Understanding Classification Performance

And as long as you are doing any kind of machine learning,  you need to measure and understand its performance.  Since I am doing that now, I noted Jason Brownlee's piece noted below:

How to Report Classifier Performance with Confidence Intervals
by Jason Brownlee  in Machine Learning Process

Once you choose a machine learning algorithm for your classification problem, you need to report the performance of the model to stakeholders. ... This is important so that you can set the expectations for the model on new data. ... A common mistake is to report the classification accuracy of the model alone. .... "