<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Maximum Likelihood on Chen Kai Blog</title><link>https://www.chenk.top/en/tags/maximum-likelihood/</link><description>Recent content in Maximum Likelihood on Chen Kai Blog</description><generator>Hugo</generator><language>en</language><lastBuildDate>Mon, 26 Aug 2024 09:00:00 +0000</lastBuildDate><atom:link href="https://www.chenk.top/en/tags/maximum-likelihood/index.xml" rel="self" type="application/rss+xml"/><item><title>Probability and Statistics (6): Estimation — MLE, MAP, and the Bias-Variance Story</title><link>https://www.chenk.top/en/probability-statistics/06-estimation-theory/</link><pubDate>Mon, 26 Aug 2024 09:00:00 +0000</pubDate><guid>https://www.chenk.top/en/probability-statistics/06-estimation-theory/</guid><description>&lt;p>Everything we&amp;rsquo;ve built so far — distributions, expectations, limit theorems — assumed we knew the parameters. The Gaussian has mean &lt;span class="math-inline">$\mu$&lt;/span>
 and variance &lt;span class="math-inline">$\sigma^2$&lt;/span>
. The Binomial has &lt;span class="math-inline">$n$&lt;/span>
 trials with success probability &lt;span class="math-inline">$p$&lt;/span>
. But in practice, you don&amp;rsquo;t know &lt;span class="math-inline">$\mu$&lt;/span>
 or &lt;span class="math-inline">$p$&lt;/span>
. You observe data and try to figure them out.&lt;/p>
&lt;p>This is &lt;strong>estimation theory&lt;/strong>: the bridge between probability (where parameters are given) and statistics (where parameters are inferred). It&amp;rsquo;s also where the foundations of machine learning live. Every time you train a model, you are estimating parameters from data. The quality of that estimation determines whether your model generalizes or overfits.&lt;/p></description></item></channel></rss>