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Fundamentals

Stochastic Gradient Descent with Momentum

Momentum is a tweak to gradient descent that accumulates a running average of past gradients, letting optimization roll faster through valleys and dampen…

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Fundamentals

Nesterov Accelerated Gradient

Nesterov Accelerated Gradient (NAG) is a smarter form of momentum that peeks ahead before computing the gradient, giving it a corrective look-ahead.

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Fundamentals

Triplet Loss and Metric Learning

Triplet loss teaches a neural network to place similar items close together and dissimilar items far apart in an embedding space.

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Fundamentals

Label Smoothing

Label smoothing is a simple regularization trick that softens hard one-hot training targets, telling the model the correct answer is very likely but not 100…

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Fundamentals

Long Short-Term Memory Cells

Long Short-Term Memory (LSTM) cells are a special kind of recurrent neural network unit built to remember information across long sequences.

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Fundamentals

K-Means Clustering

K-Means is an unsupervised algorithm that automatically sorts data into K groups by finding cluster centers.

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Fundamentals

K-Nearest Neighbors

K-Nearest Neighbors (KNN) classifies a new data point by looking at the K closest examples and taking a majority vote.

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Fundamentals

Logistic Regression

Logistic regression predicts the probability that something belongs to a class, like spam or not spam, by squashing a weighted sum through an S-shaped curve.

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Fundamentals

Naive Bayes Classifiers

Naive Bayes is a fast, probabilistic classifier built on Bayes' theorem that assumes every feature is independent given the class.

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Fundamentals

ROC Curves and AUC

An ROC curve plots how well a classifier separates two classes across every possible decision threshold, and AUC compresses that whole curve into one number.

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Fundamentals

Confusion Matrices

A confusion matrix is a simple table that breaks a classifier's predictions into correct and incorrect counts for each class.

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Fundamentals

Bias-Variance Tradeoff

The bias-variance tradeoff explains why a model can fail by being too simple or too complex.

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