- tags
- Machine Learning, books

## 1. What’s machine learning

There are several types of learning, Supervised Learning, Unsupervised Learning, Semi-Supervised Learning, Reinforcement learning.

## Notes

### Capital Sigma Notation The summation over a collection X = {x 1 , x 2 , . . . , x n−1 , x n } or over the attributes of a vector

### Capital Pi Notation A notation analogous to capital sigma is the capital pi notation. It denotes a product of elements in a collection or attributes of a vector

### Derivatives for basic functions are known. For example if f (x) = x 2 , then f 0 (x) = 2x; if f (x) = 2x then f 0 (x) = 2; if f (x) = 2 then f 0 (x) = 0 (the derivative of any function f (x) = c, where c is a constant value, is zero).

Given this, finding local minima in a function would be finding points (x) in the domain for which f’(x) = 0, and for which f’(x+1) > 0 and f’(x-1) > 0.

elliottBeautifulDifferentiation: Beautiful Differentiation