The Crud Factor: what’s the average correlation between totally random human traits?

January 24, 2025

We gathered >1 million human correlations spanning personality, demographics, behaviors, and beliefs, which enabled us to investigate an interesting question: is everything correlated with everything? In other words, is the so-called "crud factor" real? Here's our answer. On average, there is almost no correlation between human variables (see image). The average is only r=0.02, with the median even smaller at r=0.01. But this is misleading because it allows positive correlations to be cancel...

What I Learned From One Of The Most Effortful Studies On Behavior Change Ever Conducted

January 13, 2023

I’d like to tell you about one of the biggest and most effortful studies on behavior change ever conducted and its strange findings (that may not even be obvious if you read the paper – I only realized its implications on my 2nd reading!) Let’s begin: The study had 61,000 participants, all with gym memberships. 30 scientists worked in small teams to develop interventions, each aiming to increase gym attendance over 4-weeks. This resulted in 53 interventions to test. A promising setup to figu...