Wednesday, February 12, 2020
"Less than lethal weapons effect" - a quick thought
Last year, an article by Ariel et al. (2019) landed on my radar. It's of interest to me simply because it does have some relevance to weapons effect research. In summary, police officers are randomly assigned to patrol with or with tasers present. Most of their analyses concentrated on the behavior of the officers. For my purposes, what was interesting was the analysis in which the behavior of suspects was examined - more specifically if there was a difference in propensity for suspects to attack police officers who had tasers than those who did not. The authors found that suspects were significantly more likely to attack an officer carrying a taser than an officer who was not. It's counter-intuitive, for sure. Strikes me as a great way to end up feeling the effects of a taser, as well as face additional charges. Then again, we humans are not necessarily rational animals. So there's that. Thing is that the raw numbers are really not much to write home about. Almost no one in the sample attacked officers in either condition. So the raw numbers were small. The proportions per thousand strike me as underwhelming. So just for kicks, I did a quick and dirty effect size calculation. I had a raw B weight and I had the SE and sample size, so estimating SD was fairly straightforward (SE * sqrtN). I divided the raw B by the estimated SD and ended up with a Cohen's d of 0.176. In other words, this is a fairly small effect. The finding is statistically significant. I have questions of its practical significance. On the positive side, at least this was an effort to test the hypothesis that the mere presence of a weapon (in this case a taser) could influence some form of aggressive behavior in an ecologically valid manner. I'm admittedly pretty jaded about the weapons effect as a phenomenon, but at the very least the research Ariel et al. (2019) conducted showed us a way forward: get out of the lab and get into everyday situations and see if there really is something of interest. We may end up realizing there isn't and likely never was. Or we may end up surprised to find that there was some substance to the old Berkowitz and LePage (1967) experiment. Time will tell.