<img src='https://scrapbox.io/api/pages/nishio-en/o1 Pro/icon' alt='o1 Pro.icon' height="19.5"/> <a href="/en/bias">bias</a> (<a href="/en/Bias">Bias</a>) is the degree to which something is systematically deviated from its true or ideal value when it is measured or estimated. <a href="/en/Variance">Variance</a> (<a href="/en/Variance">Variance</a>) is the degree to which the results of the same measurement or estimation can vary when repeated many times.
<ul>
<li>Bias: How far off the average</li>
<li>Variance: the amount of variation in measurement or estimation results</li>
</ul>
In the darts example, the bias is &quot;which direction the arrow is biased&quot; and the variance is &quot;how much it is scattered&quot;. This is used not only in statistical analysis and machine learning, but also as a general concept when evaluating something.
<a href="https://ja.wikipedia.org/wiki/%E5%81%8F%E3%82%8A%E3%81%A8%E5%88%86%E6%95%A3">Bias and dispersion - Wikipedia</a>
<ul>
<li><a href="/en/Bias%20Variance%20Decomposition">Bias Variance Decomposition</a></li>
</ul>
<a href="https://en.wikipedia.org/wiki/Bias%E2%80%93variance_tradeoff">Bias–variance tradeoff - Wikipedia</a>
<ul>
<li><img src="https://gyazo.com/e31295b3bd913e88c25696ee65ecbcd7/thumb/1000" alt="image"></li>
<li>A picture of a dart you see often.</li>
</ul>
<a href="https://en.wikipedia.org/wiki/Accuracy_and_precision">Accuracy and precision - Wikipedia</a>
<ul>
<li><img src="https://gyazo.com/2830d5ef710e5a3324225b36ffc1fb15/thumb/1000" alt="image"><ul>
<li>This is going to be confusing because the same term pair is used in different ways.</li>
</ul>
</li>
<li><img src="https://gyazo.com/109ac2fd71221157ae91ef6e04db6290/thumb/1000" alt="image"><ul>
<li>I didn&#39;t know this.</li>
</ul>
</li>
</ul>
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Bias and Variance