Noise by Daniel Kahneman, Olivier Sibony, and Cass Sunstein

This is a book that takes a deep dive into unconscious bias, and tries on a number of different levels to point it out, and to help the reader to see that no one escapes this one, we all succumb to it to a greater or lesser extent, and the trick is to constantly be on the look out for it and to try to counterbalance it. This scattergun variability in judgments of all kinds, from court sentencing to insurance underwriting to medical diagnosis, is what the authors call, well, noise. Like its more famous cousin, bias, noise is an error in judgment. The authors distinguish between the two using a shooting-range metaphor. If all the shots land systematically off-target in the same direction, that’s bias; by contrast, noise is all over the place. Some of the shots might even be on target, because the issue here is not missing the target but a lack of consistency. Given the same facts, one criminal gets life and another who is equally guilty gets off. Which brings us to the other significant distinction between bias and noise: to detect bias, you have to know what the right answer is, or to use the book’s metaphor, you have to be standing at the front of the target, so you can see the bullseye. Noise requires no such particulars. It is detectable no matter which side of the target you’re standing on, since all you need to know is whether or not there is variability. One insurance company executive estimated the annual cost of noise in underwriting in the hundreds of millions of dollars. And you should want to detect noise, the authors argue, because it is not only unfair, it can be hugely costly--in money, in opportunity, and in human capital.