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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
GNU General Public License v3.0
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Ex. 4.2 #108

Closed szcf-weiya closed 5 years ago

szcf-weiya commented 6 years ago

selection_680 selection_681

szcf-weiya commented 6 years ago

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szcf-weiya commented 6 years ago

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szcf-weiya commented 6 years ago

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szcf-weiya commented 6 years ago

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szcf-weiya commented 6 years ago

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szcf-weiya commented 6 years ago

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szcf-weiya commented 5 years ago

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bxdd commented 3 years ago

作者在第二问用到的分块知识较复杂，对代数基础要求比较高，这里提供一种直接求导较简单的方法： image

alpaca202204 commented 1 year ago

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（*）式应该是log（N2/N1）吧 （d）的计算没看懂哎

szcf-weiya commented 1 year ago

@alpaca202204 谢谢，确实是 log(N2/N1)。(d) 其实就是重复一下 (b) 的过程，注意只有 y 变了。