Bayesian Model-Agnostic Meta-Learning Taesup Kim* (presenter), - - PowerPoint PPT Presentation

bayesian model agnostic meta learning
SMART_READER_LITE
LIVE PREVIEW

Bayesian Model-Agnostic Meta-Learning Taesup Kim* (presenter), - - PowerPoint PPT Presentation

Bayesian Model-Agnostic Meta-Learning Taesup Kim* (presenter), Jaesik Yoon* Ousmane Dia, Sungwoong Kim, Yoshua Bengio, Sungjin Ahn Model-Agnostic Meta-learning (MAML) gradient-based meta-learning framework meta-update task adaptation


slide-1
SLIDE 1

Bayesian Model-Agnostic Meta-Learning

Taesup Kim* (presenter), Jaesik Yoon* Ousmane Dia, Sungwoong Kim, Yoshua Bengio, Sungjin Ahn

slide-2
SLIDE 2

Model-Agnostic Meta-learning (MAML)

“gradient-based meta-learning framework”

meta-update task adaptation

initial parameters

slide-3
SLIDE 3

Model-Agnostic Meta-learning (MAML)

For each task in a batch: Task adaptation Task Model Meta-update Initial Model

slide-4
SLIDE 4

Gradient-Based Meta-Learning + “Bayesian”

Robust to over!tting Safe/e'cient exploration Active learning

Uncertainty

slide-5
SLIDE 5

Lightweight Laplace Approximation for Meta-Adaptation (LLAMA)

MAML LLAMA

meta-update task adaptation

slide-6
SLIDE 6

Gaussian Approximation

Lightweight Laplace Approximation for Meta-Adaptation (LLAMA)

meta-update task adaptation

slide-7
SLIDE 7

Lightweight Laplace Approximation for Meta-Adaptation (LLAMA)

meta-update task adaptation

Gaussian Approximation No uncertainty for initial model

slide-8
SLIDE 8

Lightweight Laplace Approximation for Meta-Adaptation (LLAMA)

meta-update task adaptation

Gaussian Approximation No uncertainty for initial model

slide-9
SLIDE 9

MAML LLAMA BMAML

Bayesian Model-Agnostic Meta-Learning (BMAML)

point estimate Gaussian approx. complex multimodal

meta-update task adaptation

slide-10
SLIDE 10

meta-update task adaptation

BMAML complex multimodal

Meta-update Initial Model Bayesian meta-update Initial distribution For each task in a batch: Task adaptation Task Model Bayesian fast adaptation Task Distribution

Bayesian Model-Agnostic Meta-Learning (BMAML)

slide-11
SLIDE 11

Model-Agnostic Meta-Learning (MAML) Stein Variational Gradient Descent (SVGD)

“gradient-based meta-learning framework” “particle-based posterior approximation”

+

Bayesian Fast Adaptation (BFA)

θ1 θ2 θ3 θ4

slide-12
SLIDE 12

“particle-based posterior approximation”

Stein Variational Gradient Descent (SVGD)

“backprop to initial model through deterministic SVGD particles”

∇θilog p(θi) k(θi, θj)

slide-13
SLIDE 13

Bayesian Fast Adaptation (BFA)

Meta-update Meta-loss Initial distribution

slide-14
SLIDE 14

Bayesian Fast Adaptation (BFA)

Task adaptation Task 2 
 posterior Task 1 
 posterior Task 3 
 posterior Initial distribution

slide-15
SLIDE 15

Bayesian Meta-Update with Chaser Loss

“extend uncertainty-awareness to meta-update”

Chaser Leader Initial

“Distance = Chaser Loss”

current task posterior target task posterior

slide-16
SLIDE 16

Bayesian Meta-Update with Chaser Loss

Chaser Leader Initial

“Distance = Chaser Loss”

current task posterior target task posterior

slide-17
SLIDE 17

Bayesian Meta-Update with Chaser Loss

Chaser Initial

2 Tt do Compute chaser Θn

τ (Θ0) = SVGDn(Θ0; Dtrn τ , α)

Compute leader

n+s

SVGD

n

D

For each task,

  • Compute CHASER PARTICLES
slide-18
SLIDE 18

Bayesian Meta-Update with Chaser Loss

Chaser Leader

Compute chaser

τ

SVGDn

0 Dτ

Compute leader Θn+s

τ

(Θ0) = SVGDs(Θn

τ (Θ0); Dtrn τ [ Dval τ , α)

Initial

For each task,

  • Compute CHASER PARTICLES
  • Compute LEADER PARTICLES
slide-19
SLIDE 19

For each task,

  • Compute CHASER PARTICLES
  • Compute LEADER PARTICLES
  • Compute CHASER LOSS

Bayesian Meta-Update with Chaser Loss

Chaser Leader Initial

“Distance = Chaser Loss”

LBMAML(Θ0) = X

τ∈Tt

ds(Θn

τ k Θn+s τ

) = X

τ∈Tt M

X

m=1

kθn,m

τ

θn+s,m

τ

k2

2.

slide-20
SLIDE 20

Regression Image Classification Active Learning

Experiments

  • prevent over!tting with better performance
  • evaluate e ectiveness of measured uncertainty
slide-21
SLIDE 21

Experiments

Reinforcement Learning

  • better policy exploration
slide-22
SLIDE 22

See you at Poster “AB #15” (room 210 & 230)