Postdocs' lab engagement predicts trajectories of PhD students' skill development.

The doctoral advisor-typically the principal investigator (PI)-is often characterized as a singular or primary mentor who guides students using a cognitive apprenticeship model. Alternatively, the "cascading mentorship" model describes the members of laboratories or research groups receiving mentorship from more senior laboratory members and providing it to more junior members (i.e., PIs mentor postdocs, postdocs mentor senior graduate students, senior students mentor junior students, etc.). Here we show that PIs' laboratory and mentoring activities do not significantly predict students' skill development trajectories, but the engagement of postdocs and senior graduate students in laboratory interactions do. We found that the cascading mentorship model accounts best for doctoral student skill development in a longitudinal study of 336 PhD students in the United States. Specifically, when postdocs and senior doctoral students actively participate in laboratory discussions, junior PhD students are over 4 times as likely to have positive skill development trajectories. Thus, postdocs disproportionately enhance the doctoral training enterprise, despite typically having no formal mentorship role. These findings also illustrate both the importance and the feasibility of identifying evidence-based practices in graduate education.

Null effects of boot camps and short-format training for PhD students in life sciences.

Many PhD programs incorporate boot camps and summer bridge programs to accelerate the development of doctoral students' research skills and acculturation into their respective disciplines. These brief, high-intensity experiences span no more than several weeks and are typically designed to expose graduate students to data analysis techniques, to develop scientific writing skills, and to better embed incoming students into the scholarly community. However, there is no previous study that directly measures the outcomes of PhD students who participate in such programs and compares them to the outcomes of students who did not participate. Likewise, no previous study has used a longitudinal design to assess these outcomes over time. Here we show that participation in such programs is not associated with detectable benefits related to skill development, socialization into the academic community, or scholarly productivity for students in our sample. Analyzing data from 294 PhD students in the life sciences from 53 US institutions, we found no statistically significant differences in outcomes between participants and nonparticipants across 115 variables. These results stand in contrast to prior studies presenting boot camps as effective interventions based on participant satisfaction and perceived value. Many universities and government agencies (e.g., National Institutes of Health and National Science Foundation) invest substantial resources in boot camp and summer bridge activities in the hopes of better supporting scientific workforce development. Our findings do not reveal any measurable benefits to students, indicating that an allocation of limited resources to alternative strategies with stronger empirical foundations warrants consideration.

Should Mom go back to school? Post-natal educational attainment and parenting practices.

Although the relationship between educational attainment and parenting practices is well documented, it is typically examined at only one point in time. What happens if mothers acquire more education after the birth of their children: do they alter their parenting practices? Panel data models based on longitudinal data from ECLS-K indicate that changes in mother's educational attainment are positively associated with increases in parental school involvement, having books in the home, and participating in non-academic family activities, but not with attitudes toward discipline. Although post-natal maternal education does not change all aspects of parenting, our findings are broadly consistent with the theory of cultural mobility and provide insights into the extent of socio-cultural mobility in contemporary American society.

Finding a Fit: Biological Science Doctoral Students' Selection of a Principal Investigator and Research Laboratory.

In the laboratory-based disciplines, selection of a principal investigator (PI) and research laboratory (lab) indelibly shapes doctoral students' experiences and educational outcomes. Framed by the theoretical concept of person-environment fit from within a socialization model, we use an inductive, qualitative approach to explore how a sample of 42 early-stage doctoral students enrolled in biological sciences programs made decisions about fitting with a PI and within a lab. Results illuminated a complex array of factors that students considered in selecting a PI, including PI relationship, mentoring style, and professional stability. Further, with regard to students' lab selection, peers and research projects played an important role. Students actively conceptualized trade-offs among various dimensions of fit. Our findings also revealed cases in which students did not secure a position in their first (or second) choice labs and had to consider their potential fit with suboptimal placements (in terms of their initial assessments). Thus, these students weighted different factors of fit against the reality of needing to secure financial support to continue in their doctoral programs. We conclude by presenting and framing implications for students, PIs, and doctoral programs, and recommend providing transparency and candor around the PI and lab selection processes.

Time-to-Credit Gender Inequities of First-Year PhD Students in the Biological Sciences.

Equitable gender representation is an important aspect of scientific workforce development to secure a sufficient number of individuals and a diversity of perspectives. Biology is the most gender equitable of all scientific fields by the marker of degree attainment, with 52.5% of PhDs awarded to women. However, equitable rates of degree completion do not translate into equitable attainment of faculty or postdoctoral positions, suggesting continued existence of gender inequalities. In a national cohort of 336 first-year PhD students in the biological sciences (i.e., microbiology, cellular biology, molecular biology, developmental biology, and genetics) from 53 research institutions, female participants logged significantly more research hours than males and were significantly more likely than males to attribute their work hours to the demands of their assigned projects over the course of the academic year. Despite this, males were 15% more likely to be listed as authors on published journal articles, indicating inequality in the ratio of time to credit. Given the cumulative advantage that accrues for students who publish early in their graduate careers and the central role that scholarly productivity plays in academic hiring decisions, these findings collectively point to a major potential source of persisting underrepresentation of women on university faculties in these fields.

Accumulating advantages over time: Family experiences and social class inequality in academic achievement.

Children from different family backgrounds enter schooling with different levels of academic skills, and those differences grow over time. What explains this growing inequality? While the social reproduction tradition has argued that family contexts are central to producing class gaps in academic achievement, recent quantitative studies have found that family experiences explain only a small portion of those inequalities. We propose that resolving this inconsistency requires developing a new measure of family experiences that captures the continuity of exposure over time and thus more closely reflects the logic of the social reproduction tradition. Results using data from the Early Childhood Longitudinal Study - Kindergarten cohort (ECLS-K) show that, consistent with previous quantitative research, time-specific measures of family experiences have little explanatory power. However, cumulative family experiences account for most of the growing inequality in academic achievement between children from different social class backgrounds over time. These findings support claims from the social reproduction tradition, and contribute more broadly to the understanding of how family experiences contribute to social inequality.