Allen B. Downey

Boston, Massachusetts

Professor of Computer Science at Olin College

Allen Downey is a Professor of Computer Science at Olin College of Engineering. He has taught at Wellesley College, Colby College and U.C. Berkeley. He has a Ph.D. in Computer Science from U.C. Berkeley and Master's and Bachelor's degrees from MIT.

Think Python Think Python
by Allen B. Downey
August 2012
Print: $39.99
Ebook: $31.99

Think Complexity Think Complexity
by Allen B. Downey
March 2012
Print: $29.99
Ebook: $23.99

Think Stats Think Stats
by Allen B. Downey
July 2011
Print: $29.99
Ebook: $16.99

Allen B. blogs at:

The Red Line problem

May 09 2013

I've just added a new chapter to Think Bayes; it is a case study based on a class project two of my students worked on this semester.  It presents "The Red Line Problem," which is the problem of predicting the time until the next train arrives, based on the number… read more

Software engineering practices for graduate students

May 06 2013

Recently I was talking with an Olin student who will start graduate school in the fall, and I suggested a few things I wish I had done in grad school.  And then I thought I should write them down.  So here is my list of Software Engineering Practices All Graduate… read more

The Price is Right Problem: Part Two

April 24 2013

This article is an excerpt from Think Bayes, a book I am working on.  The entire current draft is available from http://thinkbayes.com.  I welcome comments and suggestions. In the previous article, I described presented The Price is Right problem and a Bayesian approach to estimating the value of a showcase of prizes.… read more

The price is right

April 22 2013

On the reddit statistics forum, I recently posted a link to my tutorial on Bayesian statistics.  One of my fellow redditors drew my attention to this article, which uses pymc to do a Bayesian analysis of The Price is Right.  He or she asked how I would solve this problem… read more

The Price is Right Problem

April 22 2013

This article is an excerpt from Think Bayes, a book I am working on.  The entire current draft is available from http://thinkbayes.com.  I welcome comments and suggestions. The Price is Right Problem On November 1, 2007, contestants named Letia and Nathaniel appeared on The Price is Right, an American game show.… read more

Freshman hordes regress to the mean

April 09 2013

More nones, no nuns For several years I have been following one of the most under-reported stories of the decade: the fraction of college freshmen who report no religious preference has tripled since 1985, from 8% to 24%, and the trend is accelerating. Two years ago I wrote Freshman hordes more… read more

Belly Button Biodiversity: Part Four

March 22 2013

March 22, 2013 Well, I've started testing the predictions I made in my previous post, and exactly as I expected and deserved, I am getting killed.  The actual results pretty consistently show more species than I predicted, sometimes way more. I have started the process of debugging the problem.  Of… read more

Belly Button Biodiversity: Part Three

February 22 2013

This is part three of a series of articles about a Bayesian solution to the Unseen Species problem, applied to data from the Belly Button Biodiversity project. In Part One I presented the simplest version of the algorithm, which I think is easy to understand, but slow.  In Think Bayes I present some ways to optimize it.  In… read more

Belly Button Biodiversity: Part Two

February 08 2013

This is part two of a series of articles about a Bayesian solution to the Unseen Species problem, applied to data from the Belly Button Biodiversity project. In Part One I presented the simplest version of the algorithm, which I think is easy to understand, but slow.  In Think Bayes… read more

Webcast: There's Only One Test
October 04, 2011
Can I use a t-test if my data are non-normal? What if the sample size is small? What's an exact test? And how many tests are there, anyway? People working with real data are often confused about hypothesis testing and paralyzed by the number of tests...

Webcast: Bayesian Statistics Made Simple
October 26, 2012
Join Allen Downey, author of Think Stats: Probability and Statistics for Programmers for an introduction to Bayesian statistics using Python. Bayesian statistical methods are becoming more common and more important, but there are not many resources...

Allen B. Downey