← Every exhibit

Figure 2From “What is Simpson's paradox?”

A pooling decision record

Write down the question, the third variable and the answers to three tests before choosing the pooled or the split table.

Cite Embed

Figure 2A pooling decision record

A six-column worksheet for a pooling decision: the question, the third variable, whether it is linked to both the groups and the outcome, whether the action can change it, whether it closes every path into the action, and which table to read.QuestionWhich action,which outcome?Third variableWhat splits thedata?Linked to bothTo the groups andthe outcome?Moved by actionCan the actionchange it?Paths closedDoes it closeevery path in?TablePooled, split orneither?Split if the action cannot change it and it closes every path in; pool if no path in is open; otherwise measuremore.

Source: Author's decision worksheet. The linked-to-both field follows Simpson (1951), p. 241; the moved-by-action and paths-closed fields follow Pearl (2014), p. 11; the decision follows Pearl (2014), pp. 11 to 12. The fields are reader inputs; no company data is supplied.

PNG4:3, 1600 × 1200, with the title, the source line and the attribution set in the image isoglu-2026-what-is-simpsons-paradox-fig02.png

Source and evidence

Each line names a claim related to this exhibit, its source, and how it was checked.

  • B SPX-OWN-C3 A pooling decision record: the question (action and outcome), the third variable, whether it is linked to both the groups compared and the outcome, whether the action can change it, whether it closes every path into the action, and the table to read; split if the action cannot change it and it closes every path in, pool if no path in is open, otherwise measure more. Illustrated with invented discounts for two sales teams (team A 10% on 30 small and 20% on 70 large deals, 17% overall; team B 12% on 80 small and 22% on 20 large, 14% overall), routing by deal size, and a team that enlarges deals so that deal size becomes partly downstream of the team (wording after G5 N9); the author's examples, untested.Author worksheet grounded in SIM51-C4, PRL14-C6 and PRL14-C7; untested

Grades: A, verified against the printed page of the primary source · B, primary source, text layer only · C, authoritative secondary · D, reported.

From the essay

Cite or embed

APA 7

Isoglu, S. (2026). A pooling decision record [Figure]. isoglu.com. https://isoglu.com/insights/exhibits/isoglu-2026-what-is-simpsons-paradox-fig02/

BibTeX
@misc{isoglu-2026-what-is-simpsons-paradox-fig02,
  author = {Isoglu, Sinan},
  title = {{A pooling decision record}},
  year = {2026},
  howpublished = {Figure 2, isoglu.com},
  url = {https://isoglu.com/insights/exhibits/isoglu-2026-what-is-simpsons-paradox-fig02/},
  note = {From the essay {What is Simpson's paradox?}}
}
Embed this exhibit

Copy this HTML to use the PNG exhibit on your site with its source line and a link back to the exhibit page.

<figure>
  <a href="https://isoglu.com/insights/exhibits/isoglu-2026-what-is-simpsons-paradox-fig02/">
    <img src="https://isoglu.com/social/isoglu-2026-what-is-simpsons-paradox-fig02.png" alt="Figure 2: A pooling decision record" width="3200" height="2400">
  </a>
  <figcaption>Figure 2: A pooling decision record. Source: Author&#39;s decision worksheet. The linked-to-both field follows Simpson (1951), p. 241; the moved-by-action and paths-closed fields follow Pearl (2014), p. 11; the decision follows Pearl (2014), pp. 11 to 12. The fields are reader inputs; no company data is supplied. <a href="https://isoglu.com/insights/exhibits/isoglu-2026-what-is-simpsons-paradox-fig02/">View exhibit</a>.</figcaption>
</figure>

Related exhibits

Figure 1Figure

Women admitted at Berkeley in fall 1973, against two expected counts

What is Simpson's paradox?

Figure 2Figure

A nudge test record

What is a nudge?

Figure 2Figure

An analysis decision record

What is p-hacking?

Every exhibit

Contact

Bring the question you're working on.

Research, a guest lecture, or a commercial question.