Do Gun-Purchase Waiting Periods Save Lives?

That is the title of a paper by Arnold and Priestley (2025). They examine whether gun purchase wait periods impact suicide rates using both variation in gun laws by state over time as well as variation in a county’s distance to the nearest state without a waiting period. First, some background on US gun purchase…

More Randomization Problems

Randomized clinical trials (RCTs) are the “gold standard” for medical studies. Nevertheless, even RCTs have their problems. An NBER working paper by Ludwig, Marcotte and Norberg points highlights some of these issues. The authors examine whether or not anti-depressants reduce suicide rates (they find that anti-depressants do reduce suicide rates). Unfortunately, using data from RCTs…