Description du poste
Last year, I posted the results of a self-experiment on Melatonin. This year, I ran another self-experiment from January to June, the results of which I'll lay out in this post.
Tl;dr: I randomized three interventions on a daily basis and tracked several metrics throughout the day to see what the short-term effects are. Interventions centered on coffee intake, meditation, and doing jumping jacks, all of which happened primarily in the morning. Caveats apply (n = 1, nothing was blinded, some analyses slightly differ from my "preregistration"). The main results:
• Caffeine had a range of positive effects on me:• Improved mood (+0.8 on a 0-10 scale, p < 0.0001) • Improved energy level (+1.0 on a 0-10 scale, p < 0.0001)• Reduced distraction (-0.7 on a 0-5 scale, p < 0.0001)• Across all days, productivity rose by +9% through caffeine, but insignificant (p = 0.38); I then performed a sensible-but-not-preregistered little p-hack, filtering for the types of days where the my productivity metric is most meaningful, and obtained +19% (p = 0.01)• Improved subjective job performance (+0.5 on 0-5 scale, p = 0.009)• Caffeine intake slightly delayed time to fall asleep (from 28 to 31 minutes on average, p = 0.014) and perhaps reduced subjective sleep quality (7.3 → 7.1 on a 0-10 scale, p = 0.21)• Decaf showed ~none of the above effects, with the possible exception of productivity, which saw an increase of +20% across all days compared to the control group, but not statistically significant (p = 0.18)• Doing 50 jumping jacks in the morning may perhaps improve my productivity (+20%, p = 0.03) (but this turns to +14%, p = 0.08 when applying the sensible-but-not-preregistered adjustment mentioned above)• 10-20 minutes of meditation a day had no measurable short-term effects on anything
I performed the analysis by hand via hypothesize.io. Zero AI involvement went into the analysis or this post. (Although I'm not even sure if that's necessarily a good thing at this point)
Experiment S