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Dont Judge an Object by Its Context: Learning to Overcome Contextual Bias

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 نشر من قبل Krishna Kumar Singh
 تاريخ النشر 2020
  مجال البحث الهندسة المعلوماتية
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Existing models often leverage co-occurrences between objects and their context to improve recognition accuracy. However, strongly relying on context risks a models generalizability, especially when typical co-occurrence patterns are absent. This work focuses on addressing such contextual biases to improve the robustness of the learnt feature representations. Our goal is to accurately recognize a category in the absence of its context, without compromising on performance when it co-occurs with context. Our key idea is to decorrelate feature representations of a category from its co-occurring context. We achieve this by learning a feature subspace that explicitly represents categories occurring in the absence of context along side a joint feature subspace that represents both categories and context. Our very simple yet effective method is extensible to two multi-label tasks -- object and attribute classification. On 4 challenging datasets, we demonstrate the effectiveness of our method in reducing contextual bias.



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