What teachers are paid is usually a function of local budgets and politics — not cutting-edge research. But there’s building evidence that higher teacher pay helps encourage people to enter and stay in the classroom.

The latest study, published in the peer-reviewed American Educational Research Journal, examines interest in teaching across different countries, including the United States.

“In countries where teacher salaries are higher, 15-year-old students are more likely to expect to work as teachers,” the researchers Seong Won Han, Francesca Borgonovi, and Sonia Guerriero conclude, using data from the OECD, the group that administers the PISA exam, which tests 15-year-olds worldwide to evaluate education systems.

The relationship is strong: an increase in teacher pay by 50 percent is associated with a 75 percent increase in high schoolers’ likelihood to say they plan to go into teaching.

This comes as fewer American high school students want to become teachers, according to a 2016 analysis by the ACT, the college-entrance testing company. Policymakers may be particularly nervous about this trend in light of the decline in recent years of college students enrolling in teacher preparation programs.

A major caveat to the study, which is consistent with prior work, is that the results are correlational, meaning the study can’t prove that better salaries cause more high schoolers to become interested in teaching. Moreover, comparing educational systems across countries — with widely varying cultures and contexts — is inherently tricky. The report also shows that other factors beyond salary — like how well-respected teachers are — are related to interest in the career.

Still, the findings generally match up with research from the United States showing that teacher salary matter a great deal.

Increased pay, including through bonuses, tends to get teachers to stay in the job longer. There is less evidence on how compensation affects teacher recruitment, but what exists is generally positive. Higher pay may be particularly important for keeping math and science teachers — often areas of shortage — since they tend to be able to earn higher salaries outside teaching.

One study found that a New York City charter school that pays teachers $125,000 salaries led to notable gains in student achievement (although the analysis couldn’t show whether the hefty paychecks were the cause).

Of course, significant debate exists on whether to base pay on performance and how to distribute retirement benefits. More generally, researchers disagree on whether teachers are over or underpaid, and how exactly to determine this.

The OECD data suggests that teachers are paid substantially less than in most other countries, as a percentage of per capita GDP. A more fine-grained analysis by the Economic Policy Institute, a left-leaning think tank, found that, counting benefits and hours worked, teachers are paid about 11 percent less than similarly educated workers.

Comparisons are challenging: another recent study found that although high school teachers are underpaid, elementary and middle school teachers earn somewhat more than comparable professionals.

But asking teachers if teachers are over or underpaid may be the wrong question — as well as an impossible-to-answer one — according to some researchers. The right question, argued the University of California, Santa Barbara economist Dick Startz in a recent blog post, is, “Are we attracting and retaining enough great teachers?”

“My view,” he continued, “is that we’re getting lots of great teachers, but we’re not getting nearly as many as we need. If you agree, then you should want higher teacher salaries.”