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Technical

Attention Rollout and Head Pruning

Attention rollout is a method for tracing how information flows through a Transformer's stacked attention layers to explain which input tokens influence…

2 min readRead
Technical

Second-Order Optimization and Newton Methods

Second-order optimization uses curvature information (the Hessian matrix of second derivatives) to take smarter steps toward a minimum, not just the slope.

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Technical

RMSNorm and Pre-Layer Normalization

RMSNorm is a lightweight normalization layer that rescales activations by their root mean square, and pre-layer normalization places that step before each…

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Technical

SwiGLU and Gated Activations

SwiGLU is a gated activation function that multiplies one linear projection of the input by a Swish-activated second projection, acting as a learnable…

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Technical

Squeeze-and-Excitation Networks

Squeeze-and-Excitation (SE) blocks let a convolutional network learn how much to weight each feature channel, recalibrating them based on global context.

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Technical

Warmup and Cosine Annealing Schedules

Warmup gently ramps the learning rate up from near zero before training, then cosine annealing smoothly decays it back down following a cosine curve.

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Technical

Cyclical Learning Rates

Cyclical learning rates repeatedly cycle the learning rate up and down between a lower and upper bound instead of only decaying it.

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Technical

Sharpness-Aware Minimization

Sharpness-Aware Minimization (SAM) is an optimization method that seeks not just a low loss but a low loss across a whole neighborhood of weights — a flat…

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Technical

Linear Probing and Frozen Feature Evaluation

Linear probing tests how good a pretrained model's internal representations are by freezing the network and training only a simple linear classifier on top.

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Technical

DenseNet and Dense Connectivity

DenseNet is a convolutional network where every layer receives the feature maps of all preceding layers as input.

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Technical

Bottleneck Architectures

A bottleneck architecture squeezes data through a narrow intermediate layer before expanding it again, forcing the network to learn compact, efficient…

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Technical

Gradient Accumulation

Gradient accumulation lets you simulate a large batch size on limited GPU memory by summing gradients over several small mini-batches before updating…

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