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world:optimal-classifier [2023/11/04 12:23]
rdouc [Bayes Optimal Classifier]
world:optimal-classifier [2023/11/04 14:03] (current)
rdouc [Bayes Optimal Classifier]
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 where $\sf{F}$ is the set of measurable functions from $\rset^k$ to $[1:p]$ where we equip $\rset^k$ with the $\sigma$-field $\mcbb(\rset^k)$ and $[1:p]$ with the $\sigma$-field $\mc{P}([1:​p])$. ​ where $\sf{F}$ is the set of measurable functions from $\rset^k$ to $[1:p]$ where we equip $\rset^k$ with the $\sigma$-field $\mcbb(\rset^k)$ and $[1:p]$ with the $\sigma$-field $\mc{P}([1:​p])$. ​
  
-<WRAP center round tip 80%>+<WRAP center round tip 90%>
 **__Proposition__** ​ **__Proposition__** ​
 $$ $$
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 Moreover the inequality above becomes an equality for $\phi=\phi^\star$ which satisfies the property: ​ Moreover the inequality above becomes an equality for $\phi=\phi^\star$ which satisfies the property: ​
 $$ $$
-\phi^\star(X)= \argmin_{i \in [1:p]} \PP(Y \neq i|X)=\argmax_{i \in [1:p]} \. This|X)+\phi^\star(X)= \argmin_{i \in [1:p]} \PP(Y \neq i|X)=\argmax_{i \in [1:p]} \PP(Y=i|X)
 $$ $$
-since $\PP(Y \neq i|X)=1-\PP(Y=i|X)$. This concludes the proof. ​+where the last equality follows from the identity ​$\PP(Y \neq i|X)=1-\PP(Y=i|X)$. This concludes the proof. ​
world/optimal-classifier.1699096992.txt.gz · Last modified: 2023/11/04 12:23 by rdouc