • 10

10 20 30 40 50 60 70 80 Borrowing & Stock Market Participation over the LC % of households age ← Borrowing ← Equity 20 30 40 50 60 70 80 10 20 30 40 50 60 70 80 90 100

Successes: general pattern of borrowing and risky asset holdings (and participation) over the LC Failures: no bond holdings, and almost no borrowing late in life

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income-Hedging Instrument

Add IHI to benchmark setting. Parameters: rl =0.02, rb =0.08, E(˜ re) =0.06, σe =0.16

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 27 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income-Hedging Instrument

Add IHI to benchmark setting. Parameters: rl =0.02, rb =0.08, E(˜ re) =0.06, σe =0.16 E(˜ rIHI) = rl =0.02

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income-Hedging Instrument

Add IHI to benchmark setting. Parameters: rl =0.02, rb =0.08, E(˜ re) =0.06, σe =0.16 E(˜ rIHI) = rl =0.02 corr(˜ rIHI, ˜ u) = {–0.25,–0.5,–0.75,–1}

Return negatively correlated with permanent shock to income Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 27 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income-Hedging Instrument

Add IHI to benchmark setting. Parameters: rl =0.02, rb =0.08, E(˜ re) =0.06, σe =0.16 E(˜ rIHI) = rl =0.02 corr(˜ rIHI, ˜ u) = {–0.25,–0.5,–0.75,–1}

Return negatively correlated with permanent shock to income

σ(˜ rIHI) = {0.3,0.5}

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income-Hedging Instrument

Add IHI to benchmark setting. Parameters: rl =0.02, rb =0.08, E(˜ re) =0.06, σe =0.16 E(˜ rIHI) = rl =0.02 corr(˜ rIHI, ˜ u) = {–0.25,–0.5,–0.75,–1}

Return negatively correlated with permanent shock to income

σ(˜ rIHI) = {0.3,0.5} Focus on welfare gains from introducing IHI (in paper, look at

LC profiles in

detail)

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Welfare Gains from IHI

Correlation Gain in CE consumption (% over Benchmark)

σ = 0.3 σ = 0.5

  • 0.25
  • 0.5
  • 0.75
  • 1

1 2 3 Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 28 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Welfare Gains from IHI

Correlation Gain in CE consumption (% over Benchmark)

σ = 0.3 σ = 0.5

  • 0.25
  • 0.5
  • 0.75
  • 1

1 2 3

Compare to gain from reducing permanent income shock variance by 25%: 3.5% gain from eliminating all income risk: 16.4%

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IHI: Conclusions

Unless returns very highly correlated with income shock and very volatile, IHI not very useful

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 29 / 38

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IHI: Conclusions

Unless returns very highly correlated with income shock and very volatile, IHI not very useful Too “expensive” for young households, who would benefit most from hedge

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

IHI: Conclusions

Unless returns very highly correlated with income shock and very volatile, IHI not very useful Too “expensive” for young households, who would benefit most from hedge Richer (older) households hold more of IHI, but at expense of equity

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

IHI: Conclusions

Unless returns very highly correlated with income shock and very volatile, IHI not very useful Too “expensive” for young households, who would benefit most from hedge Richer (older) households hold more of IHI, but at expense of equity Welfare gains convex in corr(˜ rIHI, ˜ u) (and even in corr2)

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Income-Linked Loans

Now instead add ILL to benchmark setting. Parameters: rl =0.02, rb=0.08, E(˜ re) =0.06, σe =0.16

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 30 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income-Linked Loans

Now instead add ILL to benchmark setting. Parameters: rl =0.02, rb=0.08, E(˜ re) =0.06, σe =0.16 E(˜ rILL) = rb =0.08

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 30 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income-Linked Loans

Now instead add ILL to benchmark setting. Parameters: rl =0.02, rb=0.08, E(˜ re) =0.06, σe =0.16 E(˜ rILL) = rb =0.08 corr(˜ rILL, ˜ u) = {0.25,0.5,0.75,1}

Rate positively correlated with permanent shock to income Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 30 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

Income-Linked Loans

Now instead add ILL to benchmark setting. Parameters: rl =0.02, rb=0.08, E(˜ re) =0.06, σe =0.16 E(˜ rILL) = rb =0.08 corr(˜ rILL, ˜ u) = {0.25,0.5,0.75,1}

Rate positively correlated with permanent shock to income

σ(˜ rILL) = {0.3,0.5}

LC profiles Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 30 / 38

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Welfare Gains from ILL

Correlation Gain in CE consumption (% over Benchmark) σ = 0.3

σ = 0.5

0.25 0.5 0.75 1 1 2 3 4 5 6 7 8 9 10 Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 31 / 38

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ILL: Conclusions

ILL offer more potential for welfare gains than IHI

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 32 / 38

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ILL: Conclusions

ILL offer more potential for welfare gains than IHI

Even for relatively moderate ρ, σ Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 32 / 38

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ILL: Conclusions

ILL offer more potential for welfare gains than IHI

Even for relatively moderate ρ, σ

Young households (who would borrow anyway) would use it extensively and benefit from improved insurance

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Introduction Two-Period Example Life-Cycle Model Discussion Setup Benchmark Results Income-Hedging Instrument Income-Linked Loans

ILL: Conclusions

ILL offer more potential for welfare gains than IHI

Even for relatively moderate ρ, σ

Young households (who would borrow anyway) would use it extensively and benefit from improved insurance They invest part of their ILL borrowing in high-return equity

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ILL: Conclusions

ILL offer more potential for welfare gains than IHI

Even for relatively moderate ρ, σ

Young households (who would borrow anyway) would use it extensively and benefit from improved insurance They invest part of their ILL borrowing in high-return equity Yet, still far from hypothetical welfare gain achieved by reducing income risk to zero

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 32 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Alternative Investment Option

Our model does not generate enough (any) riskfree asset holdings

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 33 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Alternative Investment Option

Our model does not generate enough (any) riskfree asset holdings Consequence: may understate benefits from IHI; overstate benefits from ILL

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Alternative Investment Option

Our model does not generate enough (any) riskfree asset holdings Consequence: may understate benefits from IHI; overstate benefits from ILL Check: version of the model where agent can only invest in 50/50 stocks-bonds fund (expected return (E(˜ re) + rl)/2, st. dev. 0.5σe)

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Alternative Investment Option

Our model does not generate enough (any) riskfree asset holdings Consequence: may understate benefits from IHI; overstate benefits from ILL Check: version of the model where agent can only invest in 50/50 stocks-bonds fund (expected return (E(˜ re) + rl)/2, st. dev. 0.5σe) Set β = 0.947 to match W/Y

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 33 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Alternative Investment Option

Our model does not generate enough (any) riskfree asset holdings Consequence: may understate benefits from IHI; overstate benefits from ILL Check: version of the model where agent can only invest in 50/50 stocks-bonds fund (expected return (E(˜ re) + rl)/2, st. dev. 0.5σe) Set β = 0.947 to match W/Y Gain from IHI with ρ = –0.5 and σ = 0.5 is now 0.33% instead of 0.04%

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Alternative Investment Option

Our model does not generate enough (any) riskfree asset holdings Consequence: may understate benefits from IHI; overstate benefits from ILL Check: version of the model where agent can only invest in 50/50 stocks-bonds fund (expected return (E(˜ re) + rl)/2, st. dev. 0.5σe) Set β = 0.947 to match W/Y Gain from IHI with ρ = –0.5 and σ = 0.5 is now 0.33% instead of 0.04% Gain from ILL with ρ = +0.5 and σ = 0.5 is now 0.85% instead of 1.36%

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Alternative Investment Option

Our model does not generate enough (any) riskfree asset holdings Consequence: may understate benefits from IHI; overstate benefits from ILL Check: version of the model where agent can only invest in 50/50 stocks-bonds fund (expected return (E(˜ re) + rl)/2, st. dev. 0.5σe) Set β = 0.947 to match W/Y Gain from IHI with ρ = –0.5 and σ = 0.5 is now 0.33% instead of 0.04% Gain from ILL with ρ = +0.5 and σ = 0.5 is now 0.85% instead of 1.36% ⇒ ILL still generates larger welfare gain than IHI, but difference smaller

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Borrowing Cost

We assume an interest rate wedge between borrowing and lending of 6%, based on Davis et al. (2006)

Adjust for tax considerations and charge-offs ⇒ remaining wedge due

to transaction costs etc.

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Borrowing Cost

We assume an interest rate wedge between borrowing and lending of 6%, based on Davis et al. (2006)

Adjust for tax considerations and charge-offs ⇒ remaining wedge due

to transaction costs etc.

What happens if households had access to cheaper borrowing, at 5%?

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Borrowing Cost

We assume an interest rate wedge between borrowing and lending of 6%, based on Davis et al. (2006)

Adjust for tax considerations and charge-offs ⇒ remaining wedge due

to transaction costs etc.

What happens if households had access to cheaper borrowing, at 5%? Welfare gain from baseline IHI: 0.8%

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 34 / 38

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Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Borrowing Cost

We assume an interest rate wedge between borrowing and lending of 6%, based on Davis et al. (2006)

Adjust for tax considerations and charge-offs ⇒ remaining wedge due

to transaction costs etc.

What happens if households had access to cheaper borrowing, at 5%? Welfare gain from baseline IHI: 0.8% Welfare gain from baseline ILL with E(˜ rILL) = rb = 0.05: 3%

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SLIDE 118

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Borrowing Cost

We assume an interest rate wedge between borrowing and lending of 6%, based on Davis et al. (2006)

Adjust for tax considerations and charge-offs ⇒ remaining wedge due

to transaction costs etc.

What happens if households had access to cheaper borrowing, at 5%? Welfare gain from baseline IHI: 0.8% Welfare gain from baseline ILL with E(˜ rILL) = rb = 0.05: 3% Welfare gain from baseline ILL but with E(˜ rILL) = 0.08 > rb: 0.5%

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 34 / 38

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SLIDE 119

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Borrowing Cost

We assume an interest rate wedge between borrowing and lending of 6%, based on Davis et al. (2006)

Adjust for tax considerations and charge-offs ⇒ remaining wedge due

to transaction costs etc.

What happens if households had access to cheaper borrowing, at 5%? Welfare gain from baseline IHI: 0.8% Welfare gain from baseline ILL with E(˜ rILL) = rb = 0.05: 3% Welfare gain from baseline ILL but with E(˜ rILL) = 0.08 > rb: 0.5% Thus, if households had access to borrowing at a cheaper rate than what they would pay on the ILL, result that ILL generates larger gains than IHI may be reversed

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 34 / 38

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SLIDE 120

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Preferences

With higher risk aversion, welfare gains increase

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 35 / 38

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SLIDE 121

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Preferences

With higher risk aversion, welfare gains increase Try γ = 3, β = 0.92 (and equity as earlier, not 50/50)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 35 / 38

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SLIDE 122

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Preferences

With higher risk aversion, welfare gains increase Try γ = 3, β = 0.92 (and equity as earlier, not 50/50) Gain from IHI with ρ = –0.5 and σ = 0.5 is now 0.42% (γ = 2: 0.04%)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 35 / 38

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SLIDE 123

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Preferences

With higher risk aversion, welfare gains increase Try γ = 3, β = 0.92 (and equity as earlier, not 50/50) Gain from IHI with ρ = –0.5 and σ = 0.5 is now 0.42% (γ = 2: 0.04%) Gain from ILL with ρ = +0.5 and σ = 0.5 is now 2.42% (γ = 2: 1.36%)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 35 / 38

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SLIDE 124

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Robustness – Preferences

With higher risk aversion, welfare gains increase Try γ = 3, β = 0.92 (and equity as earlier, not 50/50) Gain from IHI with ρ = –0.5 and σ = 0.5 is now 0.42% (γ = 2: 0.04%) Gain from ILL with ρ = +0.5 and σ = 0.5 is now 2.42% (γ = 2: 1.36%) ⇒ Gains significantly larger with higher risk aversion (as is the welfare cost from life cycle income shocks in the benchmark: 24.5%)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 35 / 38

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SLIDE 125

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 36 / 38

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SLIDE 126

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL vs. IHI Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 36 / 38

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SLIDE 127

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL vs. IHI Correlation with income shocks Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 36 / 38

slide-128
SLIDE 128

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL vs. IHI Correlation with income shocks Volatility Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 36 / 38

slide-129
SLIDE 129

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL vs. IHI Correlation with income shocks Volatility 2 The income-linked assets (in particular ILL) can produce

non-negligible welfare gains

Baseline welfare gains with |ρ| =0.5, σ =0.5: IHI ≈ 0, ILL ≈ 1.4%

(US$400/year)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 36 / 38

slide-130
SLIDE 130

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL vs. IHI Correlation with income shocks Volatility 2 The income-linked assets (in particular ILL) can produce

non-negligible welfare gains

Baseline welfare gains with |ρ| =0.5, σ =0.5: IHI ≈ 0, ILL ≈ 1.4%

(US$400/year)

Attractiveness of alternative investment options matters for relative

gains from ILL vs. IHI

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 36 / 38

slide-131
SLIDE 131

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL vs. IHI Correlation with income shocks Volatility 2 The income-linked assets (in particular ILL) can produce

non-negligible welfare gains

Baseline welfare gains with |ρ| =0.5, σ =0.5: IHI ≈ 0, ILL ≈ 1.4%

(US$400/year)

Attractiveness of alternative investment options matters for relative

gains from ILL vs. IHI

3 But difficult to reduce a large fraction of the welfare costs from labor

income risk with the assets we have considered

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 36 / 38

slide-132
SLIDE 132

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL vs. IHI Correlation with income shocks Volatility 2 The income-linked assets (in particular ILL) can produce

non-negligible welfare gains

Baseline welfare gains with |ρ| =0.5, σ =0.5: IHI ≈ 0, ILL ≈ 1.4%

(US$400/year)

Attractiveness of alternative investment options matters for relative

gains from ILL vs. IHI

3 But difficult to reduce a large fraction of the welfare costs from labor

income risk with the assets we have considered

Unless they were highly correlated with shocks to permanent income...

  • r households had access to cheap borrowing

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 36 / 38

slide-133
SLIDE 133

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

1 Usefulness of income-linked assets depends strongly on how they are

implemented:

ILL vs. IHI Correlation with income shocks Volatility 2 The income-linked assets (in particular ILL) can produce

non-negligible welfare gains

Baseline welfare gains with |ρ| =0.5, σ =0.5: IHI ≈ 0, ILL ≈ 1.4%

(US$400/year)

Attractiveness of alternative investment options matters for relative

gains from ILL vs. IHI

3 But difficult to reduce a large fraction of the welfare costs from labor

income risk with the assets we have considered

Unless they were highly correlated with shocks to permanent income...

  • r households had access to cheap borrowing

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 36 / 38

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SLIDE 134

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

Using a model with realistic portfolio constraints & opportunity costs is key to evaluating new assets

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 37 / 38

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SLIDE 135

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion

Using a model with realistic portfolio constraints & opportunity costs is key to evaluating new assets If instead assumed rb = rl = E(˜ rILA) =0.02, model would predict

IHI and ILL equivalent σ does not matter even with |ρ| =0.5, welfare gain > 4% Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 37 / 38

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SLIDE 136

Introduction Two-Period Example Life-Cycle Model Discussion Robustness Conclusion

Discussion & Conclusion THE END – THANK YOU!

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 38 / 38

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SLIDE 137

Appendix: Welfare Measures

Through large number of simulations of stochastic variables, find ex-ante lifetime expected utility ¯ U Then, compute certainty equivalent consumption ¯ c: constant level of consumption such that lifetime utility equals ¯ U

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 1 / 8

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SLIDE 138

Appendix: Welfare Measures

Through large number of simulations of stochastic variables, find ex-ante lifetime expected utility ¯ U Then, compute certainty equivalent consumption ¯ c: constant level of consumption such that lifetime utility equals ¯ U For benchmark parameters, eliminating income shocks would raise ¯ c by 16.4%

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 1 / 8

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SLIDE 139

Appendix: Welfare Measures

Through large number of simulations of stochastic variables, find ex-ante lifetime expected utility ¯ U Then, compute certainty equivalent consumption ¯ c: constant level of consumption such that lifetime utility equals ¯ U For benchmark parameters, eliminating income shocks would raise ¯ c by 16.4% Alternative measure to assess effect of new assets: coefficient of partial insurance against shocks (Kaplan and Violante, 2008): φu

t = 1 − cov(∆cit, uit)

var(uit)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 1 / 8

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SLIDE 140

Appendix: Welfare Measures

Through large number of simulations of stochastic variables, find ex-ante lifetime expected utility ¯ U Then, compute certainty equivalent consumption ¯ c: constant level of consumption such that lifetime utility equals ¯ U For benchmark parameters, eliminating income shocks would raise ¯ c by 16.4% Alternative measure to assess effect of new assets: coefficient of partial insurance against shocks (Kaplan and Violante, 2008): φu

t = 1 − cov(∆cit, uit)

var(uit) The lower this coefficient, the more an income shock translates into consumption changes. φ = 1: perfect insurance. In benchmark, ¯ φu = 0.08 and ¯ φε = 0.9: easy to insure against transitory shocks, hard to insure against permanent ones.

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 1 / 8

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SLIDE 141

Partial Insurance Coefficients with IHI

ρ = −0.5

Benchmark

ρ = −0.75 ρ = −1

Insurance coefficients (against perm. shocks) during working life age Insurance coefficient 20 25 30 35 40 45 50 55 60 65 0.2 0.4 0.6 0.8 1 Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 2 / 8

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SLIDE 142

Partial Insurance Coefficients with ILL

ρ = 0.5

Benchmark

ρ = 0.75 ↓ ρ = 1 ↓

Insurance coefficients (against perm. shocks) during working life age Insurance coefficient 20 25 30 35 40 45 50 55 60 65 0.2 0.4 0.6 0.8 1 Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 3 / 8

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SLIDE 143

Computational Solution

Closely follow Davis, K¨ ubler, Willen (2006)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 8

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SLIDE 144

Computational Solution

Closely follow Davis, K¨ ubler, Willen (2006) Finite-horizon dynamic program, solved by backward induction

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 8

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SLIDE 145

Computational Solution

Closely follow Davis, K¨ ubler, Willen (2006) Finite-horizon dynamic program, solved by backward induction Get rid of one state by exploiting scale-independence and dividing everything by permanent income

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 8

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SLIDE 146

Computational Solution

Closely follow Davis, K¨ ubler, Willen (2006) Finite-horizon dynamic program, solved by backward induction Get rid of one state by exploiting scale-independence and dividing everything by permanent income Thus, state variables: normalized cash-on-hand (xt) and age (t)

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 8

slide-147
SLIDE 147

Computational Solution

Closely follow Davis, K¨ ubler, Willen (2006) Finite-horizon dynamic program, solved by backward induction Get rid of one state by exploiting scale-independence and dividing everything by permanent income Thus, state variables: normalized cash-on-hand (xt) and age (t) 3 or 4 asset holding decisions, with short-sale constraints on all of them

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 8

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SLIDE 148

Computational Solution

Closely follow Davis, K¨ ubler, Willen (2006) Finite-horizon dynamic program, solved by backward induction Get rid of one state by exploiting scale-independence and dividing everything by permanent income Thus, state variables: normalized cash-on-hand (xt) and age (t) 3 or 4 asset holding decisions, with short-sale constraints on all of them Solve by policy-function iteration, as FOCs necessary and sufficient

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 4 / 8

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SLIDE 149

Computational Solution

Use Garcia-Zangwill (1981) “trick” to transform Kuhn-Tucker conditions into system of nonlinear equations. E.g. for et:

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 5 / 8

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SLIDE 150

Computational Solution

Use Garcia-Zangwill (1981) “trick” to transform Kuhn-Tucker conditions into system of nonlinear equations. E.g. for et: u(

ct

  • xt + bt − lt − et) − βE[(1 + ˜

re)u(ct+1)] − µe,t = 0 et ≥ 0, µe,t ≥ 0, etµe,t = 0

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 5 / 8

slide-151
SLIDE 151

Computational Solution

Use Garcia-Zangwill (1981) “trick” to transform Kuhn-Tucker conditions into system of nonlinear equations. E.g. for et: u(

ct

  • xt + bt − lt − et) − βE[(1 + ˜

re)u(ct+1)] − µe,t = 0 et ≥ 0, µe,t ≥ 0, etµe,t = 0 Define et = (max{0, λe})κ and µe,t = max({0, −λe})κ.

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 5 / 8

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SLIDE 152

Computational Solution

Use Garcia-Zangwill (1981) “trick” to transform Kuhn-Tucker conditions into system of nonlinear equations. E.g. for et: u(

ct

  • xt + bt − lt − et) − βE[(1 + ˜

re)u(ct+1)] − µe,t = 0 et ≥ 0, µe,t ≥ 0, etµe,t = 0 Define et = (max{0, λe})κ and µe,t = max({0, −λe})κ. Then, (max{0, λe})κ ≥ 0, (max{0, −λe})κ ≥ 0, and (max{0, λe})κ · (max{0, −λe})κ = 0

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 5 / 8

slide-153
SLIDE 153

Computational Solution

Use Garcia-Zangwill (1981) “trick” to transform Kuhn-Tucker conditions into system of nonlinear equations. E.g. for et: u(

ct

  • xt + bt − lt − et) − βE[(1 + ˜

re)u(ct+1)] − µe,t = 0 et ≥ 0, µe,t ≥ 0, etµe,t = 0 Define et = (max{0, λe})κ and µe,t = max({0, −λe})κ. Then, (max{0, λe})κ ≥ 0, (max{0, −λe})κ ≥ 0, and (max{0, λe})κ · (max{0, −λe})κ = 0 ⇒ can solve equation that is differentiable of degree κ–1 for λe (and similarly for other assets and multipliers).

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 5 / 8

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SLIDE 154

Computational Solution

Discretization: 2 nodes for income shocks, 3 for equity, 4 for income-linked assets

Results not sensitive to adding more nodes, as long as lowest income

shock “not too small”

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 6 / 8

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SLIDE 155

Computational Solution

Discretization: 2 nodes for income shocks, 3 for equity, 4 for income-linked assets

Results not sensitive to adding more nodes, as long as lowest income

shock “not too small”

Set bounds of grid for cash-on-hand s.th. never move out of bounds in simulations

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 6 / 8

slide-156
SLIDE 156

Computational Solution

Discretization: 2 nodes for income shocks, 3 for equity, 4 for income-linked assets

Results not sensitive to adding more nodes, as long as lowest income

shock “not too small”

Set bounds of grid for cash-on-hand s.th. never move out of bounds in simulations Denser grid at low values of cash-on-hand

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 6 / 8

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SLIDE 157

Computational Solution

Discretization: 2 nodes for income shocks, 3 for equity, 4 for income-linked assets

Results not sensitive to adding more nodes, as long as lowest income

shock “not too small”

Set bounds of grid for cash-on-hand s.th. never move out of bounds in simulations Denser grid at low values of cash-on-hand Solve in Matlab, using dogleg algorithm by H.B. Nielsen

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 6 / 8

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SLIDE 158

Computational Solution

Discretization: 2 nodes for income shocks, 3 for equity, 4 for income-linked assets

Results not sensitive to adding more nodes, as long as lowest income

shock “not too small”

Set bounds of grid for cash-on-hand s.th. never move out of bounds in simulations Denser grid at low values of cash-on-hand Solve in Matlab, using dogleg algorithm by H.B. Nielsen Average consumption-equivalent EE error of order 10−6

Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 6 / 8

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SLIDE 159

Optimal Asset Holdings with IHI

Asset Holdings and Borrowing over the LC (means) Thousands of 1992 USD age Equity Borrowing

No IHI

20 30 40 50 60 70 80

  • 60
  • 40
  • 20

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SLIDE 160

Optimal Asset Holdings with IHI

Asset Holdings and Borrowing over the LC (means) Thousands of 1992 USD age Equity Borrowing IHI

ρ = −0.5

20 30 40 50 60 70 80

  • 60
  • 40
  • 20

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SLIDE 161

Optimal Asset Holdings with IHI

Asset Holdings and Borrowing over the LC (means) Thousands of 1992 USD age

Equity

Borrowing ← IHI

ρ = −0.75

20 30 40 50 60 70 80

  • 60
  • 40
  • 20

20 40 60 Back Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 7 / 8

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SLIDE 162

Optimal Asset Holdings with IHI

Asset Holdings and Borrowing over the LC (means) Thousands of 1992 USD age

Equity →

Borrowing ← IHI

ρ = −1

20 30 40 50 60 70 80

  • 60
  • 40
  • 20

20 40 60 Back Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 7 / 8

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SLIDE 163

Optimal Asset Holdings with ILL

Asset Holdings and Borrowing over the LC (means) Thousands of 1992 USD age Equity Borrowing

No ILL

20 30 40 50 60 70 80

  • 60
  • 40
  • 20

20 40 60 Back Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 8 / 8

slide-164
SLIDE 164

Optimal Asset Holdings with ILL

Asset Holdings and Borrowing over the LC (means) Thousands of 1992 USD age Equity Borrowing ILL

ρ = 0.5

20 30 40 50 60 70 80

  • 60
  • 40
  • 20

20 40 60 Back Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 8 / 8

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SLIDE 165

Optimal Asset Holdings with ILL

Asset Holdings and Borrowing over the LC (means) Thousands of 1992 USD age Equity Borrowing ← ILL

ρ = 0.75

20 30 40 50 60 70 80

  • 60
  • 40
  • 20

20 40 60 Back Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 8 / 8

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SLIDE 166

Optimal Asset Holdings with ILL

Asset Holdings and Borrowing over the LC (means) Thousands of 1992 USD age ← Equity Borrowing ← ILL

ρ = 1

20 30 40 50 60 70 80

  • 60
  • 40
  • 20

20 40 60 Back Andreas Fuster (Harvard) Income-Linked Assets October 16, 2009 8 / 8