Until one day there is a cold snap. Your average error rise. This happens because of the mean squared error. To compute mean squared error, … Read More

A binary classifier is like a gatekeeper. It’s on guard at the door to your workflow, it determines whether a patient receives an MRI, a … Read More

Is this a fraud? Will I get cancer from this tumor? Is this email spam? It sounds like a simple yes/no question, but the answer … Read More

Accuracy is the deadliest lie in data science. You train a model to spot some kind of rare fraud. It is ninety-nine percent accurate! That’s … Read More

Each diagnostic test you perform is actualy a guessing game, but on partial information. Patient may or may not be ill. The test may or … Read More

Two radiologists are asked to look at a chest X-ray. They both looks at it. One spots a shadow that she think looks like cancer. … Read More

You have six carefully made questions that you distribute to employee in a survey, hoping that you’ll measure their engagement. You tabulate response and calculate … Read More

Your data isn’t neatly distributed in some classic form. It’s not a nice, tidy bell curve; it’s a little too messy. And then traditional stats … Read More

Sometimes you find that certain groups behave very different than the larger population they are part of. That the sum of several things is drastically … Read More

So you conduct an experiment, gather some data, get a number and it seems high. Is it noise? Or is it a real signal? This … Read More