Archive for the ‘Bayes – Bayesian Inference’ Category

If I test positive for COVID, am I infected?

May 27, 2020

The answer may surprise you, and it has big implications for test & trace.

In a prior post, we reported that “Asymptomatics” are not rushing to get tested and provided some subjective reasons why that might be (e.g. no doctor referral, high hassle factor, privacy concerns).

OK, let’s up our game a notch or two and throw some math & economics at the problem.


I’m a fan of “Freakonomics” … the popular call sign for a discipline called Behavioral Economics … the study of the rationality that underlies many seemingly irrational decisions that people sometimes make.

And, in my strategic business analytics course, I used to teach something called Bayesian Inference … a way to calculate probabilities by combining contextual information (called “base rates” or “priors”) with case-specific observations (think: testing or witnessing).

Today, we’ll connect Freakonomics and Bayesian Inference and apply them to the COVID testing situation…


Vindication for the CFP selection committee (and Rev. Bayes)

January 13, 2015

Hooray.  Bucks 42, Ducks 20

The College Football Playoff Selection Committee took a lot of heat when they seeded OSU in the tourney.

Well, last nite’s game vindicated the committee.

Also vindicated was Rev. Thomas Bayes.

You know, the guy who developed Bayes’ Theorem.

Here’s what I mean …


In my Strategic Business Analytics course we cover Bayesian Inference … applications of Bayes’ Theorem … how to statistically adjust your so-called “prior beliefs” when you get new evidence.

Even I admit that sometimes the subject can get a bit dry …

So let’s bring it to life…