szcf-weiya / ESL-CN

The Elements of Statistical Learning (ESL)的中文翻译、代码实现及其习题解答。
https://esl.hohoweiya.xyz
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Ex. 11.1 #171

Closed szcf-weiya closed 5 years ago

szcf-weiya commented 5 years ago

image

szcf-weiya commented 5 years ago

image

ggg5269 commented 5 years ago

TKS but why choose $\alpha_{00}$ ?

Huyang0625 commented 4 years ago

What's your loss function? and it doesn't make sense $g_m$ is dependent on k

szcf-weiya commented 4 years ago

What's your loss function? and it doesn't make sense $g_m$ is dependent on k

Thanks for your question.

Firstly, I am not sure why you care about the loss function? Secondly, I am sorry the notation here is not very clear, but

Huyang0625 commented 4 years ago

What's your loss function? and it doesn't make sense $g_m$ is dependent on k

Thanks for your question.

Firstly, I am not sure why you care about the loss function? Secondly, I am sorry the notation here is not very clear, but

  • For the regression, actually only 1 output unit, so no dependence on k.
  • For the classification, which can turn out to be multi-response regression, so for each k, we still can establish the equivalence, i.e., for K classification problem, we can get K equivalent PPR models.

Thank you for your reply!

Your answer about the k-classification is helpful!

But I'm still confused how to deal with the learning process of the K-1 PPR, because for different k, $g_m$ share parameters like $alpha$ and which means we can't do the learning for K-1 models respectively. Can we still call it a PPR problem?

szcf-weiya commented 4 years ago

@Huyang0625 replied in http://disq.us/p/264iotd, and update the solution.