Adjusting Bookmaker's Odds to Allow for Overround
Stephen R. Clarke, Stephanie Kovalchik, Martin Ingram · American Journal of Sports Science
Main finding
The power method outperformed normalisation on all three datasets and was comparable to or better than Shin, while always producing valid probabilities.
Limitations
Small journal with an unclear review standard; three specific sports.
Study details
- Authors
- Stephen R. Clarke, Stephanie Kovalchik, Martin Ingram
- Published
- 2017
- Venue
- American Journal of Sports Science 5(6), 45–49
- Status
- Published
- Evidence type
- Peer-reviewed empirical
- Evidence strength
- Limited (our assessment of how much weight the finding can bear)
- Sport
- Tennis, greyhound racing and horse racing
- Markets
- Bookmaker fixed odds
- Method
- Compares additive, normalisation, Shin and power adjustments for overround.
- Sample
- Historical datasets described in the paper.
- Replication
- Consistent with other comparisons of margin-removal methods.
Read the original
doi:10.11648/j.ajss.20170506.12 (opens in a new tab)
Our summary is an original paraphrase for education. Verification: Bibliographic record checked against publisher, index or author listings. Checked 2026-10-25.