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Marc F. Bellemare Posts

Writing Matters

Having spent last weekend in in my hometown for the Canadian Economics Association/Canadian Agricultural Economics Society annual meetings, I was asked by a classmate from way back to give a short talk about writing in economics (especially for people for whom English is a second language) to the participants of a writing retreat for economics graduate students across all four of Montreal’s universities.

Here are the slides of that short talk, in which I tried to go beyond what I had already said in Doing Economics.

Yair Mundlak and the Fixed Effects Estimator

That’s the title of my latest article, coauthored with Dan Millimet, and which just came out in the spring issue of the Journal of Economic Perspectives. Here’s the abstract:

We discuss Yair Mundlak’s (1927–2015) contribution to econometrics through the lens of the fixed effects estimator. We set the stage by discussing Mundlak’s life and his seminal 1961 article in the Journal of Farm Economics, showing how it was looking at the right application—the study of agricultural productivity, which had hitherto been thought to be marred by the presence of management bias—that led Mundlak to use the fixed effects estimator. After discussing Mundlak’s contribution, we briefly discuss the historical economic and statistical contexts in which he made that contribution. We then highlight the dialogue that took place between the proponents of fixed versus random effects and discuss how Mundlak settled the debate in his 1978 Econometrica article. We conclude by discussing how, between fixed and random effects, the fixed effects estimator won the day, becoming the de facto estimator of choice among applied economists because of the Credibility Revolution, culminating in the popularity nowadays of difference-in-differences designs and of two-way fixed effects estimators.

I have learned a lot while working on this article. Like many people, I thought Mundlak himself had developed the fixed effects estimator. But that turned out not to be true: The estimator was already available; what Mundlak did which forever associated his name with the fixed effects estimator was to find the right application for it. Having recently published an article in which my coauthors and I present the first application of an estimator to economics, this was very encouraging.

Quality vs. Quantity in Publishing

As a result of having served as editor of Food Policy (2015-2019) and the American Journal of Agricultural Economics (2019-2023), I’ve been asked to write a lot of tenure and promotion letters these past ten years. This has given me a chance to reflect on how people can be successful in agricultural economics. Given that, I thought I should uncover some of the hidden curriculum behind how people’s research portfolios are evaluated on the job market, for tenure, for promotion, and so on.

But first, what does “successful” mean? This is where objective criteria come into play, but I can think of several proxies for success.1 First, there is success at the extensive margin: Does someone get tenure? Do they get promoted? Are they considered for endowed chairs or named professorships? Second, there is success at the intensive margin: How many Google Scholar or Web of Science citations does someone have? What is their h-index? What is their salary relative to comparable matches? And then there is stuff like the kind of job offers they get when they go on the market.

“Quantity has a quality all of its own,” a mentor once told me. By that, he was alluding to the fact that while some researchers in our discipline (i.e., agricultural economics) are known for publishing high-quality articles, others are known for publishing a high quantity of articles, and that publishing a high quantity of articles can eventually add up to quality. I wanted to talk about quantity, quality, or even both can be leveraged in terms of having a scholarly impact.