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Placeholder.  Testing Chinese language input.  尝试中文输入。
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Hypothesis Testing
  
*Instructor's comment: I am not sure it's a good idea to put chinese characters in the title of the page. It's probably best to stick with English only for the title of the page. -pm
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PR 的目标是将新的sample进行分类。
*Page displays ok in my safari browner. -pm
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分类的决定通过
<math> \theta </math>
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假设sample是rv, 其conditional density来自其类别
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如果知道conditional density, pr的问题就变成statistical hyp testing 的问题
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如下假设sample属于两个class其中一个、知道conditional density 和 prior
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Bayes Decision Rule for Minum Error
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假设X是个observation vector.  
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g_i(X) 是X 来自 omega_i 的 Posterior probability 
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Decision rule: 如果 个g_1(X) > g_2(X),就选 omega1, 不然选 omega 2
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据Bayes theorem, decision rule 可以用likelihood ratio 表示
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<math>\begin{align}
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&  g_1(X) > g_2(X) \\
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\Rightarrow & P(\omega_1|X) > P(\omega_2|X) \\
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\Rightarrow &  \frac{P(X|\omega_1)P(\omega_1)}{P(X)} > \frac{P(X|\omega_2)P(\omega_2)}{P(X)} \\
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\Rightarrow & P(X|\omega_1)P(\omega_1) > P(X|\omega_2)P(\omega_2)
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\end{align}
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</math>
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Neyman -- Pearson Test

Revision as of 14:09, 1 May 2014

Hypothesis Testing

PR 的目标是将新的sample进行分类。 分类的决定通过 假设sample是rv, 其conditional density来自其类别 如果知道conditional density, pr的问题就变成statistical hyp testing 的问题 如下假设sample属于两个class其中一个、知道conditional density 和 prior

Bayes Decision Rule for Minum Error 假设X是个observation vector. g_i(X) 是X 来自 omega_i 的 Posterior probability Decision rule: 如果 个g_1(X) > g_2(X),就选 omega1, 不然选 omega 2 据Bayes theorem, decision rule 可以用likelihood ratio 表示

$ \begin{align} & g_1(X) > g_2(X) \\ \Rightarrow & P(\omega_1|X) > P(\omega_2|X) \\ \Rightarrow & \frac{P(X|\omega_1)P(\omega_1)}{P(X)} > \frac{P(X|\omega_2)P(\omega_2)}{P(X)} \\ \Rightarrow & P(X|\omega_1)P(\omega_1) > P(X|\omega_2)P(\omega_2) \end{align} $ Neyman -- Pearson Test

Alumni Liaison

Correspondence Chess Grandmaster and Purdue Alumni

Prof. Dan Fleetwood