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Technical

Teacher Forcing in Sequence Models

Teacher forcing is a training trick for sequence models where the true previous token, not the model's own guess, is fed in as the next input.

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Technical

Scheduled Sampling and Exposure Bias

Exposure bias is the gap that appears when a model trained only on perfect prefixes must, at inference, condition on its own imperfect outputs.

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Technical

Focal Loss for Imbalanced Detection

Focal loss is a modified loss function that down-weights easy examples so a detector can focus on the hard, rare ones.

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Technical

Test-Time Augmentation

Test-time augmentation (TTA) runs a trained model on several altered versions of the same input and averages the predictions.

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Technical

Negative Sampling and Noise Contrastive Estimation

Negative sampling and Noise Contrastive Estimation (NCE) are tricks that let models learn over huge vocabularies without computing a costly full softmax.

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Technical

InfoNCE and SimCLR Objectives

InfoNCE is the contrastive loss that teaches a model to pull matching pairs together and push mismatched pairs apart in embedding space.

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Technical

Stochastic Weight Averaging

Stochastic Weight Averaging (SWA) takes a simple average of the model's weights from several points late in training instead of just keeping the final…

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Technical

Lookahead and Lion Optimizers

Lookahead and Lion are two modern twists on neural-network optimization.

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Technical

Mixup and CutMix Augmentation

Mixup and CutMix are data-augmentation methods that create new training examples by blending two images and their labels.

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Technical

Online and Hard Negative Mining

Hard negative mining picks the most informative, difficult-to-distinguish examples to train on instead of wasting effort on easy ones the model already gets…

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Technical

Capsule Networks

Capsule networks are a neural architecture that groups neurons into 'capsules' that output vectors encoding both whether a feature exists and its pose…

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Technical

Echo State Networks and Reservoir Computing

Reservoir computing is a clever shortcut for training recurrent networks: leave a large, randomly connected 'reservoir' of neurons fixed and only train…

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