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. 2022 Mar 31;17(3):e0265074. doi: 10.1371/journal.pone.0265074

Table 4. Negative binomial regressions examining predictors of presentations with undergraduate (UG) authors (left estimates) and presentations with UG first authors (right estimates).

# Publications with UGs # Publications with UGs as First Author
No Controls Controlling for PUI status and Productivity No Controls Controlling for PUI status and Productivity
Variable Standardized IRR [CI95%]1 Standardized IRR [CI95%]1 Standardized IRR [CI95%]1 Standardized IRR [CI95%]1 Interpretation
Institution
PUI v Grad-Serving2 1.49 [1.11, 2.00] 1.45 [1.06, 1.98] 1.54 [1.12, 2.12] 1.58 [1.13, 2.21] Grad serving institutions: 45% more presentations with UGS as authors; 58% more presentations with UGs as first author
University Rank Within Type .97 [.81, 1.17] .90 [.74, 1.10] .93 [.77, 1.13] .88 [.72, 1.09]
Endowment .85 [.71, 1.03] .82 [.67, 1.00] .68 [.53, .87] .67 [.52, .86] 1 SD increase in endowment: 33% fewer presentations with UGs as first author
Acceptance Rate3 1.18 [.98, 1.41] 1.16 [.96, 1.40] 1.40 [1.15, 1.72] 1.36 [1.10, 1.67] 1 SD increase in acceptance rate: 36% fewer presentations with UGs as first author
Student-Faculty Ratio 1.17 [.97, 1.40] 1.07 [.85, 1.35] 1.21 [.99, 1.47] 1.09 [.86, 1.39]
Institutional Support for UG Research 1.00 [.87, 1.16] 1.06 [.91, 1.23] 1.05 [.90, 1.22] 1.11 [.94, 1.31]
Department
# of Faculty 1.12 [.96, 1.31] 1.03 [.88, 1.21] 1.08 [.91, 1.28] .93 [.77, 1.13]
UG Research in Curriculum .99 [.86, 1.15] 1.08 [.92, 1.28] 1.06 [.91, 1.25] 1.13 [.95, 1.35]
UG Research in Course Load .96 [.71, 1.29] 1.06 [.77, 1.44] 1.19 [.87, 1.64] 1.24 [.89, 1.74]
Course Load 1.02 [.87, 1.20] 1.06 [.89, 1.27] 1.13 [.95, 1.34] 1.15 [.95, 1.39]
Faculty Characteristics
Age .98 [.85, 1.12] 1.00 [.86, 1.17] 1.00 [.86, 1.16] 1.07 [.91, 1.26]
Female v. Male 1.06 [.77, 1.45] 1.11 [.79, 1.56] 1.09 [.78, 1.53] 1.19 [.83, 1.69]
Years as a Full-Time Faculty member .97 [.84, 1.12] 1.00 [.85, 1.18] .96 [.82, 1.12] 1.06 [.89, 1.27]
Tenure Track Rank .94 [.77, 1.14] .97 [.78, 1.19] .90 [.73, 1.10] 1.00 [.81, 1.25]
Grant Recipient (> $5k) 1.26 [.93, 1.72] 1.17 [.82, 1.68] 1.05 [.76, 1.46] 1.09 [.74, 1.60]
# of Publications 1.10 [.91, 1.31] 1.05 [.87, 1.26] 1.02 [.83, 1.24] .96 [.78, 1.18]
Hours Worked Per Week 1.02 [.89, 1.18] .98 [.85, 1.14] 1.03 [.88, 1.21] 1.02 [.86, 1.21]
Hours Spent on Research 1.23 [1.06, 1.42] 1.21 [1.00, 1.46] 1.18 [1.00, 1.38] 1.21 [.99, 1.49] 1 SD increase in hours spent on research each week: 21% more presentations with UGs annually.
Hours Spent Teaching Per Course .90 [.78, 1.04] .92 [.79, 1.07] .88 [.75, 1.04] .91 [.77, 1.08]
Satisfaction with Current Position .96 [.83, 1.11] .96 [.83, 1.12] .98 [.84, 1.14] .98 [.83, 1.15]
Research Lab
# Grad Students in Lab4 1.18 [.95, 1.47] 1.17 [.93, 1.48] 1.13 [.91, 1.40] 1.17 [.92, 1.49]
# Undergrads in Lab 1.43 [1.19, 1.71] 1.36 [1.13, 1.63] 1.58 [1.29, 1.93] 1.53 [1.24, 1.87] 1 SD increase in number of undergraduates in the labs: 36% more presentations with UGs, 53% more presentations with UGs as first author annually.
Experience with Diverse Students 1.23 [1.05, 1.43] 1.19 [1.01, 1.40] 1.18 [1.00, 1.40] 1.17 [.98, 1.40]
Collaboration
% of RAs Who Are Juniors or Seniors .93 [.79, 1.09] .93 [.78, 1.11] .99 [.83, 1.18] .90 [.75, 1.09]
% of RAs Who Are Primarily "Assistants" .92 [.79, 1.07] .91 [.77, 1.07] .85 [.72, .99] .78 [.66, .93] 1 SD increase in % of undergraduates in the lab who are “assistants”: 22% fewer presentation with UGs as first author annually.
% of RAs Who Are Primarily "Collaborators" 1.20 [1.03, 1.40] 1.22 [1.04, 1.43] 1.29 [1.09, 1.51] 1.37 [1.15, 1.63] 1 SD increase in % of undergraduates in the lab who are “collaborators”: 22% more presentations with UGs, 37% more presentations with UGs as first author annually.
Length of Collaboration with Undergrads 1.16 [1.00, 1.33] 1.13 [.98, 1.32] 1.18 [1.02, 1.36] 1.16 [1.00, 1.35]
Collaborations with other Faculty
Primarily Students (No Outside Faculty) 1.02 [.88, 1.19] 1.01 [.86, 1.19] 1.12 [.95, 1.31] 1.09 [.92, 1.30]
Within Department 1.06 [.91, 1.23] 1.02 [.87, 1.19] 1.06 [.91, 1.25] 1.03 [.87, 1.22]
Outside Dept, Within Univ. 1.15 [1.00, 1.33] 1.13 [.97, 1.31] 1.13 [.97, 1.32] 1.09 [.92, 1.28]
Outside the University 1.16 [.99, 1.36] 1.16 [.99, 1.36] 1.10 [.93, 1.30] 1.12 [.94, 1.33]
Collaborations with Students
Primarily Work Alone on Projects (No Students) .79 [.67, .93] .79 [.66, .93] .77 [.65, .92] .77 [.64, .93] 1 SD increase in endorsement that a faculty member works alone: 21% fewer presentations with UGs, 23% fewer presentations with UGs as first author annually.
Primarily Undergraduate Lab 1.05 [.91, 1.22] 1.19 [1.00, 1.41] 1.24 [1.06, 1.45] 1.39 [1.16, 1.68] 1 SD increase in endorsement that lab is primarily a UG lab: 39% more presentations with UGs as first author annually.
Both Grad and Undergrad Co-Investigators4 1.22 [.99, 1.52] 1.24 [.98, 1.56] 1.08 [.86, 1.35] 1.13 [.89, 1.45]
Primarily Grad, Expected Mentoring of UG4 1.14 [.92, 1.42] 1.17 [.93, 1.47] 1.02 [.82, 1.27] 1.05 [.83, 1.34]
PI Supervises Grad Who Supervises UG4 1.08 [.87, 1.33] 1.10 [.87, 1.39] .98 [.79, 1.23] .98 [.77, 1.26]
Faculty-Student Interaction Styles
Collegial Relationships with UGs 1.20 [1.03, 1.40] 1.24 [1.06, 1.46] 1.41 [1.19, 1.67] 1.44 [1.21, 1.73] 1 SD increase in collegiality with UGs: 24% more presentations with UGs, 44% more presentations with UGs as first author annually.
UGs Impact Project Direction 1.16 [1.00, 1.35] 1.17 [1.01, 1.37] 1.33 [1.13, 1.56] 1.31 [1.11, 1.55] 1 SD increase in allowing UGs to impact project direction: 17% more presentations with UGs, 31% more presentations with UGs as first author annually.
Very Accessible to UGs 1.01 [.87, 1.16] 1.05 [.90, 1.22] 1.12 [.96, 1.31] 1.13 [.96, 1.34]
Clear Expectations for UGs 1.13 [.97, 1.31] 1.15 [.98, 1.35] 1.19 [1.02, 1.39] 1.24 [1.05, 1.47] 1 SD increase in setting clear expectations for UGs: 24% more presentations with UGs as first author annually.
Project Characteristics
Original Projects (vs. Replications) 1.15 [.99, 1.32] 1.13 [.97, 1.31] 1.07 [.92, 1.25] 1.12 [.96, 1.32]
Number of Projects Per Year 1.42 [1.21, 1.67] 1.38 [1.16, 1.63] 1.52 [1.28, 1.80] 1.51 [1.26, 1.80] 1 SD increase in # of projects annually: 38% more presentations with UGs, 51% more presentations with UGs as first author annually.
Study Length 1.12 [.97, 1.28] 1.09 [.94, 1.27] 1.10 [.95, 1.27] 1.06 [.91, 1.24]
Participants
Animals v. Humans5 .91 [.47, 1.74] .91 [.47, 1.74] .87 [.43, 1.77] .87 [.43, 1.77]
Adults v. Children5 .91 [.54, 1.53] .91 [.54, 1.53] .72 [.41, 1.28] .72 [.41, 1.28]
Average # of Participants 1.04 [.91, 1.20] 1.06 [.92, 1.23] 1.10 [.93, 1.30] 1.05 [.89, 1.24]
Primary Data Collection
Online 1.19 [.86, 1.63] 1.25 [.89, 1.76] 1.37 [.97, 1.94] 1.31 [.91, 1.89]
Individuals in Person 1.36 [.98, 1.87] 1.32 [.95, 1.85] 1.37 [.97, 1.94] 1.35 [.94, 1.94]
Groups in Person .96 [.70, 1.32] .99 [.71, 1.38] .96 [.69, 1.36] 1.02 [.71, 1.46]
Faculty Perceptions of Students & Research
Student Quality 1.28 [1.10, 1.48] 1.28 [1.10, 1.51] 1.32 [1.12, 1.55] 1.35 [1.14, 1.60] 1 SD increase in perceived student quality: 28% more presentations with UGs, 35% more presentations with UGs as first author annually.
Benefit (vs. Cost) of Research 1.13 [.98, 1.30] 1.12 [.96, 1.31] 1.15 [.99, 1.34] 1.19 [1.01, 1.40] 1 SD increase in perceiving UG research as having more benefits than costs: 19% more presentations with UGs as first author annually.
Enjoyment of Mentoring UGs 1.34 [1.14, 1.57] 1.34 [1.12, 1.59] 1.41 [1.17, 1.68] 1.42 [1.18, 1.72] 1 SD increase in enjoyment of UG mentoring: 34% more presentations with UGs, 42% more presentations with UGs as first author annually.
Perceived Benefit to UG of conducting/presenting/publishing research (3-item index) 1.25 [1.06, 1.48] 1.26 [1.06, 1.49] 1.33 [1.11, 1.60] 1.30 [1.08, 1.57] 1 SD increase in perceived benefit of research to students: 26% more presentations with UGs, 30% more presentations with UGs as first author annually.

Notes

Bolded estimates indicate p < .05.

1 = IRR is incidence rate ratio, or the % of change in the DV one would expect between each unit of change in the predictor. IRRs of 1.00 indicate no change, IRRs above 1.00 indicate a positive relationship whereas IRRs below 1.00 indicate a negative relationship. The IRRs are standardized in that they are expressed in terms of change in the outcome per 1SD change in the predictor for polytomous and continuous variables. Dichotomous variables are coded as -.5, .5 so the outcomes are expressed as the difference between the two categories.

2 = The columns that control for PUI status and overall productivity only control for one of these variables when the other is the focal indicator.

3 = Higher scores indicate less selectivity.

4 = Graduate-serving institutions only.

5 = Appear in same model; entering both of these comparisons into a model simultaneously creates a comparison between animal researchers and human researchers and a contrast between researchers studying adults and children (ignoring animal researchers).