4. Binary Classification

Notation:

- (x,y)

- m training example : (x1,y1), (x2,y2), ... , (xm,ym)

- 이때 X : all training set

training set은 각 train sample을 column방향으로 stack.

따라서 X.shape : (n(x), m) 

- n(x) 는 input xm의 feature dimension

 

Y 또한 column 방향으로 stack.

따라서 Y.shape : (1,m)

 

binary classification : input X -> output y(0 or 1)