Kahneman and Tversky’s (1979) “Prospect Theory” article is the most cited paper in the history of economics, and it won Kahneman the Nobel Prize in 2002. Among other things, it predicts that people are risk seeking for unlikely gains (e.g., they pay more than $1 for a 1% chance of $100) but risk averse for…
Author: Uri Simonsohn
[123] Dear Political Scientists: The binning estimator violates ceteris paribus
This post delves into a disagreement I have with three prominent political scientists, Jens Hainmueller, Jonathan Mummolo, and Yiqing Xu (HMX), on a fundamental methodological question: how to analyze interactions in observational data? In 2019, HMX proposed the "binning estimator" for studying interactions, a technique that is now commonly used by political scientists. I argued…
[122] Arresting Flexibility: A QJE field experiment on police behavior with about 40 outcome variables
A forthcoming paper in the Quarterly Journal of Economics (QJE), "A Cognitive View of Policing" (htm), reports results from a field experiment showing that teaching police officers to "consider different ways of interpreting situations they encounter" led to "reductions in use of force, [and] discretionary arrests" (abstract). In this post I explain why, having spent…
[121] Dear Political Scientists: Don't Bin, GAM Instead
There is a 2019 paper, in the journal Political Analysis (htm), with over 1000 Google cites, titled "How Much Should We Trust Estimates from Multiplicative Interaction Models? Simple Tools to Improve Empirical Practice". The paper is not just widely cited, but is also actually influential. Most political science papers estimating interactions now-a-days, seem to…
[120] Off-Label Smirnov: How Many Subjects Show an Effect in Between-Subjects Experiments?
There is a classic statistical test known as the Kolmogorov-Smirnov (KS) test (Wikipedia). This post is about an off-label use of the KS-test that I don’t think people know about (not even Kolmogorov or Smirnov), and which seems useful for experimentalists in behavioral science and beyond (most useful, I think, for clinical trials and field…
[119] A Hidden Confound in a Psych Methods Pre‑registrations Critique
A forthcoming paper in Psych Methods (.pdf) had a set of coders evaluate 300 pre-registrations in terms of how informative they were about several study attributes (e.g., hypotheses, analysis, DVs). The authors analyzed the subjective codings and concluded that many pre-registrations in psychology, especially those relying on the AsPredicted template, provide insufficient information., Central to…
[117] The Impersonator: The Fake Data Were Coming From Inside the Lab
A previous version of this post was supposed to go live in January 2019. But the day before it was scheduled, the Data Colada team (Uri, Leif, and Joe) received an email that we took to be a potential death threat. After discussions with the local police, the FBI, and our families, we decided to…
[115] Preregistration Prevalence
Pre-registration is the best and possibly only solution to p-hacking. Ten years ago, pre-registrations were virtually unheard of in psychology, but they have become increasingly common since then. I was curious just how common they have become, and so I collected some data. This post shares the results. The data From the Web of Science…
[108] MRAN is Dead, long live GRAN
Microsoft has been making daily copies of the entire CRAN website of R packages since 2014. This archive, named MRAN, allows installing older versions of packages, which is valuable for reproducibility purposes. The 15,000+ R packages on CRAN are incessantly updated. For example, the package tidyverse depends on 109 packages; these packages accumulate 63 updates, just…
[103] Mediation Analysis is Counterintuitively Invalid
Mediation analysis is very common in behavioral science despite suffering from many invalidating shortcomings. While most of the shortcomings are intuitive [1], this post focuses on a counterintuitive one. It is one of those quirky statistical things that can be fun to think about, so it would merit a blog post even if it were…