Skip to content
Series
29 posts

Reading CMU 11-785 Introduction to Deep Learning

A lecture-by-lecture reading of CMU 11-785 Spring 2026 that separates its public 28-lecture teaching sequence from the restricted assignment workflow.

Series guide

Neural Nets as Universal Approximators | CMU 11-785 Lecture 2

Spring 2026 Lecture 2 focuses on Boolean functions, how network depth and width affect representational capacity (including a multi-input XOR example), and the hand-off at the end to the next lecture's training problem. This guide follows the official slides and recording and adds a small self-check that does not depend on the enrolled-course grader.

Training I: Learning and Empirical Risk Minimization | CMU 11-785 Lecture 3

Spring 2026 Lecture 3 focuses on how the learning problem is set up (representing inputs and outputs as numbers), the perceptron learning rule and why it does not carry over to multi-layer networks, differentiable divergences, and empirical risk minimization (the loss). This guide follows the official slides and recording and adds a small self-check that does not depend on the enrolled-course grader.

Training II: Gradient Descent | CMU 11-785 Lecture 4

Spring 2026 Lecture 4 focuses on the definitions of derivative and gradient, extrema and second derivatives, gradient descent as repeated steps against the gradient, and the network, input/output representations, and divergence that must be defined before training. This guide follows the official slides and recording and adds a small self-check that does not depend on the enrolled-course grader.

Training III: Backpropagation | CMU 11-785 Lecture 5

Spring 2026 Lecture 5 focuses on layered-network notation, the forward pass, the chain rule and Jacobians (including vector activations), and how the backward pass computes weight and bias derivatives layer by layer. This guide follows the official slides and recording and adds a small self-check that does not depend on the enrolled-course grader.

Training IV: Convergence, Loss Surfaces, and Momentum | CMU 11-785 Lecture 6

Spring 2026 Lecture 6 focuses on convergence of gradient descent (step-size choice on convex and quadratic functions, differences between dimensions), local minima and saddle points, decaying or adaptive learning rates, R-prop, and momentum with Nesterov accelerated gradient. This guide follows the official slides and recording and adds a small self-check that does not depend on the enrolled-course grader.

Training V: SGD and Second-order Methods | CMU 11-785 Lecture 7

Spring 2026 Lecture 7 focuses on incremental SGD and mini-batch updates and trend-based updates such as RMSprop and momentum (second-order methods are only in the slides, not in the recording). This guide follows the official slides and recording and adds a small self-check that does not depend on the enrolled-course grader.

Training VI: Optimizers and Regularization | CMU 11-785 Lecture 8

Spring 2026 Lecture 8 focuses on the choice of divergence (loss), BatchNorm, dropout and other regularization methods, and training tricks such as early stopping (AdaGrad and Adam are not in this recording). This guide follows the official slides and recording and adds a small self-check that does not depend on the enrolled-course grader.

CNNs II | CMU 11-785 Lecture 10

Spring 2026 Lecture 10 focuses on where the CNN comes from (Hubel and Wiesel, Fukushima's Neocognitron), the operations of convolution and pooling layers, and design choices such as filter size, stride and number of channels. This guide follows the official slides and recording and adds a small self-check that does not depend on the enrolled-course grader.

Seq2Seq and Connectionist Temporal Classification | CMU 11-785 Lecture 15

Spring 2026 Lecture 15 focuses on the alignment problem when training sequence models (training with explicit or re-estimated alignments, and the risk of local optima); CTC is only introduced at the very end, with details left to the next lecture. This guide follows the official slides and recording and adds a small self-check that does not depend on the enrolled-course grader.

CTC Blanks and Beam Search | CMU 11-785 Lecture 16

Spring 2026 Lecture 16 focuses on blank symbols and the merging of adjacent repeated symbols, CTC's forward (alpha) probability computation, and pruned approximate decoding (beam search is described only briefly near the end). This guide follows the official slides and recording and adds a small self-check that does not depend on the enrolled-course grader.