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Causal Models under Variable Transformations Challenges for Causally - - PowerPoint PPT Presentation

c o p e n h a g e n c a u s a l i t y l a b university of copenhagen Causal Models under Variable Transformations Challenges for Causally Consistent Representation Learning Sebastian Weichwald sweichwald.de @sweichwald ETH Guest Lecture


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c o p e n h a g e n c a u s a l i t y l a b

university of copenhagen

Causal Models under Variable Transformations

Challenges for Causally Consistent Representation Learning Sebastian Weichwald

sweichwald.de

@sweichwald

ETH Guest Lecture 2020-10-06

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u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 2 Weingärtner, et al (2010). Relationship between cholesterol synthesis and intestinal absorption isassociated with cardiovascular risk. Atherosclerosis.

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u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 3 Weingärtner, et al (2010). Relationship between cholesterol synthesis and intestinal absorption isassociated with cardiovascular risk. Atherosclerosis.

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u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Variable Transformations may break Causal Reasoning diet LDL HDL heart disease − +

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 4 Rubenstein*, Weichwald*, et al (2017). Causal Consistency of Structural Equation Models. Uncertainty in Artificial Intelligence.

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u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Variable Transformations may break Causal Reasoning diet total chol. heart disease − + diet LDL HDL heart disease − +

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 4 Rubenstein*, Weichwald*, et al (2017). Causal Consistency of Structural Equation Models. Uncertainty in Artificial Intelligence.

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Variable Transformations may break Causal Reasoning diet total chol. heart disease − +

diet LDL HDL heart disease − +

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 4 Rubenstein*, Weichwald*, et al (2017). Causal Consistency of Structural Equation Models. Uncertainty in Artificial Intelligence.

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u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Observables may not be (meaningful) Causal Entities

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 5

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u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Observables may not be (meaningful) Causal Entities

C1 C2 Ci

causal entities

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 5

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Observables may not be (meaningful) Causal Entities

C1 C2 Ci

causal entities linear mixing

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 5

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Observables may not be (meaningful) Causal Entities

C1 C2 Ci

F1 F2 F3 causal entities linear mixing

  • bserved linear mixture

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 5

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Observables may not be (meaningful) Causal Entities

C1 C2 Ci

F1 F2 F3 causal entities taking a photo

  • bserved rgb pixel values

C4 C5

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 5

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Sebastian Weichwald — Causal Models under Variable Transformations — Slide 6 Runge et al. (2019). Inferring causation from time series in Earth system sciences. Nature Communications.

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Variable Transformations may link Causal Reasoning at Different Scales fine-grained coarse-grained

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 7

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MX MY

X1 X2 X3 X4 X5 X6 휏1(X) 휏2(X) 휏3(X) 휏 ?

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Causal Consistency of Structural Equation Models auai.org/uai2017/proceedings/papers/11.pdf Paul Rubenstein, S Weichwald, S Bongers, JM Mooij, D Janzing, M Grosse-Wentrup, B Schölkopf

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 8 Rubenstein*, Weichwald*, et al (2017). Causal Consistency of Structural Equation Models. Uncertainty in Artificial Intelligence.

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Causal Models as Posets of Distributions

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“Normal” Probabilistic Model: MX : 휃 ↦→ P휃

P휃

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 9

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“Normal” Probabilistic Model: MX : 휃 ↦→ P휃

P휃

Causal Model: MX : 휃 ↦→ {Pdo(i)

: i ∈ I

X}

I

X is set of interventions. P∅

Pdo(i1)

Pdo(i2)

Pdo(i3)

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 9

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Causal Models

P∅

X

Pdo(A=0)

X

Pdo(A=0,C=0)

X

Pdo(C=0)

X

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 10

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Causal Models

P∅

X

Pdo(A=0)

X

Pdo(A=0,C=0)

X

Pdo(C=0)

X

I

X has partial ordering structure

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 10

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Causal Models

P∅

X

Pdo(A=0)

X

Pdo(A=0,C=0)

X

Pdo(C=0)

X

I

X has partial ordering structure

MX implies the poset of distributions PX :=

  • Pdo(i)

X

: i ∈ I

X

  • , ≤X
  • Sebastian Weichwald — Causal Models under Variable Transformations — Slide 10
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Structural Causal Models MX = (SX, I

X, PEX)

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 11

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Structural Causal Models MX = (SX, I

X, PEX)

  • SX =

       X1 = E1 X2 = X1 + E2

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 11

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Structural Causal Models MX = (SX, I

X, PEX)

  • SX =

       X1 = E1 X2 = X1 + E2

  • I

X = {∅, do(X1 = 5), do(X2 = 3)}

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 11

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Structural Causal Models MX = (SX, I

X, PEX)

  • SX =

       X1 = E1 X2 = X1 + E2

  • I

X = {∅, do(X1 = 5), do(X2 = 3)}

  • E ∼ N (0, I)

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 11

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Structural Causal Models MX = (SX, I

X, PEX)

  • SX =

       X1 = E1 X2 = X1 + E2

  • I

X = {∅, do(X1 = 5), do(X2 = 3)}

  • E ∼ N (0, I)
  • bservational

P∅

X1 ∼ N (0, 1)

P∅

X2 ∼ N (0, 2)

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 11

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Structural Causal Models MX = (SX, I

X, PEX)

  • SX =

       X1 = E1 X2 = X1 + E2

  • I

X = {∅, do(X1 = 5), do(X2 = 3)}

  • E ∼ N (0, I)
  • bservational

P∅

X1 ∼ N (0, 1)

P∅

X2 ∼ N (0, 2)

intervention on X1 Pdo(X1=5)

X1

≡ 5 Pdo(X1=5)

X2

∼ N (5, 1)

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 11

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Structural Causal Models MX = (SX, I

X, PEX)

  • SX =

       X1 = E1 X2 = X1 + E2

  • I

X = {∅, do(X1 = 5), do(X2 = 3)}

  • E ∼ N (0, I)
  • bservational

P∅

X1 ∼ N (0, 1)

P∅

X2 ∼ N (0, 2)

intervention on X1 Pdo(X1=5)

X1

≡ 5 Pdo(X1=5)

X2

∼ N (5, 1) intervention on X2 Pdo(X2=3)

X1

∼ N (0, 1) Pdo(X2=3)

X2

≡ 3

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 11

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  • bservations

causal model causal discovery? P∅

X

Pdo(i1)

X

  • Pdo(i)

X

: i ∈ I

sub I X

  • P∅

X

Pdo(i1)

X

Pdo(i3)

X

Pdo(i2)

X

  • Pdo(i)

X

: i ∈ I

X I sub

  • Sebastian Weichwald — Causal Models under Variable Transformations — Slide 12
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A B C B A C h A B C P∅

X

Pdo(i1)

X

Pdo(i3)

X

Pdo(i2)

X

P∅

X

Pdo(i1)

X

Pdo(i3)

X

Pdo(i2)

X

P∅

X

Pdo(i1)

X

Pdo(i3)

X

Pdo(i2)

X

A = 1/

2B − 1/ 2C+

  • 3/

2NA

B = √ 3NB C = 1/

3B

+

  • 2/

3NC

A = √ 2NA B = 1/

2A + C+

  • 3/

2NB

C = NC A = h +NA B = h + C+NB C = NC

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 13

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A B C B A C h A B C P∅

X

Pdo(i1)

X

Pdo(i3)

X

Pdo(i2)

X

P∅

X

Pdo(i1)

X

Pdo(i3)

X

Pdo(i2)

X

P∅

X

Pdo(i1)

X

Pdo(i3)

X

Pdo(i2)

X

A = 1/

2B − 1/ 2C+

  • 3/

2NA

B = √ 3NB C = 1/

3B

+

  • 2/

3NC

A = √ 2NA B = 1/

2A + C+

  • 3/

2NB

C = NC A = h +NA B = h + C+NB C = NC

3 models inducing the same observational yet different interventional distributions

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 13

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A B C B A C h A B C P∅

X

Pdo(i1)

X

Pdo(i3)

X

Pdo(i2)

X

P∅

X

Pdo(i1)

X

Pdo(i3)

X

Pdo(i2)

X

P∅

X

Pdo(i1)

X

Pdo(i3)

X

Pdo(i2)

X

A = 1/

2B − 1/ 2C+

  • 3/

2NA

B = √ 3NB C = 1/

3B

+

  • 2/

3NC

A = √ 2NA B = 1/

2A + C+

  • 3/

2NB

C = NC A = h +NA B = h + C+NB C = NC

3 models inducing the same observational yet different interventional distributions fiting observational data well is not enough

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 13

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MX MY

X1 X2 X3 X4 X5 X6 휏1(X) 휏2(X) 휏3(X) 휏 ?

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Sebastian Weichwald — Causal Models under Variable Transformations — Slide 14 Pearl (2009). Causality: Models, Reasoning, and Inference.

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The Three Layer Causal Hierarchy

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 15 Pearl (2018). Theoretical Impediments to Machine Learning – With Seven Sparks from the Causal Revolution. WSDM 2018.

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The Three Layer Causal Hierarchy presupposes that X and Y are the right variables

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 15 Pearl (2018). Theoretical Impediments to Machine Learning – With Seven Sparks from the Causal Revolution. WSDM 2018.

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Needed: Understanding of SCMs under Variable Transformations

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 16

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Needed: Understanding of SCMs under Variable Transformations Suppose we are given MX and a transformation 휏 : X → Y

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 16

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Needed: Understanding of SCMs under Variable Transformations Suppose we are given MX and a transformation 휏 : X → Y X ∼ PX an r.v. in X =⇒ 휏(X) ∼ P휏(X) is an r.v. in Y

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 16

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Needed: Understanding of SCMs under Variable Transformations Suppose we are given MX and a transformation 휏 : X → Y X ∼ PX an r.v. in X =⇒ 휏(X) ∼ P휏(X) is an r.v. in Y 휏 : PX → P휏(X) =

  • Pi

휏(X)

: i ∈ I

X

  • , ≤X
  • Sebastian Weichwald — Causal Models under Variable Transformations — Slide 16
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u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Needed: Understanding of SCMs under Variable Transformations Suppose we are given MX and a transformation 휏 : X → Y X ∼ PX an r.v. in X =⇒ 휏(X) ∼ P휏(X) is an r.v. in Y 휏 : PX → P휏(X) =

  • Pi

휏(X)

: i ∈ I

X

  • , ≤X

PX P휏(X)

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 16

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Needed: Understanding of SCMs under Variable Transformations Suppose we are given MX and a transformation 휏 : X → Y X ∼ PX an r.v. in X =⇒ 휏(X) ∼ P휏(X) is an r.v. in Y 휏 : PX → P휏(X) =

  • Pi

휏(X)

: i ∈ I

X

  • , ≤X

PX P휏(X)

Does there exist an SCM MY with PY = P휏(X)? If so, then MY will agree with our observations of MX via 휏.

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 16

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What can go wrong? MX : X1 X2 X3 SX =          X1 = E1 X2 = E2 X3 = X1 + X2 + E3 E2 = 1; E1, E3 arbitrary I

X =

         do(∅) do(X1 = 0) do(X1 = 0, X2 = 0)

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 SX =          X1 = E1 X2 = E2 X3 = X1 + X2 + E3 E2 = 1; E1, E3 arbitrary I

X =

         do(∅) do(X1 = 0) do(X1 = 0, X2 = 0) MY : Y1 = X1 + X2 Y2 = X3

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 SX =          X1 = E1 X2 = E2 X3 = X1 + X2 + E3 E2 = 1; E1, E3 arbitrary I

X =

         do(∅) do(X1 = 0) do(X1 = 0, X2 = 0) MY : Y1 = X1 + X2 Y2 = X3 SY =

  • Y1 = E1 + E2

Y2 = Y1 + E3

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 SX =          X1 = E1 X2 = E2 X3 = X1 + X2 + E3 E2 = 1; E1, E3 arbitrary I

X =

         do(∅) do(X1 = 0) do(X1 = 0, X2 = 0) MY : Y1 = X1 + X2 Y2 = X3 SY =

  • Y1 = E1 + E2

Y2 = Y1 + E3 E1, E2, E3 as before

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 SX =          X1 = E1 X2 = E2 X3 = X1 + X2 + E3 E2 = 1; E1, E3 arbitrary I

X =

         do(∅) do(X1 = 0) do(X1 = 0, X2 = 0) MY : Y1 = X1 + X2 Y2 = X3 SY =

  • Y1 = E1 + E2

Y2 = Y1 + E3 E1, E2, E3 as before I

Y =

        

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 SX =          X1 = E1 X2 = E2 X3 = X1 + X2 + E3 E2 = 1; E1, E3 arbitrary I

X =

         do(∅) do(X1 = 0) do(X1 = 0, X2 = 0) MY : Y1 = X1 + X2 Y2 = X3 SY =

  • Y1 = E1 + E2

Y2 = Y1 + E3 E1, E2, E3 as before I

Y =

         do(∅)

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 SX =          X1 = E1 X2 = E2 X3 = X1 + X2 + E3 E2 = 1; E1, E3 arbitrary I

X =

         do(∅) do(X1 = 0) do(X1 = 0, X2 = 0) MY : Y1 = X1 + X2 Y2 = X3 SY =

  • Y1 = E1 + E2

Y2 = Y1 + E3 E1, E2, E3 as before I

Y =

         do(∅) do(Y1 = 1)

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 SX =          X1 = E1 X2 = E2 X3 = X1 + X2 + E3 E2 = 1; E1, E3 arbitrary I

X =

         do(∅) do(X1 = 0) do(X1 = 0, X2 = 0) MY : Y1 = X1 + X2 Y2 = X3 SY =

  • Y1 = E1 + E2

Y2 = Y1 + E3 E1, E2, E3 as before I

Y =

         do(∅) do(Y1 = 1) do(Y1 = 0)

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 MY : Y1 = X1 + X2 Y2 = X3

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 MY : Y1 = X1 + X2 Y2 = X3 PX Pdo(X1=0)

X

Pdo(X1=0,X2=0)

X

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 MY : Y1 = X1 + X2 Y2 = X3 PX Pdo(X1=0)

X

Pdo(X1=0,X2=0)

X

PY 휏

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 MY : Y1 = X1 + X2 Y2 = X3 PX Pdo(X1=0)

X

Pdo(X1=0,X2=0)

X

PY 휏 Pdo(Y1=1)

Y

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 MY : Y1 = X1 + X2 Y2 = X3 PX Pdo(X1=0)

X

Pdo(X1=0,X2=0)

X

PY 휏 Pdo(Y1=1)

Y

휏 Pdo(Y1=0)

Y

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 MY : Y1 = X1 + X2 Y2 = X3 PX Pdo(X1=0)

X

Pdo(X1=0,X2=0)

X

PY 휏 Pdo(Y1=1)

Y

휏 Pdo(Y1=0)

Y

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 MY : Y1 = X1 + X2 Y2 = X3 PX Pdo(X1=0)

X

Pdo(X1=0,X2=0)

X

PY 휏 Pdo(Y1=1)

Y

휏 Pdo(Y1=0)

Y

×

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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What can go wrong? MX : X1 X2 X3 MY : Y1 = X1 + X2 Y2 = X3 PX Pdo(X1=0)

X

Pdo(X1=0,X2=0)

X

PY 휏 Pdo(Y1=1)

Y

휏 Pdo(Y1=0)

Y

×

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 17

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Exact Transformations ensure Causally Consistent SCMs

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 18

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Exact Transformations ensure Causally Consistent SCMs Let MX = SX, I

X, PEX

be an SCM over variables X = (Xi : i ∈ IX) with

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 18

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Exact Transformations ensure Causally Consistent SCMs Let MX = SX, I

X, PEX

be an SCM over variables X = (Xi : i ∈ IX) with

1 structural equations SX;

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 18

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Exact Transformations ensure Causally Consistent SCMs Let MX = SX, I

X, PEX

be an SCM over variables X = (Xi : i ∈ IX) with

1 structural equations SX; 2 restricted partially ordered set (I

X, ≤X) of interventions;

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 18

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Exact Transformations ensure Causally Consistent SCMs Let MX = SX, I

X, PEX

be an SCM over variables X = (Xi : i ∈ IX) with

1 structural equations SX; 2 restricted partially ordered set (I

X, ≤X) of interventions;

3 exogenous variables distributed according to PEX.

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 18

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Exact Transformations ensure Causally Consistent SCMs Let MX = SX, I

X, PEX

be an SCM over variables X = (Xi : i ∈ IX) with

1 structural equations SX; 2 restricted partially ordered set (I

X, ≤X) of interventions;

3 exogenous variables distributed according to PEX.

Let MY = SY, I

Y, PEY

be another SCM and 휏 : X → Y.

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 18

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Exact Transformations ensure Causally Consistent SCMs Let MX = SX, I

X, PEX

be an SCM over variables X = (Xi : i ∈ IX) with

1 structural equations SX; 2 restricted partially ordered set (I

X, ≤X) of interventions;

3 exogenous variables distributed according to PEX.

Let MY = SY, I

Y, PEY

be another SCM and 휏 : X → Y. MY is an exact 휏-transformation of MX if

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 18

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Exact Transformations ensure Causally Consistent SCMs Let MX = SX, I

X, PEX

be an SCM over variables X = (Xi : i ∈ IX) with

1 structural equations SX; 2 restricted partially ordered set (I

X, ≤X) of interventions;

3 exogenous variables distributed according to PEX.

Let MY = SY, I

Y, PEY

be another SCM and 휏 : X → Y. MY is an exact 휏-transformation of MX if Pi

휏(X) = Pdo(휔(i)) Y

∀i ∈ I

X

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 18

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Exact Transformations ensure Causally Consistent SCMs Let MX = SX, I

X, PEX

be an SCM over variables X = (Xi : i ∈ IX) with

1 structural equations SX; 2 restricted partially ordered set (I

X, ≤X) of interventions;

3 exogenous variables distributed according to PEX.

Let MY = SY, I

Y, PEY

be another SCM and 휏 : X → Y. MY is an exact 휏-transformation of MX if Pi

휏(X) = Pdo(휔(i)) Y

∀i ∈ I

X

for a surjective order-preserving map 휔 : I

X → I Y.

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 18

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Exact Transformations ensure Causally Consistent SCMs Let MX = SX, I

X, PEX

be an SCM over variables X = (Xi : i ∈ IX) with

1 structural equations SX; 2 restricted partially ordered set (I

X, ≤X) of interventions;

3 exogenous variables distributed according to PEX.

Let MY = SY, I

Y, PEY

be another SCM and 휏 : X → Y. MY is an exact 휏-transformation of MX if Pi

휏(X) = Pdo(휔(i)) Y

∀i ∈ I

X

for a surjective order-preserving map 휔 : I

X → I Y.

=⇒ MX and MY are causally consistent

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 18

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Causal Consistency PX Pdo(i)

X

Pdo(j)

X

PY Pdo(휔(i))

Y

Pdo(휔(j))

Y

do(i) do(j) do(휔(i)) do(휔(j)) 휏 휏 휏

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 19

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Elementary Properties of Exact Transformations

Lemma

The identity mapping is an exact transformation.

MX MX id

Lemma

Exact transformations are transitively closed.

MX MY MZ 휏1 휏2 휏2 ◦ 휏1

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 20

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Few Transformations yield Causally Consistent Representations

  • Marginalisation of variables

X1 X2 X3 MX

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 21

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Few Transformations yield Causally Consistent Representations

  • Marginalisation of variables

X1 X2 X3 MX subsystem MY

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 21

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Few Transformations yield Causally Consistent Representations

  • Marginalisation of variables
  • Micro- to macro-level and aggregate features

MX:

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 21

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Few Transformations yield Causally Consistent Representations

  • Marginalisation of variables
  • Micro- to macro-level and aggregate features

MX:

  • W
  • Z

MY:

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 21

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Few Transformations yield Causally Consistent Representations

  • Marginalisation of variables
  • Micro- to macro-level and aggregate features
  • Stationary behaviour of dynamical processes

. . . . . . . . . . . . . . . . . . . . . . . . do(i) dynamic MX X1

t

X2

t

X1

t

X2

t

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 21

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Few Transformations yield Causally Consistent Representations

  • Marginalisation of variables
  • Micro- to macro-level and aggregate features
  • Stationary behaviour of dynamical processes

. . . . . . . . . . . . . . . . . . . . . . . . do(i) dynamic MX stationary MY Y1 Y2 Y1 Y2 do(휔(i))

휏 휏

X1

t

X2

t

X1

t

X2

t

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 21

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Causal Models under Variable Transformations Challenges for Causally Consistent Representation Learning Lab Causality Copenhagen @sweichwald

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 22

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Causal Models under Variable Transformations Challenges for Causally Consistent Representation Learning

  • Variable Transformations may break Causal Reasoning

Lab Causality Copenhagen @sweichwald

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 22

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u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Causal Models under Variable Transformations Challenges for Causally Consistent Representation Learning

  • Variable Transformations may break Causal Reasoning
  • Observables may not be (meaningful) Causal Entities

Lab Causality Copenhagen @sweichwald

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 22

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u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Causal Models under Variable Transformations Challenges for Causally Consistent Representation Learning

  • Variable Transformations may break Causal Reasoning
  • Observables may not be (meaningful) Causal Entities
  • Variable Transformations may link Causal Reasoning at Different Scales

Lab Causality Copenhagen @sweichwald

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 22

slide-83
SLIDE 83

u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Causal Models under Variable Transformations Challenges for Causally Consistent Representation Learning

  • Variable Transformations may break Causal Reasoning
  • Observables may not be (meaningful) Causal Entities
  • Variable Transformations may link Causal Reasoning at Different Scales
  • Needed: Understanding of SCMs under Variable Transformations

Lab Causality Copenhagen @sweichwald

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 22

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SLIDE 84

u n i v e r s i t y o f c o p e n h a g e n c o p e n h a g e n c a u s a l i t y l a b

Causal Models under Variable Transformations Challenges for Causally Consistent Representation Learning

  • Variable Transformations may break Causal Reasoning
  • Observables may not be (meaningful) Causal Entities
  • Variable Transformations may link Causal Reasoning at Different Scales
  • Needed: Understanding of SCMs under Variable Transformations
  • Few Transformations yield Causally Consistent Representations

Lab Causality Copenhagen @sweichwald

Sebastian Weichwald — Causal Models under Variable Transformations — Slide 22