Notation:
1.m : # training examples
2.
3.y : output variables \”target”variables
4.
5.ith training example : (x(i),y(i))
Flow Path
training set→learning algorithm→h(hypothesis)
Hyposthesis Function
New Living Area → Hypothesis → Estimate Price
Linar function(regression problems)
h(θ)=hθ(X)=θ0+θ1X1+θ2X2(X1 = size X2 = #bedrooms X0=1)
⟹hθ(X)=∑Nk=0θkXk(θi is called parameters)
⟹θTx(n = #featrues)
梯度下降公式推导
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