&gt;  To answer your question, financial e-mails are more likely to be mislabelled as personal than as professional, but not as often as it labels them correctly.<p>Yes, but how likely is each mislabelling? There is no scale to indicate how the colors map onto probabilities.<p>As well as providing a scale, it would be helpful to make the heatmap an <i>annotated heatmap</i>, in which each square is labelled with the corresponding value (perhaps with values below some threshold omitted to reduce clutter).<p>Example: <a href="https:&#x2F;&#x2F;web.stanford.edu&#x2F;~mwaskom&#x2F;software&#x2F;seaborn&#x2F;_images&#x2F;seaborn-heatmap-5.png" rel="nofollow">https:&#x2F;&#x2F;web.stanford.edu&#x2F;~mwaskom&#x2F;software&#x2F;seaborn&#x2F;_images&#x2F;s...</a><p>(from the Seaborn docs: <a href="https:&#x2F;&#x2F;web.stanford.edu&#x2F;~mwaskom&#x2F;software&#x2F;seaborn&#x2F;generated&#x2F;seaborn.heatmap.html" rel="nofollow">https:&#x2F;&#x2F;web.stanford.edu&#x2F;~mwaskom&#x2F;software&#x2F;seaborn&#x2F;generated...</a>)<p>Edit: Consider another question - <i>If an email has the true label &#x27;Financial&#x27;, is it more likely to be mislabeled or correctly labelled?</i> I can guess, but without more knowledge of the scale I can&#x27;t be certain.