xavier roberts-gaal
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xrg.bsky.social
xavier roberts-gaal
@xrg.bsky.social
130 followers 180 following 31 posts
three language models in a trench coat
harvard psych (scholar.harvard.edu/xrg)
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xrg.bsky.social
then you can reply with
November 12, 2025 at 2:42 PM
xrg.bsky.social
We also don't see a very sharp difference in the standard deviations in both demand conditions (which we'd expect if we have reacters and compliers). Distributions look pretty similar.
September 15, 2025 at 6:33 PM
xrg.bsky.social
In short: do you need to worry about experimenter demand ruining *your* online study? Based on our evidence, probably not.

That's good news for the field! As we argue, demand effects appear, at least in their simplest form, to be more phantom than menace (7/8)
meme about demand effects. Darth Maul from Star Wars: The Phantom Menace is igniting his lightsaber in the Naboo palace. The top panel shows Maul igniting the first beam of his lightsaber, with the phrase (from a reviewer, in Comic Sans) "I'm worried these results may be due to demand." The bottom panel shows Maul igniting the second beam of his lightsaber (in dramatic fashion), with the text in large bold font "DEMAND EFFECTS DO NOT EXIST." (Note that we only claim demand effects in online experiments using standard paradigms are weak and/or elusive, and therefore unlikely to bias results. It is a meme :))
September 15, 2025 at 5:19 PM
xrg.bsky.social
We often hear from reviewers: "what about demand effects?" So we developed a method to eliminate them. Something weird happened during testing: We couldn’t detect demand effects in the first place! (1/8)
Summary of design and results from our three studies. (A: Design) Each study used a similar experimental design, measuring both positive and negative demand in an online experiment, with three commonly-used task types (dictator game, vignette, intervention). Our experiments had ns ≈ 250 per cell. (B: Results) Observed demand effects were statistically indistinguishable from zero. The plot shows means and 95% confidence intervals for standardized mean differences derived from frequentist analyses of each experiment and an inverse variance-weighted fixed-effect estimator pooling all experiments (solid bars). Prior measurements of experimenter demand from a previous dictator game experiment (de Quidt et al., 2018; standardized mean difference from regression coefficient) and a meta-analysis primarily including small-sample, in-person studies (Coles et al., 2025; Hedge’s g statistic) are also shown for comparison (striped bars). The main text includes Bayesian analyses that quantify our uncertainty.
September 15, 2025 at 5:19 PM
xrg.bsky.social
the functional form of moral judgment is (sometimes) the nash bargaining solution

new preprint👇
figure 2 from our preprint, reporting the results from two experiments we measure moral judgments about dividing money between two parties and manipulate the degree of asymmetry in the outside options each party has we find that moral judgments track predictions from rational bargaining models like the nash bargaining solution and the kalai-smorodinsky solution in a negotiation context by contrast, in a donation context, moral intuitions completely reverse, instead tracking redistributive and egalitarian principles preprint link: https://osf.io/preprints/psyarxiv/3uqks_v1
May 20, 2025 at 3:08 PM