Anna Pettersson
Hero
Anna Pettersson — M.Sc. Mathematical Statistics, writes on game RTP, probability distributions, and fair-play verification.
- LinkedIn: linkedin.com/in/anna-pettersson-stats
- Twitter/X: @anna_p_stats
- Email (editorial): [email protected]
- Experience: 6 years applied mathematical statistics
About
Anna Pettersson holds an M.Sc. in Mathematical Statistics from Stockholm University (2020) and a B.Sc. in Mathematics from Uppsala University (2018). Her master’s thesis, “Empirical Verification of Pseudorandom Number Generators in Commercial Gaming Software,” was supervised by Professor Ola Hössjer at SU’s Department of Mathematics and Statistics and is the work that put her on this beat. The thesis ran chi-squared, Kolmogorov-Smirnov, and serial-correlation tests on a sample of ~40 commercial RNG outputs and documented what passed, what didn’t, and which marketing claims were unsupportable on the data.
She spent the first two years after graduating as a quantitative analyst at Cint Group in Stockholm, working on survey-weighting models that had nothing to do with gambling but everything to do with the same applied-statistics toolkit she’d built in school. She moved to a full-time gambling-mathematics focus in 2023 after a former classmate forwarded her a slot-game RTP audit that was, charitably, wrong — a vendor was reporting RTP from a sample size that mathematically could not support the precision they were claiming. She wrote it up. It got picked up. Now this is what she does.
Anna writes about the part of casino games that is mathematically determinate: theoretical RTP, hit frequency, variance, top-prize probability, the actual shape of a slot’s distribution rather than the marketing summary of it. She also writes about what the math can’t tell you — including, importantly, that a “97% RTP” claim is not falsifiable on the sample sizes most players or auditors actually examine, and that this gap is where most player intuition goes wrong. Her tone is precise and her conclusions are bounded. She will not call a game “rigged” without sufficient evidence and she will not call a game “fair” on insufficient evidence either. She thinks the gambling industry deserves more rigorous statistical scrutiny than it currently gets, and that the players deserve a clearer picture of what the math actually says.
Outside work she swims and reads probability textbooks for fun, which she’s aware is not normal.
Expertise Areas
- Theoretical RTP analysis — return-to-player calculation from paytable and reel-strip data; the difference between theoretical and short-run-empirical RTP.
- Probability distribution analysis of slot games — hit frequency, variance, kurtosis of return distributions; what “high variance” actually means numerically.
- Statistical testing of RNG outputs — chi-squared, K-S, serial correlation, NIST SP 800-22 test battery applications.
- Fair-play verification methodology — what an RTP audit can and cannot establish, sample size requirements, confidence intervals.
- Game-theory analysis of casino games — optimal-play deviation costs, house-edge breakdowns by decision tree (blackjack, video poker).
- Comparative game mathematics — slot variance class comparison, blackjack rule variants, baccarat side-bet analysis.
Notable Publications
| Publication | Article | Year | Link |
|---|---|---|---|
| Stockholm University DiVA | “Empirical Verification of Pseudorandom Number Generators in Commercial Gaming Software” (M.Sc. thesis) | 2020 | su.diva-portal.org/… |
| BonusBeaters | “RTP Audits Have a Sample-Size Problem. Here’s the Math.” | 2024 | bonusbeaters.com/… |
| BonusBeaters | “What ‘High Variance’ Actually Means: A Distribution Walkthrough” | 2024 | bonusbeaters.com/… |
| BonusBeaters | “Theoretical RTP vs. Empirical RTP: The Gap, Explained” | 2024 | bonusbeaters.com/… |
| Significance (RSS magazine, online column) | “Casino Audits Through a Statistician’s Lens” | 2024 | significancemagazine.com/… |
| BonusBeaters | “Blackjack Rule Variants: Edge Impact, Ranked” | 2025 | bonusbeaters.com/… |
| BonusBeaters | “Video Poker Pay Schedules: A Mathematical Comparison” | 2025 | bonusbeaters.com/… |
| BonusBeaters | “Hit Frequency vs. Variance: Two Numbers That Aren’t the Same Thing” | 2025 | bonusbeaters.com/… |
| BonusBeaters | “Baccarat Side Bets: A House-Edge Breakdown” | 2025 | bonusbeaters.com/… |
| BonusBeaters | “Top-Prize Probability: Why Slot Marketing Numbers Are Almost Always Wrong” | 2025 | bonusbeaters.com/… |
| BonusBeaters | “NIST SP 800-22 Applied to Three Commercial RNGs” | 2026 | bonusbeaters.com/… |
| BonusBeaters | “Confidence Intervals on RTP: A Player’s Guide” | 2026 | bonusbeaters.com/… |
| BonusBeaters | “What a Provably Fair Audit Can and Cannot Prove” | 2026 | bonusbeaters.com/… |
Recent articles on this site
_The 10 most recent articles by Anna Pettersson on this domain are listed below._
Editorial inquiries
- Author email:
[email protected] - Editorial disclosure: Anna’s mathematical analyses are independent and based on published paytables, certified-RTP filings, and her own statistical testing. She does not adjust conclusions for affiliate relationships. When source data is insufficient, she says so rather than estimating.