Shulamit Kahn

Women in Academic Science A Changing Landscape

Much has been written in the past two decades about women in academic science careers, but this literature is contradictory. Many analyses have revealed a level playing field, with men and women faring equally, whereas other analyses have suggested numerous areas in which the playing field is not level. The only widely-agreed-upon conclusion is that women are underrepresented in college majors, graduate school programs, and the professoriate in those fields that are the most mathematically intensive, such as geoscience, engineering, economics, mathematics/computer science, and the physical sciences. In other scientific fields (psychology, life science, social science), women are found in much higher percentages. In this monograph, we undertake extensive life-course analyses comparing the trajectories of women and men in math-intensive fields with those of their counterparts in non-math-intensive fields in which women are close to parity with or even exceed the number of men. We begin by examining early-childhood differences in spatial processing and follow this through quantitative performance in middle childhood and adolescence, including high school coursework. We then focus on the transition of the sexes from high school to college major, then to graduate school, and, finally, to careers in academic science. The results of our myriad analyses reveal that early sex differences in spatial and mathematical reasoning need not stem from biological bases, that the gap between average female and male math ability is narrowing (suggesting strong environmental influences), and that sex differences in math ability at the right tail show variation over time and across nationalities, ethnicities, and other factors, indicating that the ratio of males to females at the right tail can and does change. We find that gender differences in attitudes toward and expectations about math careers and ability (controlling for actual ability) are evident by kindergarten and increase thereafter, leading to lower female propensities to major in math-intensive subjects in college but higher female propensities to major in non-math-intensive sciences, with overall science, technology, engineering, and mathematics (STEM) majors at 50% female for more than a decade. Post-college, although men with majors in math-intensive subjects have historically chosen and completed PhDs in these fields more often than women, the gap has recently narrowed by two thirds; among non-math-intensive STEM majors, women are more likely than men to go into health and other people-related occupations instead of pursuing PhDs. Importantly, of those who obtain doctorates in math-intensive fields, men and women entering the professoriate have equivalent access to tenure-track academic jobs in science, and they persist and are remunerated at comparable rates—with some caveats that we discuss. The transition from graduate programs to assistant professorships shows more pipeline leakage in the fields in which women are already very prevalent (psychology, life science, social science) than in the math-intensive fields in which they are underrepresented but in which the number of females holding assistant professorships is at least commensurate with (if not greater than) that of males. That is, invitations to interview for tenure-track positions in math-intensive fields—as well as actual employment offers—reveal that female PhD applicants fare at least as well as their male counterparts in math-intensive fields. Along these same lines, our analyses reveal that manuscript reviewing and grant funding are gender neutral: Male and female authors and principal investigators are equally likely to have their manuscripts accepted by journal editors and their grants funded, with only very occasional exceptions. There are no compelling sex differences in hours worked or average citations per publication, but there is an overall male advantage in productivity. We attempt to reconcile these results amid the disparate claims made regarding their causes, examining sex differences in citations, hours worked, and interests. We conclude by suggesting that although in the past, gender discrimination was an important cause of women’s underrepresentation in scientific academic careers, this claim has continued to be invoked after it has ceased being a valid cause of women’s underrepresentation in math-intensive fields. Consequently, current barriers to women’s full participation in mathematically intensive academic science fields are rooted in pre-college factors and the subsequent likelihood of majoring in these fields, and future research should focus on these barriers rather than misdirecting attention toward historical barriers that no longer account for women’s underrepresentation in academic science.

Women in Economics: Moving Up or Falling Off the Academic Career Ladder?

The percentage of economics doctorates awarded to women has increased over the past twenty years. This article considers whether women Ph.D. economists have increased their representation in academia, particularly at higher tenured ranks. Our study draws upon several empirical approaches and multiple data sets for the 1990s. We find that when compared with other academic disciplines, women in economics are less likely to get tenure and take longer to achieve it. Although gender differences in productivity and the effect of children on promotion partly explain womens lesser chances of receiving tenure in economics, a significant portion of the gender promotion gap remains unexplained by observable characteristics.

The effect of minimum-wage laws on the distribution of employment: theory and evidence

Abstract Recent research casts doubt on the view that minimum-wage laws reduce employment. We show that in a simple model of bilateral search with heterogeneous workers, a minimum-wage law increases employment. However, the increased competition from higher productivity workers makes lower productivity workers worse off without making higher productivity workers better off. We provide evidence that minimum-wage laws shift employment from adults to teenagers and students. This raises concerns about the distributional consequences of minimum wages even when they increase employment.

Hours Constraints and the Wage/Hours Locus

Surveys in the United States and Canada reveal that approximately half of all workers would like to work a different number of hours per week if they could continue to receive their usual hourly wage. Of these about two-thirds would like to work more hours and one-third would like to work fewer hours (Kahn and Lang, 1991; Shank, 1986). Despite the apparent prevalence of hours constraints, the reasons why they exist are poorly understood. In previous research we showed that Lazears (1981) agency model of the return to seniority is inconsistent with the data and that the specific-capital model and insurance-based implicit contract models cannot account for important regularities (Kahn and Lang, 1992, 1995). In this paper, we examine whether hours constraints can be explained by the existence of a hedonic wage/hours locus. We find that the actual wage/hours locus is reasonably consistent with the wage/hours locus predicted by observed hours constraints when the hedonic model is augmented by considerations of long-term contracting. We conclude that despite data and estimation shortcomings, hedonic choices are an important reason for hours constraints to exist.

How Important Is U.S. Location for Research in Science

This paper asks whether being located outside the United States lowers research productivity in a data set of foreign-born, U.S.-educated scientists. Instrumenting location with visa status that requires return to home countries, we find a large negative relationship between non-U.S. location and research output for countries with low income per capita but none for countries with high income per capita. This suggests that a scientist exogenously located in a country at the top of the income distribution can expect to be as productive in research as he or she would be in the United States.

Gender, Race/Ethnicity, and National Institutes of Health R01 Research Awards: Is There Evidence of a Double Bind for Women of Color?

Purpose To analyze the relationship between gender, race/ethnicity, and the probability of being awarded an R01 grant from the National Institutes of Health (NIH). Method The authors used data from the NIH Information for Management, Planning, Analysis, and Coordination grants management database for the years 2000–2006 to examine gender differences and race/ethnicity-specific gender differences in the probability of receiving an R01 Type 1 award. The authors used descriptive statistics and probit models to determine the relationship between gender, race/ethnicity, degree, investigator experience, and R01 award probability, controlling for a large set of observable characteristics. Results White women PhDs and MDs were as likely as white men to receive an R01 award. Compared with white women, Asian and black women PhDs and black women MDs were significantly less likely to receive funding. Women submitted fewer grant applications, and blacks and women who were new investigators were more likely to submit only one application between 2000 and 2006. Conclusions Differences by race/ethnicity explain the NIH funding gap for women of color, as white women have a slight advantage over men in receiving Type 1 awards. Findings of a lower submission rate for women and an increased likelihood that they will submit only one proposal are consistent with research showing that women avoid competition. Policies designed to address the racial and ethnic diversity of the biomedical workforce have the potential to improve funding outcomes for women of color.

Occupational Safety and Workers Preferences: Is There a Marginal Worker?

Occupational safety levels in nonunion firms are empirically shown to reflect only the preferences of workers with zero to three years job tenure. Therefore, ex post, the market is inefficient even if workers were optimizing at the time of hire since there are trades possible among workers that would make all workers better off. The workers who are ignored in the safety-setting process, those workers with more than three years job tenure, prefer less, not more, safety. Copyright 1987 by MIT Press.

The impact of postdoctoral training on early careers in biomedicine

While postdocs are necessary for entry into tenure-track jobs, they do not enhance salaries in other job sectors over time.

Comment on “Expectations of brilliance underlie gender distributions across academic disciplines”

Leslie et al. (Reports, 16 January 2015, p. 262) concluded that “expectations of brilliance” explained the gender makeup of academic disciplines. We reestimated their models after adding measures of disaggregated Graduate Record Examination scores by field. Our results indicated that female representation among Ph.D. recipients is associated with the field’s mathematical content and that faculty beliefs about innate ability were irrelevant.

Are recent cohorts of women with engineering bachelors less likely to stay in engineering

Women are an increasing percentage of Bachelors in Engineering (BSEs) graduates—rising from 1% in 1970 to 20% in the 2000s—encouraged by increasing K-12 emphasis on attracting girls to STEM and efforts to incorporate engineering and technology into K-12 curricula. Retention of women in STEM and in engineering in particular has been a concern historically. In this paper, we investigate whether this gap has increased because a larger proportion of females entering engineering find themselves ill-matched to this field, or whether the gap has decreased as engineering becomes more accommodating to women. Using 1993–2010 nationally representative NSF SESTAT surveys, we compare cohorts of BSEs at the same early-career stages (from 1–2 to 7–8 years post-bachelors). We find no evidence of a time trend in the gender gap in retention in engineering and a slightly decreasing gender gap in leaving the labor force. We find, as others have, that the majority of the gender retention gap is due to women leaving the labor force entirely and that this exit is highly correlated with child-bearing; yet women with engineering majors are half as likely as all college-educated women to leave the labor market. There are no clear time trends in female BSEs leaving the labor market. Single childless women are actually more likely than men to remain in engineering jobs. Some of the gender differences in retention we find are caused by differences in race and engineering subfield. With controls for these, there is no gender retention difference by 7–8 years post-bachelors for those full-time employed. There were two unusual cohorts—women with 1991–1994 BSEs were particularly likely to remain in engineering and women with 1998–2001 BSEs were particularly likely to leave engineering, compared to men. Cohorts before and after these revert toward the mean, indicating no time trend. Also, women who leave engineering are just as likely as men to stay in math-intensive STEM jobs.