Table S8.

Summary of results by mentor condition for years 1 and 2

Dependent variables	Significant change over time within conditions (slopes)			Comparing change over time (slopes) between conditions
	Control/no mentor	Male mentor	Female mentor	Female vs. control	Male vs. control	Female vs. male
Year 1
Belonging	Decrease	Decrease	No change	Significant	Nonsignificant	Significant
Threat/challenge ratio	Increase	Increase	No change	Significant	Nonsignificant	Nonsignificant
Engineering self-efficacy	Decrease	Decrease	No change	Significant	Nonsignificant	Nonsignificant
Thoughts of switching majors	Increase	No change	No change	Significant	Significant	Nonsignificant
Intentions to pursue advanced engineering degrees	Decrease	Decrease	No change	Significant	Significant	Nonsignificant
Year 2
Belonging	No change	Decrease	No change	Nonsignificant	Nonsignificant	Significant
Threat	Increase	Increase	Increase	Nonsignificant	Nonsignificant	Significant
Intentions to pursue advanced engineering degrees	Decrease	Decrease	No change	Significant	Nonsignificant	Nonsignificant
Retention in engineering majors, % retained	89%	82%	100%