Sports Betting Archive

Karl Whelan’s Sports Betting Page

kwhelan / July 3, 2026

Welcome to my Sports Betting page. Here you’ll find my writing on the economics of sports betting, including blog posts, course materials, useful calculators and code and updates on my forthcoming book.

In recent years, I have published a series of academic papers on the economics of sports betting and prediction markets. You can find them here.

Later this year, I will publish Fine Margins: How Economics Explains Sports Betting. You will be able to find links to how to buy it on this page.

The book draws on my published research, together with lots of new original work based on millions of odds quotes offered by sportsbooks (or bookmakers depending on where you come from). But it is not written for researchers. It is for anyone who wants to understand how the modern sports betting industry really works. Its central argument is that economics provides the ideal toolkit for understanding sportsbooks, betting markets and prediction markets.

The book grew out of a course on the economics of sports betting that I have taught at University College Dublin in recent years. I have made the lecture notes for that course available here.

Unlike the course, however, the book does not require you to do any mathematics or solve calculus problems. And there is no test.

Lecture Notes on the Economics of Sports Betting

kwhelan / July 3, 2026

Sports betting has changed dramatically over the past decade. Following the legalization of sports betting across much of the United States and recent developments in prediction markets, it has become a major industry that raises fascinating questions about economics, finance and public policy.

For the past few years, I have taught a university course on the economics of sports betting at University College Dublin. The course examines topics such as sportsbook pricing, betting exchanges, prediction markets, betting strategy, favourite–longshot bias and market efficiency.

I have made the lecture notes from the course freely available. They are intended for university students, so they contain some mathematics and worked examples, but many readers interested in understanding how betting markets work may also find them useful.

If any instructors are interested in using some of this material, just send me an email.

My forthcoming book, Fine Margins: How Economics Explains Sports Betting, grew out of this course. While it covers many of the same ideas, it is written for a much broader audience. The book explains the economics of sports betting without requiring any mathematics or calculus.

Prediction Markets, Sports Betting

UCD Podcast on Prediction Markets and Sports Betting

kwhelan / July 3, 2026

I recently sat down with Andew Gouldson from the UCD Economics Society to discuss prediction markets, sports betting and some of the research I’ve been doing in this area.

We covered topics including

– How prediction markets such as Kalshi work
– How betting exchanges are essentially the same as prediction markets
– Whether prediction markets can help forecast economic and political events
– The strange non-enforcement of US tax laws on betting winnings
– The favourite–longshot bias in betting and prediction markets
– Why bookmakers\sportsbooks don’t price odds the way people think they do

The full interview is available here

Thanks to Andrew for the invitation.

Prediction Markets, Sports Betting

Predictions about Prediction Markets: NYU Talk

kwhelan / July 3, 2026

In March, I gave a talk on prediction markets at the NYU Stern FinTech Conference. Slides are here.

The talk focused on my recent paper with Constantin Bürgi and Wanying Deng on prices in the Kalshi prediction market. We documented a significant favourite–longshot bias: low-priced contracts tend to produce poor returns for traders, while higher-priced contracts perform considerably better.

I then turned to the future of prediction markets in the United States, a fascinating and highly uncertain topic. The talk discusses pricing accuracy, trading fees and the particular issues that arise when these markets are used for sports betting. Thanks to Kathleen DeRose for inviting me.

My forthcoming book Fine Margins: How Economics Explains Sports Betting, contains a comprehensive treatment of sports betting prediction markets. Drawing on evidence from millions of prediction market trades, it explains how these markets work, how they compare with traditional sportsbooks, and what that evidence tells us about their pricing, trading costs and future prospects.