Accuracy is one of the metrics used to evaluate a predictive model. This word is also an every-day English word. How this word is interpreted/communicated in meetings between business users and ML engineers can have significant implications. While there are many other metrics such as precision, recall, F1 score, and so on[ 1 ], most business users relate to accuracy. Many a time, this metric, accuracy can be misleading. Decisions based on an on-the-surface evaluation of any single model metric can result in losses. Let me clarify what I mean. A bank wants to predict who is likely to default on a loan and decide if it should disburse the loan or not. Now, what is an acceptable accuracy for the predictive model? Can I use a model that has 20% accuracy? Is 90% good enough to put my models in production? Well, it depends. Is 95 % accuracy good enough? Accuracy is the number of records that are correctly classified. Let us say, we have 95% accuracy. The bank sees about two defa...