Mob Mentality

I have an older brother. As any parent with more than one kid will testify, siblings do not always get along. I was particularly devious, though. Even though I was younger, I was waaaaayyyyy more savvy. I used to wrestle him for no reason, pin him down, and torture him. Just like little brothers are supposed to do. When I heard a parent coming to the room, I would quickly flip him over on top of me, hold him so he could not get up, and yell, "HE STARTED IT!" He got in trouble. Every. Single. Time. And I went on about my day.

I did confess this to my mom, eventually. Like 30 years later eventually. She was not amused. While I might be alone in this little rouse I had going, I was not original when I blamed someone else for "starting it". Why do kids do that? Well, it's pretty obvious. Even if we are doing something wrong, we think that if someone else did it first, we are in the clear. Kids are smart that way. 

While this strategy may work in the short-run, it does have long-run consequences. The classic movie The Lion King (1994) contains this great exchange:

Shenzi : [Rolls her eyes and turns to the two yelping and rolling atop each other aggressively]  Will you knock it off?

Banzai : [ed appears to be chewing on Banzai's leg; Banzai sits up]  Well, he started it!

[It is now obvious that Ed is chewing his own leg repeatedly] 

Shenzi : Look at you guys! No wonder we're dangling at the bottom of the food chain!

Banzai : [a string of drool dangles from his chin]  Man, I hate dangling...

While blaming others for our poor behavior may entrench one at the bottom of the food chain, this behavior persists into adulthood. What helps us avoid negative consequences as kids gets engrained in our psyche and stays with us as adults.  


So, what does this have to do with econometrics? Good question. 

I was at a great econometrics conference a week or so ago in New York. As an aside, I met Vitor Possebom (of EconTwitter fame) in person! Vitor's paper along with all the others on the program (save one!) were truly fantastic! As another aside, John Mullahy and I were talking at the conference I hosted a month or so ago. We both repeatedly have similar experiences in this profession when we venture out into the wild. When we are in a room full of "strictly" applied researchers, people often view John and I as "econometricians". However, when we are in a room full of econometricians, people view John and I as most definitely the "applied" guys. Well, attending this conference, I was most certainly the "applied" guy. Yikes! Of course, I have never described myself as an econometrician; just see the first post on this blog!

But, I digress. Returning to the conference. The papers being presenting were truly fantastic, and the people in attendance were all brilliant and extremely nice. So, this post should in no way be construed as a knock on them or their research. However, as I had a lot of time to ponder and pay attention to different things (since I did not follow the details in most of the papers), a trend across the presentations jumped out to me. When it came time to justify a particular choice -- be it an assumption or a functional form or an estimator -- the phrase "as is standard in the literature" kept being tossed about.


Huh. Interesting. What's the point of saying this? Is it meaningful? 

As a cynic, I say that the point of saying it is to accomplish what we all tried to accomplish as kids: avoidance of negative consequences from our behavior. We all know that even with the nicest people in the audience, economics talks are, um, lively ... spirited ... rowdy ... contentious ... alarming ... unhealthy ... psychotic ... Well, since it worked for us as kids, we try to stave off attacks by shouting "THEY STARTED IT!"  

Another explanation for this behavior is that economics (econometrics and other subdisciplines) suffers from mob mentality. Famous people do something, it gets published, we follow along. 


I think the confrontational nature of our discipline gives rise to both these explanations. We emulate what works for others so that our work will hopefully pass scrutiny. But, this is terrible science (IMHO). There are two reasons for this. First, just because someone else did something does not make it right. Even if that person is famous. Even if it is published in a Top 5.  


Our parents try to teach us this as kids. Unsuccessfully, of course.


I warn my PhD students about this, and I have heard others make the same argument. The transition from student to researcher entails transitioning from reading existing works purely to learn to reading to learn and to critique. But, what are we teaching our students who attend our talks and our conferences if they see the "They started it!" defense over and over again?

Second, while researchers that invoke this defense are following the existing literature in some respects, presumably they are advancing the literature along other dimensions. Surely we can forgive a researcher for not tackling all potential issues at once. Of course. I am sympathetic. I am certain my own work often makes this claim. But, as I wrote in a prior post, we do not get an adequate assessment of changes in one dimension if there are errors remaining in another dimension. So, if we attempt to advance science in one respect, but we retain errors in others because it is "standard in the literature", then we risk erroneously judging the quality of the advancement being proposed.


So, what would I have you do instead ... since certainly the profession is not going to become all unicorns and rainbows anytime soon? It is rather simple. Don't use "They started it!" as your first line of defense. Justify the choices made based on their own merits. Explain why the choice was made in prior studies and why it is useful and appropriate in your context. This should be your first line of defense. If you have no plausible rationale for the choices being made, then it is time to rethink your research project as currently constituted. Then, and only then, should you add something like "and this was also done by [insert famous person here]".


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