# Understanding Simpson's Paradox

@article{Pearl2013UnderstandingSP, title={Understanding Simpson's Paradox}, author={Judea Pearl}, journal={ERN: Other Econometrics: Econometric \& Statistical Methods (Topic)}, year={2013} }

Simpson's paradox is often presented as a compelling demonstration of why we need statistics education in our schools. It is a reminder of how easy it is to fall into a web of paradoxical conclusions when relying solely on intuition, unaided by rigorous statistical methods. In recent years, ironically, the paradox assumed an added dimension when educators began using it to demonstrate the limits of statistical methods, and why causal, rather than statistical considerations are necessary to…

## 51 Citations

Simpson's paradox in epistemology and decision theory

- Philosophy
- 2015

I discuss the implications of Simpson’s paradox for epistemology and decision theory. In Chapter One I outline the paradox, focussing on its identification, nature, and type of reasoning that it…

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Among the many peculiarities that were dubbed “paradoxes” by well meaning statisticians, the one reported by Frederic M. Lord in 1967 has earned a special status. Although it can be viewed, formally,…

Lord ’ s Paradox Revisited – ( Oh Lord ! Kumbaya ! ) Judea Pearl

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Among the many peculiarities that were dubbed “paradoxes” by well meaning statisticians, the one reported by Frederic M. Lord in 1967 has earned a special status. Although it can be viewed, formally,…

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It is argued that evidence supports that beliefs are not classical statistical variables and they should, in the general case, be considered as superposition states of disjoint or polar outcomes.

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We address methodological challenges in cross-cultural and cultural psychology. First, we describe weaknesses in (quasi-)experimental designs, noting that cross-cultural designs typically do not…

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- EducationThe British journal of educational psychology
- 2019

It is shown that a common method used to measure school effectiveness is biased against schools that serve students from groups that are historically poor performing, and the ANCOVA is preferred, but otherwise the gain score model may be appropriate.

Simpson's Paradox in COVID-19 Case Fatality Rates: A Mediation Analysis of Age-Related Causal Effects

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- 2021

Causal inference, in particular mediation analysis, can be used to resolve apparent statistical paradoxes; help educate the public and decision-makers alike; avoid unsound comparisons; and answer a range of causal questions pertaining to the pandemic, subject to transparently stated assumptions.

A Bayesian Solution to the M-Bias Problem

- Computer ScienceArXiv
- 2019

The fact that this work is able to offer a solution to the M-Bias problem in Bayesian terms shows that it is indeed possible to represent causal relationships within the Bayesian paradigm, albeit in an extended space.

Reply to commentary by Imai, Keele, Tingley, and Yamamoto concerning causal mediation analysis.

- EconomicsPsychological methods
- 2014

The comment explains the key difference between traditional and modern methods of causal mediation, and demonstrates why the notion of mediation requires counterfactual rather than Bayes conditionals to be properly defined.

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