John Fallon

Competitive Occupational Licensure: Doctors Versus Chiropractors

Models of occupational licensing assume one board per occupation, but many near-substitute professions are licensed by separate boards. I show that these boards compete, using medical doctors (MDs) and chiropractors (DCs) from 1907 to 1960, digitized American Medical Association records, and state-by-year variation in when chiropractic boards were adopted. After a state licensed chiropractors, its medical board became up to 15 percentage points more likely to require an internship and passed 5 percentage points fewer candidates. In the full count census, doctor prevalence fell by 16%, while chiropractor prevalence rose by 117% and chiropractors' home values by 41%. Licensing one profession changes how its substitutes are regulated.

Fewer Licenses, Similar Teachers: Changing Licensing Tests in Indiana

with Marcus A. Winters, PhD

We use longitudinal administrative data from Indiana to examine changes in teacher quality following the state's shift to a more difficult licensure test. The number of unique individuals issued an initial Indiana teaching license fell by about 22% under the new standard. Despite this substantial drop, the overall quality of incoming teachers and the relative quality of licensed teachers compared to unlicensed teachers remained largely unchanged. We find some heterogeneity by school setting, with city schools experiencing a measurable decline in teacher quality. We document a clear shift toward emergency-permit teachers following the introduction of the more difficult test. This shift may have moderated the average-quality response and concentrated effects in markets with binding teacher-supply constraints.

Extracting Value from Coworkers: Who Should Work with Whom and When?

Workers learn from their peers, but which collaborations build lasting skills? I study co-teaching, where general and special education teachers share a classroom, using administrative records on Indiana teachers, 2012–2019. I compare the same teacher before and after co-teaching. Those paired with an experienced partner (16+ years) score 0.10σ higher after returning to solo instruction; estimates for inexperienced partners are near zero. Longer collaborations add nothing. Teachers with two years of experience gain most. Schools do not exploit this: conditional on staffing, partner assignment is indistinguishable from random. Reallocating partnerships toward experienced mentors implies fiscal benefit-cost ratios of 3.6:1–7.0:1.

The Diminishing Returns to Human Recruiting in Online Labor Markets

with Emma Wiles and John Horton

Employers often rely on outside recruiters to find workers, but it is unclear whether human intermediaries add value when employers already have access to algorithmic screening tools. We study a randomized experiment in a large online labor market that assigned human recruiting assistance to employers. The recruiters increased the search and screening intensity of treated job posts: treated job posts had more recruiting and more applicant screening done on their behalf, resulting in 5% more applicants. Employers of treated job posts redirected their own screening efforts toward recruiter-sourced candidates and away from applicants who found the post on their own. Despite the increase in search intensity, treated employers were no more likely to hire than employers of control posts with access only to algorithmic tools. Match quality appears, at best, no better for the hires that resulted from the treated job posts, and treated employers were less likely to return to the platform to post a second vacancy after the experiment. We develop a model of delegated recruiting in which recruiters and employers rely on a common noisy signal; it predicts that recruiting adds value when the recruiter brings information the algorithm lacks and can subtract value when the two parties' assessments are correlated. Consistent with the model's screening mechanism, recruited applicants are positively selected on observable characteristics yet do not improve hiring outcomes. These findings suggest that as algorithmic screening improves, the scope for intermediaries to add value shrinks because it becomes harder to access independent information.

What Do Graduate Student Unions Do?

with Jesse Meredith

About 36 percent of U.S. research doctorates and 37 percent of university publications now come from universities whose graduate students bargain under a union contract, up from about 3 percent of doctorates in 1990. Using stacked event studies on the date each first contract is ratified, we find that stipends rise about 6 percent beyond local cost-of-living growth. Doctorates awarded change little for three years. Six or more years after ratification, when the first cohorts admitted under a contract reach graduation, they are about 11 percent lower. The decline is deepest in education and the humanities and smaller, though not absent, in science and engineering. Priced from the contracts themselves, the implied elasticity of doctorates with respect to their cost is 1.08, about 2.6 times the median for workers in firms. Treated universities also employ fewer ladder faculty and publish less in total. They award fewer bachelor’s degrees as well, though that decline began before the campaign. We rule out large changes in output per faculty member and in the placement and research of the remaining graduates. Across the treated universities, the decline amounts to about 2.5 percent of all U.S. research doctorates each year, so how universities absorb a contract now moves the national supply of researchers.

Federal Workforce Reductions

with Lindsey Kaler, Cameron Arnzen, Niamh Stull, and Susan Moffitt

A monthly panel of federal employment built from OPM records, comparing agencies that carried out 2025 reductions in force with those that did not, against a hand-coded measure of what Project 2025 proposed for each agency.

Firefighter Professionalization and State Capacity

with Susan Moffitt

A panel of U.S. fire departments, 1985–2017, assembled to study how the fire service professionalized.