Choice theory Michel Bierlaire Transport and Mobility Laboratory - - PowerPoint PPT Presentation

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Choice theory Michel Bierlaire Transport and Mobility Laboratory - - PowerPoint PPT Presentation

Choice theory Michel Bierlaire Transport and Mobility Laboratory School of Architecture, Civil and Environmental Engineering Ecole Polytechnique F ed erale de Lausanne M. Bierlaire (TRANSP-OR ENAC EPFL) Choice theory 1 / 55 Outline


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Choice theory

Michel Bierlaire

Transport and Mobility Laboratory School of Architecture, Civil and Environmental Engineering Ecole Polytechnique F´ ed´ erale de Lausanne

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 1 / 55

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SLIDE 2

Outline

Outline

1

Theoretical foundations Choice theory Decision maker Characteristics Choice set Alternative attributes Decision rule

2

Microeconomic consumer theory Preferences Utility maximization Indirect utility Microeconomic results

3

Discrete goods Utility maximization

4

Simple example

5

Probabilistic choice theory The random utility model

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 2 / 55

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SLIDE 3

Theoretical foundations

Outline

1

Theoretical foundations Choice theory Decision maker Characteristics Choice set Alternative attributes Decision rule

2

Microeconomic consumer theory Preferences Utility maximization Indirect utility Microeconomic results

3

Discrete goods Utility maximization

4

Simple example

5

Probabilistic choice theory The random utility model

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 3 / 55

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Theoretical foundations Choice theory

Choice theory

Choice: outcome of a sequential decision-making process defining the choice problem generating alternatives evaluating alternatives making a choice, executing the choice. Theory of behavior that is descriptive: how people behave and not how they should abstract: not too specific

  • perational: can be used in practice for forecasting
  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 4 / 55

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Theoretical foundations Choice theory

Building the theory

Define

1 who (or what) is the decision maker, 2 what are the characteristics of the decision maker, 3 what are the alternatives available for the choice, 4 what are the attributes of the alternatives, and 5 what is the decision rule that the decision maker uses to make a

choice.

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 5 / 55

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Theoretical foundations Decision maker

Decision maker

Individual a person a group of persons (internal interactions are ignored)

household, family firm government agency

notation: n

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 6 / 55

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Theoretical foundations Characteristics

Characteristics of the decision maker

Disaggregate models Individuals face different choice situations have different tastes Characteristics income sex age level of education household/firm size etc.

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 7 / 55

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Theoretical foundations Choice set

Alternatives

Choice set Non empty finite and countable set of alternatives Universal: C Individual specific: Cn ⊆ C Availability, awareness Example Choice of a transportation model C ={car, bus, metro, walking } If the decision maker has no driver license, and the trip is 12km long Cn = {bus, metro}

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 8 / 55

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Theoretical foundations Choice set

Continuous choice set

Microeconomic demand analysis Commodity bundle q1: quantity of milk q2: quantity of bread q3: quantity of butter Unit price: pi Budget: I q1 q2 q3 p1q1 + p2q2 + p3q3 = I

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 9 / 55

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Theoretical foundations Choice set

Discrete choice set

Discrete choice analysis List of alternatives Brand A Brand B Brand C A B C

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 10 / 55

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Theoretical foundations Alternative attributes

Alternative attributes

Characterize each alternative i for each individual n price travel time frequency comfort color size etc. Nature of the variables Discrete and continuous Generic and specific Measured or perceived

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 11 / 55

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Theoretical foundations Decision rule

Decision rule

Homo economicus Rational and narrowly self-interested economic actor who is optimizing her

  • utcome

Utility Un : Cn − → R : a Un(a) captures the attractiveness of an alternative measure that the decision maker wants to optimize Behavioral assumption the decision maker associates a utility with each alternative the decision maker is a perfect optimizer the alternative with the highest utility is chosen

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 12 / 55

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Microeconomic consumer theory

Outline

1

Theoretical foundations Choice theory Decision maker Characteristics Choice set Alternative attributes Decision rule

2

Microeconomic consumer theory Preferences Utility maximization Indirect utility Microeconomic results

3

Discrete goods Utility maximization

4

Simple example

5

Probabilistic choice theory The random utility model

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 13 / 55

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Microeconomic consumer theory

Microeconomic consumer theory

Continuous choice set Consumption bundle Q =    q1 . . . qL    ; p =    p1 . . . pL    Budget constraint pTQ =

L

  • ℓ=1

pℓqℓ ≤ I. No attributes, just quantities

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 14 / 55

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Microeconomic consumer theory Preferences

Preferences

Operators ≻, ∼, and Qa ≻ Qb: Qa is preferred to Qb, Qa ∼ Qb: indifference between Qa and Qb, Qa Qb: Qa is at least as preferred as Qb. Rationality Completeness: for all bundles a and b, Qa ≻ Qb or Qa ≺ Qb or Qa ∼ Qb. Transitivity: for all bundles a, b and c, if Qa Qb and Qb Qc then Qa Qc. “Continuity”: if Qa is preferred to Qb and Qc is arbitrarily “close” to Qa, then Qc is preferred to Qb.

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 15 / 55

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Microeconomic consumer theory Utility maximization

Utility

Utility function Parametrized function:

  • U =

U(q1, . . . , qL; θ) = U(Q; θ) Consistent with the preference indicator:

  • U(Qa; θ) ≥

U(Qb; θ) is equivalent to Qa Qb. Unique up to an order-preserving transformation

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 16 / 55

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Microeconomic consumer theory Utility maximization

Optimization

Optimization problem max

Q

  • U(Q; θ)

subject to pTQ ≤ I, Q ≥ 0. Demand function Solution of the optimization problem Quantity as a function of prices and budget Q∗ = f (I, p; θ)

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 17 / 55

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Microeconomic consumer theory Utility maximization

Example: Cobb-Douglas

5 10 15 20 q1 5 10 15 20 q2 , q2) = θ0qθ1

1 qθ2 2

5 10 15 20 25

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 18 / 55

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Microeconomic consumer theory Utility maximization

Example

5 10 15 20 5 10 15 20 A B q1 q2

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 19 / 55

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Microeconomic consumer theory Utility maximization

Example

Optimization problem max

q1,q2

  • U(q1, q2; θ0, θ1, θ2) = θ0qθ1

1 qθ2 2

subject to p1q1 + p2q2 = I. Lagrangian of the problem: L(q1, q2, λ) = θ0qθ1

1 qθ2 2 + λ(I − p1q1 − p2q2).

Necessary optimality condition ∇L(q1, q2, λ) = 0

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 20 / 55

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Microeconomic consumer theory Utility maximization

Example

Necessary optimality conditions θ0θ1qθ1−1

1

qθ2

2

− λp1 = (×q1) θ0θ2qθ1

1 qθ2−1 2

− λp2 = (×q2) p1q1 + p2q2 − I = 0. We have θ0θ1qθ1

1 qθ2 2

− λp1q1 = θ0θ2qθ1

1 qθ2 2

− λp2q2 = 0. Adding the two and using the third condition, we obtain λI = θ0qθ1

1 qθ2 2 (θ1 + θ2)

  • r, equivalently,

θ0qθ1

1 qθ2 2 =

λI (θ1 + θ2)

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 21 / 55

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Microeconomic consumer theory Utility maximization

Solution

From the previous derivation θ0qθ1

1 qθ2 2 =

λI (θ1 + θ2) First condition θ0θ1qθ1

1 qθ2 2 = λp1q1.

Solve for q1 q∗

1 =

Iθ1 p1(θ1 + θ2) Similarly, we obtain q∗

2 =

Iθ2 p2(θ1 + θ2)

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 22 / 55

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Microeconomic consumer theory Utility maximization

Optimization problem

q1 q2 q∗

1

q∗

2

I/p1 I/p2 Income constraint

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 23 / 55

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Microeconomic consumer theory Utility maximization

Demand functions

Product 1 q∗

1 = I

p1 θ1 θ1 + θ2 Product 2 q∗

2 = I

p2 θ2 θ1 + θ2 Comments Demand decreases with price Demand increases with budget Demand independent of θ0, which does not affect the ranking Property of Cobb Douglas: the demand for a good is only dependent

  • n its own price and independent of the price of any other good.
  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 24 / 55

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Microeconomic consumer theory Utility maximization

Demand curve (inverse of demand function)

500 1000 1500 2000 2500 3000 3500 4000 5 10 15 20 Price Quantity consumed Good 1, Low income (1000) Good 1, High income (10000) Good 2, Low income (1000) Good 2, High income (10000)

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 25 / 55

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Microeconomic consumer theory Indirect utility

Indirect utility

Substitute the demand function into the utility U(I, p; θ) = θ0 I p1 θ1 θ1 + θ2 θ1 I p2 θ2 θ1 + θ2 θ2 Indirect utility Maximum utility that is achievable for a given set of prices and income In discrete choice...

  • nly the indirect utility is used

therefore, it is simply referred to as “utility” we review some results from microeconomics useful for discrete choice

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 26 / 55

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Microeconomic consumer theory Microeconomic results

Roy’s identity

Derive the demand function from the indirect utility qℓ = −∂U(I, p; θ)/∂pℓ ∂U(I, p; θ)/∂I

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 27 / 55

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Microeconomic consumer theory Microeconomic results

Elasticities

Direct price elasticity Percent change in demand resulting form a 1% change in price E qℓ

pℓ = % change in qℓ

% change in pℓ = ∆qℓ/qℓ ∆pℓ/pℓ = pℓ qℓ ∆qℓ ∆pℓ . Asymptotically E qℓ

pℓ =

pℓ qℓ(I, p; θ) ∂qℓ(I, p; θ) ∂pℓ . Cross price elasticity E qℓ

pm =

pm qℓ(I, p; θ) ∂qℓ(I, p; θ) ∂pm .

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 28 / 55

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Microeconomic consumer theory Microeconomic results

Consumer surplus

Definition Difference between what a consumer is willing to pay for a good and what she actually pays for that good. Calculation Area under the demand curve and above the market price Demand curve Plot of the inverse demand function Price as a function of quantity

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 29 / 55

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Microeconomic consumer theory Microeconomic results

Consumer surplus

Price Quantity Market price Lower price Demand curve Consumer surplus at market price Additional consumer surplus with lower price

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 30 / 55

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Discrete goods

Outline

1

Theoretical foundations Choice theory Decision maker Characteristics Choice set Alternative attributes Decision rule

2

Microeconomic consumer theory Preferences Utility maximization Indirect utility Microeconomic results

3

Discrete goods Utility maximization

4

Simple example

5

Probabilistic choice theory The random utility model

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 31 / 55

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Discrete goods

Microeconomic theory of discrete goods

Expanding the microeconomic framework Continuous goods and discrete goods The consumer selects the quantities of continuous goods: Q = (q1, . . . , qL) chooses an alternative in a discrete choice set i = 1, . . . , j, . . . , J discrete decision vector: (y1, . . . , yJ), yj ∈ {0, 1},

j yj = 1.

Note In theory, one alternative of the discrete choice combines all possible choices made by an individual. In practice, the choice set will be more restricted for tractability

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 32 / 55

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Discrete goods Utility maximization

Utility maximization

Utility

  • U(Q, y, ˜

zTy; θ) Q: quantities of the continuous good y: discrete choice ˜ zT = (˜ z1, . . . , ˜ zi, . . . , ˜ zJ) ∈ RK×J: K attributes of the J alternatives ˜ zTy ∈ RK: attributes of the chosen alternative θ: vector of parameters

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 33 / 55

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Discrete goods Utility maximization

Utility maximization

Optimization problem max

Q,y

  • U(Q, y, ˜

zTy; θ) subject to pTQ + cTy ≤ I

  • j yj = 1

yj ∈ {0, 1}, ∀j. where cT = (c1, . . . , ci, . . . , cJ) contains the cost of each alternative. Solving the problem Mixed integer optimization problem No optimality condition Impossible to derive demand functions directly

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 34 / 55

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Discrete goods Utility maximization

Solving the problem

Step 1: condition on the choice of the discrete good Fix the discrete good, that is select a feasible y. The problem becomes a continuous problem in Q. Conditional demand functions can be derived: qℓ|y = f (I − cTy, p, ˜ zTy; θ),

  • r, equivalently, for each alternative i,

qℓ|i = f (I − ci, p, ˜ zi; θ). I − ci is the income left for the continuous goods, if alternative i is chosen. If I − ci < 0, alternative i is declared unavailable and removed from the choice set.

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 35 / 55

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Discrete goods Utility maximization

Solving the problem

Conditional indirect utility functions Substitute the demand functions into the utility: Ui = U(I − ci, p, ˜ zi; θ) for all i ∈ C. Step 2: Choice of the discrete good max

y

U(I − cTy, p, ˜ zTy; θ) Enumerate all alternatives. Compute the conditional indirect utility function Ui. Select the alternative with the highest Ui. Note: no income constraint anymore.

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 36 / 55

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Discrete goods Utility maximization

Model for individual n

max

y

U(In − cT

n y, pn, ˜

zT

n y; θn)

Simplifications We cannot estimate a set of parameters for each individual n Therefore, population level parameters are interacted with characteristics Sn of the decision-maker Prices of the continuous goods are neglected pn Income is considered as another characteristic and merged into Sn ci is considered as another attribute and merged into ˜ z zn = {˜ zn, cn} max

i

Uin = U(zin, Sn; θ)

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 37 / 55

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Simple example

Outline

1

Theoretical foundations Choice theory Decision maker Characteristics Choice set Alternative attributes Decision rule

2

Microeconomic consumer theory Preferences Utility maximization Indirect utility Microeconomic results

3

Discrete goods Utility maximization

4

Simple example

5

Probabilistic choice theory The random utility model

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 38 / 55

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Simple example

Simple example: mode choice

Attributes Attributes Alternatives Travel time (t) Travel cost (c) Car (1) t1 c1 Bus (2) t2 c2 Utility

  • U =

U(y1, y2), where we impose the restrictions that, for i = 1, 2, yi = 1 if travel alternative i is chosen,

  • therwise;

and that only one alternative is chosen: y1 + y2 = 1.

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 39 / 55

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Simple example

Simple example: mode choice

Choice set y2 y1 (1, 0) (0, 1)

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 40 / 55

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Simple example

Simple example: mode choice

Utility functions U1 = −βtt1 − βcc1, U2 = −βtt2 − βcc2, where βt > 0 and βc > 0 are parameters. Equivalent specification U1 = −(βt/βc)t1 − c1 = −βt1 − c1 U2 = −(βt/βc)t2 − c2 = −βt2 − c2 where β > 0 is a parameter. Choice Alternative 1 is chosen if U1 ≥ U2. Ties are ignored.

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 41 / 55

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Simple example

Simple example: mode choice

Choice Alternative 1 is chosen if −βt1 − c1 ≥ −βt2 − c2

  • r

−β(t1 − t2) ≥ c1 − c2 Alternative 2 is chosen if −βt1 − c1 ≤ −βt2 − c2

  • r

−β(t1 − t2) ≤ c1 − c2 Dominated alternative If c2 > c1 and t2 > t1, U1 > U2 for any β > 0 If c1 > c2 and t1 > t2, U2 > U1 for any β > 0

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 42 / 55

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SLIDE 43

Simple example

Simple example: mode choice

Trade-off Assume c2 > c1 and t1 > t2. Is the traveler willing to pay the extra cost c2 − c1 to save the extra time t1 − t2? Alternative 2 is chosen if −β(t1 − t2) ≤ c1 − c2

  • r

β ≥ c2 − c1 t1 − t2 β is called the willingness to pay or value of time

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 43 / 55

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SLIDE 44

Simple example

Simple example: mode choice

c1 + βt1 = c2 + βt2 t1 − t2 c1 − c2

  • Alt. 1 is dominant
  • Alt. 2 is dominant
  • Alt. 2 is preferred

is preferred β 1

  • Alt. 1 is chosen
  • Alt. 2 is chosen
  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 44 / 55

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SLIDE 45

Probabilistic choice theory

Outline

1

Theoretical foundations Choice theory Decision maker Characteristics Choice set Alternative attributes Decision rule

2

Microeconomic consumer theory Preferences Utility maximization Indirect utility Microeconomic results

3

Discrete goods Utility maximization

4

Simple example

5

Probabilistic choice theory The random utility model

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 45 / 55

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Probabilistic choice theory

Behavioral validity of the utility maximization?

Assumptions Decision-makers are able to process information have perfect discrimination power have transitive preferences are perfect maximizer are always consistent Relax the assumptions Use a probabilistic approach: what is the probability that alternative i is chosen?

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 46 / 55

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Probabilistic choice theory

Introducing probability

Constant utility Human behavior is inherently random Utility is deterministic Consumer does not maximize utility Probability to use inferior alternative is non zero Random utility Decision-maker are rational maximizers Analysts have no access to the utility used by the decision-maker Utility becomes a random variable Niels Bohr Nature is stochastic Albert Einstein God does not throw dice

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 47 / 55

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Probabilistic choice theory The random utility model

Random utility model

Probability model P(i|Cn) = Pr(Uin ≥ Ujn, all j ∈ Cn), Random utility Uin = Vin + εin. Random utility model P(i|Cn) = Pr(Vin + εin ≥ Vjn + εjn, all j ∈ Cn),

  • r

P(i|Cn) = Pr(εjn − εin ≤ Vin − Vjn, all j ∈ Cn).

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 48 / 55

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Probabilistic choice theory The random utility model

Derivation

Joint distributions of εn Assume that εn = (ε1n, . . . , εJnn) is a multivariate random variable with CDF Fεn(ε1, . . . , εJn) and pdf fεn(ε1, . . . , εJn) = ∂JnF ∂ε1 · · · ∂εJn (ε1, . . . , εJn). Derive the model for the first alternative (wlog) Pn(1|Cn) = Pr(V2n + ε2n ≤ V1n + ε1n, . . . , VJn + εJn ≤ V1n + ε1n),

  • r

Pn(1|Cn) = Pr(ε2n − ε1n ≤ V1n − V2n, . . . , εJn − ε1n ≤ V1n − VJn).

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 49 / 55

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Probabilistic choice theory The random utility model

Derivation

Model Pn(1|Cn) = Pr(ε2n − ε1n ≤ V1n − V2n, . . . , εJn − ε1n ≤ V1n − VJn). Change of variables ξ1n = ε1n, ξin = εin − ε1n, i = 2, . . . , Jn, that is        ξ1n ξ2n . . . ξ(Jn−1)n ξJnn        =        1 · · · −1 1 · · · . . . −1 · · · 1 −1 · · · 1               ε1n ε2n . . . ε(Jn−1)n εJnn        .

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 50 / 55

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SLIDE 51

Probabilistic choice theory The random utility model

Derivation

Model in ε Pn(1|Cn) = Pr(ε2n − ε1n ≤ V1n − V2n, . . . , εJn − ε1n ≤ V1n − VJn). Change of variables ξ1n = ε1n, ξin = εin − ε1n, i = 2, . . . , Jn, Model in ξ Pn(1|Cn) = Pr(ξ2n ≤ V1n − V2n, . . . , ξJnn ≤ V1n − VJnn). Note The determinant of the change of variable matrix is 1, so that ε and ξ have the same pdf

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 51 / 55

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SLIDE 52

Probabilistic choice theory The random utility model

Derivation

Pn(1|Cn) = Pr(ξ2n ≤ V1n − V2n, . . . , ξJnn ≤ V1n − VJnn) = Fξ1n,ξ2n,...,ξJn(+∞, V1n − V2n, . . . , V1n − VJnn) = +∞

ξ1=−∞

V1n−V2n

ξ2=−∞

· · · V1n−VJnn

ξJn=−∞

fξ1n,ξ2n,...,ξJn(ξ1, ξ2, . . . , ξJn)dξ, = +∞

ε1=−∞

V1n−V2n+ε1

ε2=−∞

· · · V1n−VJnn+ε1

εJn=−∞

fε1n,ε2n,...,εJn(ε1, ε2, . . . , εJn)dε,

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 52 / 55

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SLIDE 53

Probabilistic choice theory The random utility model

Derivation

Pn(1|Cn) = +∞

ε1=−∞

V1n−V2n+ε1

ε2=−∞

· · · V1n−VJnn+ε1

εJn=−∞

fε1n,ε2n,...,εJn(ε1, ε2, . . . , εJn)d Pn(1|Cn) = +∞

ε1=−∞

∂Fε1n,ε2n,...,εJn ∂ε1 (ε1, V1n−V2n+ε1, . . . , V1n−VJnn+ε1)dε1. The random utility model: Pn(i|Cn) = +∞

ε=−∞

∂Fε1n,ε2n,...,εJn ∂εi (. . . , Vin − V(i−1)n + ε, ε, Vin − V(i+1)n + ε, . . .)dε

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 53 / 55

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Probabilistic choice theory The random utility model

Random utility model

The general formulation is complex. We will derive specific models based on simple assumptions. We will then relax some of these assumptions to propose more advanced models.

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 54 / 55

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SLIDE 55

Probabilistic choice theory The random utility model

Outline

1

Theoretical foundations Choice theory Decision maker Characteristics Choice set Alternative attributes Decision rule

2

Microeconomic consumer theory Preferences Utility maximization Indirect utility Microeconomic results

3

Discrete goods Utility maximization

4

Simple example

5

Probabilistic choice theory The random utility model

  • M. Bierlaire (TRANSP-OR ENAC EPFL)

Choice theory 55 / 55