&gt;  Physics can collect so much data that the generally accepted standard for results is five sigma. There are biases in physics, but it&#x27;s much harder to delude yourself into a five sigma result than a two sigma one--in the end the right answer becomes obvious.<p>That&#x27;s in the case of clear-cut predictions from theory or empirical relations. But bias generally arises in a more subtle fashion than statistics on measurements, though. Even if you have a &quot;5-sigma result&quot;, it still needs to be interpreted, and that&#x27;s where biases can rear their heads. On possible manifestation (though not the only), is if one ascribes to a particular theory, one is generally biased into interpreting those results within the framework of that theory. And if one isn&#x27;t careful, that can lead to diminishing the weight of evidence that conflicts with the theory (e.g., &quot;it&#x27;s 5-sigma, but those data aren&#x27;t actually relevant to this issue&quot;).<p>As an example, one area I&#x27;m actively researching is the emission from molecules in galaxies. We see that some galaxies show enhancements in emission from a specific molecule (HCN). Everyone agrees that the enhancements exist but there&#x27;s wide disagreement on what causes it. And much of the discussion around it parallels people&#x27;s opinions&#x2F;biases about which is more important for a galaxy: how many new stars it is forming versus how active the supermassive black hole is at the galaxy&#x27;s center. The preferred interpretations for the extra HCN emission seems to correlate very well with people&#x27;s prior notions* (which is not surprising). Of course, more data will eventually provide a concrete solution to this question, though what new data are collected is often chosen within an existing framework.<p>* - I&#x27;m sure it&#x27;s true for me, even though I try to mitigate it as much as possible. But we often have trouble recognizing our own biases.