The ubiquity of the Simpson’s Paradox
Open accessAbstract
The Simpson’s Paradox is the phenomenon that appears in some datasets, where subgroups with a common trend (say, all negative trend) show the reverse trend when they are aggregated (say, positive trend). Even if this issue has an elementary mathematical explanation, it has a deep statistical significance. In this paper, we discuss basic examples in arithmetic, geometry, linear algebra, statistics, game theory, gender bias in university admission and election polls, where we describe the appearance or absence of the Simpson’s Paradox . In the final part, we present our results concerning the occurrence of the Simpson’s Paradox in Quantum Mechanics with focus on the Quantum Harmonic Oscillator and the Nonlinear Schrödinger Equation. We discuss how likely it is to incur in the Simpson’s Paradox and give some concrete numerical examples. We conclude with some final comments and possible future directions.
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The discrepancy between the general trend and colour morph-specific results illustrates Simpson's paradox, where aggregated data masks underlying subgroup patterns.
“The discrepancy between the general trend and the colour morph-specific results illustrates Simpson's paradox, where aggregated data masks underlying subgroup patterns [64].”
From Tiger colour morphs in zoos raise conservation and welfare concerns (2026) · cites this paper as [64]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Cites
The interpretation of interaction in contingency tables
Simpson, E. H. (1951) · Journal of the Royal Statistical Society Series B: Statistical Methodology · doi:10.1111/j.2517-6161.1951.tb00088.x · Cited by 2,301 · cited 2× · see citing works
“In his paper (Simpson 1951), Simpson considered a 2 × 2 × 2 contingency table with attributes A, B, and C and illustrated the paradox using a heuristic example of clinic patients, divided into a Treatment Group and in a No-Treatment group.”
BackgroundMethod
Flagged first, then by citations
Research works printed but not linked: 15
- Bickel, PJ, Hammel, EA, O'Connell, JW: Sex Bias in Graduate Admissions: Data From Berkeley. Science. 187(4175), 398-404 (1975)
- Berestycki, H, Lions, PL: Nonlinear Scalar field equations. Arch. Rational Mech. Anal. 82(3), 313-345 (1983)
- Berestycki, H, Lions, PL, Peletier, LA: An ODE approach to the existence of positive solutions for semilinear problems in R N . Indiana Univ. Math. J. 30(1), 141-157 (1981)
- Berezin, FA, Shubin, MA: The Schrödinger Equation. Translated from the 1983 Russian edition by Yu. Rajabov, DA Leȋtes and NA Sakharova and revised by Shubin. With contributions by G. L. Litvinov and Leȋtes. Mathematics and its Applications (Soviet Series), 66. Kluwer Academic Publishers Group, Dordrecht (1991). ISBN:0-7923-1218-X 81-01 (35J10 35P05 46N50 47F05 47N50)
- Blyth, CR: On Simpson's Paradox and the Sure-Thing Principle. J. Am. Stat. Assoc. 67(338), 364-366 (1972)
- Cialdi, S, Paris, MGA: The data aggregation problem in quantum hypothesis testing. Eur. Phys. J. D. 69, 7 (2015). doi:10.1140/epjd/e2014-50425-7 · DOI
- Good, IJ, Mittal, Y: The Amalgamation and Geometry of Two-by-Two Contingency Tables. Ann. Stat. 15(2), 694-711 (1987)
- Goltz, HH, Smith, ML: Yule-Simpson's Paradox in Research. Pract. Assess. Res. Eval. 15(15), 1-9 (2010)
- Kwong, MK: Uniqueness of positive solutions of u -u + u p = 0 in R n . Arch. Rational Mech. Anal. 105(3), 243-366 (1989)
- Martel, Y, Merle, F: Multi solitary waves for the nonlinear Schrödinger Equations. Ann. I. H. Poincaré. 23(6), 849-864 (2006)
- Norris, F: Can Every Group Be Worse Than Average? Yes (2013). https://economix.blogs.nytimes.com/2013/05/01/can- every-group-be-worse-than-average-yes/. Accessed 1 May 2013 Paris, MGA: Two quantum Simpson's Paradoxes. J. Phys. A. 45, 132001 (2012)
- Pearson, K, Lee, A, Bramley-Moore, L: Genetic (reproductive) selection: Inheritance of fertility in man, and of fecundity in thoroughbred racehorses. Phil. Trans. R. Soc. A. 192, 257-330 (1899)
- Selvitella, A: The Simpson's Paradox in quantum mechanics. J. Math. Phys. 58(3), 37 (2017). 032101
- Shi, Y: Quantum Simpson's Paradox and High Order Bell-Tsileron Inequalities (2012). preprint available at arxiv.org/pdf/1203.2675 · arXiv
- Yule, GU: Notes on the Theory of Association of Attributes in Statistics. Biometrika. 2(2), 121-134 (1903)
Cited by
Sorted by citations
Tiger colour morphs in zoos raise conservation and welfare concerns
Erzinçlioğlu, T. S., Piaz, M. T., Chinpilas, T., Hunnestad, A. V., Godfrey, L., & Fourage, A. (2026) · Discover Animals · doi:10.1007/s44338-026-00163-5
- Authors
- Selvitella, A.
- Affiliations
- McMaster University (CA)
- Corresponding author
- Selvitella, Alessandro
- Venue
- Journal of Statistical Distributions and Applications
- Published
- 2017-03-28
- Volume
- 4
- Issue
- 1
- ISSN
- 2195-5832 (ISSN-L)
- OpenAlex
- W2604002910
- Cited by
- 16
- References
- 1
- Citations by year
- 2026: 3 · 2025: 4 · 2024: 2 · 2023: 1 · 2022: 3 · 2021: 2 · 2020: 1
- FWCI
- 0.19
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Locations
- Journal of Statistical Distributions and Applications (publishedVersion, cc-by)
- RePEc: Research Papers in Economics (submittedVersion)
- Funders
- Canadian Statistical Science Institute (CANSSI)
- Central Michigan University
- Topics
- Physical Sciences › Mathematics › Statistics and Probability › Probability and Statistical Research
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods and Applications
- Physical Sciences › Mathematics › Statistics and Probability › Statistics Education and Methodologies
- Keywords
- Simpson's paradox, election polls, quantum harmonic oscillator, nonlinear Schrödinger equation
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review