<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Class-Imbalance on Aayush Bajaj's Augmenting Infrastructure</title><link>https://abaj.ai/tags/class-imbalance/</link><description>Recent content in Class-Imbalance on Aayush Bajaj's Augmenting Infrastructure</description><generator>Hugo</generator><language>en</language><copyright>© 2026 Aayush Bajaj</copyright><lastBuildDate>Fri, 10 Jul 2026 08:20:15 +1000</lastBuildDate><atom:link href="https://abaj.ai/tags/class-imbalance/index.xml" rel="self" type="application/rss+xml"/><item><title>Performance Metrics for Machine Learning</title><link>https://abaj.ai/wiki/ml/theory/perf-metrics/</link><pubDate>Thu, 09 Jul 2026 21:02:56 +1000</pubDate><guid>https://abaj.ai/wiki/ml/theory/perf-metrics/</guid><description>&lt;p>a model is only as good as the number you judge it by, and most of the classic modelling disasters are really metric disasters — a fraud detector with \(99.9\%\) accuracy that never flags anything, a medical test tuned to a roc curve nobody deployed at the published threshold.&lt;span class="margin-note" data-note="rule of thumb: before admiring any metric, compute what the trivial constant predictor scores on it">
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this page is the field guide: what each metric measures, what it silently assumes, and which one to reach for when the classes are lopsided, the probabilities matter, or the target is continuous.&lt;/p></description></item></channel></rss>