Sometimes the job of a data scientist is to know when you don't know enough.

[A] crucial part of justice is equality, and that means, among other things, experiencing criminal justice equally. People who favor policies like Stop and Frisk should experience it themselves. Justice cannot just be something that one part of society inflicts upon the other.

We have to learn to interrogate our data collection process, not just our algorithms.

Justice cannot just be something that one part of society inflicts on the other.

With political messaging, as with most WMDs [Weapons for Math Destruction], the heart of the problem is almost always the objective. Change that objective from leeching off people to helping them, and a WMD is disarmed -- and can even become a force for good.

WMDs, by contrast, tend to favor efficiency. By their very nature, they feed on data that can be measured and counted. But fairness is squishy and hard to quantify. It is a concept. And computers, for all of their advances in language and logic, still struggle mightily with concepts.

In each case, we must ask not only who designed the model but also what they person or company is trying to accomplish.

Nevertheless, many of these models encoded human prejudice, misunderstanding, and bias into the software systems that increasingly managed our lives.

The question, however, is whether we've eliminated human bias or simply camouflaged it with technology.

Some two thousand stone-throwing protesters gathered in the street outside the school. They chanted, "We want fairness. There is no fairness if you don't let us cheat." It sounds like a joke, but they were absolutely serious.