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Turning a Blind Eye: Explicit Removal of Biases and Variation from - - PowerPoint PPT Presentation

Turning a Blind Eye: Explicit Removal of Biases and Variation from Deep Neural Network Embeddings Mohsan Alvi, Andrew Zisserman, and Christoffer Nellker Bias Estimation in Face Analytics ECCV 2018 Workshop, 14/09/2018 Introduction


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Turning a Blind Eye:

Explicit Removal of Biases and Variation from Deep Neural Network Embeddings

Mohsan Alvi, Andrew Zisserman, and Christoffer Nellåker Bias Estimation in Face Analytics ECCV 2018 Workshop, 14/09/2018

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Introduction

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Convolutional Neural Networks are the state-of-the-art in image classification

Rely on “good” training data Not clear what the network has learned Networks can cheat by learning spurious variations Lack of comprehensively annotated data

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Contents

  • Removing a bias from a network
  • Removing multiple spurious variations from a network
  • LAOFIW – Labeled Ancestral Faces in the Wild

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Spurious Variations vs Biases

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Spurious Variations Biases “Side information”

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Gender Classification from Celebrity Faces

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IMDB Faces Dataset [1]

  • Dataset consists of celebrity faces from International Movie DataBase
  • Contains Age, Gender, Identity Labels
  • Created two subsets of the dataset
  • Age
  • Gender
  • Cleaned labels

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[1] Rothe, Timofte, Van Gool. (2015)

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Biased Datasets

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Extremely Biased Datasets

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Training data

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Test data

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Extremely Biased Datasets

Only young women, only old men

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Training on Extremely Biased Data

Evaluated on a gender/age balanced test dataset

Gender classification accuracy: 70%

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Turning a Blind Eye

  • Primary task is the attribute of interest
  • Gender Classification
  • Secondary task denotes bias to be unlearned
  • Age Classification
  • Objective:

learn feature representation that is informative for primary task, and uninformative for secondary task

  • Repurpose work in field of domain adaptation [2]

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[2] Tzeng, Hoffman, Darrell, and Saenko. (2015)

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Methods (1/3)

Based on VGG-M Network [2]

[2] Chatfield, Simonyan, Vedaldi, and Zisserman. (2014)

Minimize:

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Methods (2/3)

Primary Loss

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Minimize:

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Methods (3/3)

Cross-entropy between classifier output and uniform distribution

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Minimize: Confusion Loss Secondary Loss

Secondary Classification Secondary Confusion

Act in opposition to each other Alternate:

Primary Classification & Secondary Confusion Secondary Classification Primary Classification Secondary Confusion

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Results – Removing a bias

Baseline Gender classification accuracy: 70% Age-Blind Gender classification accuracy: 86%

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Removing multiple spurious variations (1/2)

Problem 1: Multiple biases may be present in dataset

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Age Gender Pose Expression Ancestry

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Removing multiple spurious variations (2/2)

  • Problem 2: no single dataset contains labels for all biases
  • Each labeled for a single purpose
  • Leverage information from multiple datasets

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Dataset 3: Ancestry Dataset 1: Gender Dataset 4: Pose Dataset 2: Age

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14,000 images in four classes:

  • Sub-Saharan Africa
  • Western Europe
  • East Asia
  • Indian subcontinent

Labeled Ancestral Origin Faces in the Wild LAOFIW

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Methods - Removing multiple spurious variations

For M secondary tasks:

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Removing multiple spurious variations experiments

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Ancestry Gender* Pose Age Gender Ancestry Pose Age

Experiment (1) Experiment (2) * Not extremely biased

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Results - Removing multiple spurious variations (1/2)

Primary task: Gender Secondary tasks: Age, Ancestry, Pose

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Results - Removing multiple spurious variations (2/2)

Primary task: Ancestry Secondary tasks: Age, Gender, Pose

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Conclusions

  • Can improve generalizability of models train on biased datasets
  • Can remove multiple spurious variations from feature representation
  • f network
  • LAOFIW – ancestral origin dataset

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Questions?

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