A 1997 study by Spencer, Dupree, and Hartmann on African American adolescents serves as a practical application of the Phenomenological Variant of Ecological Systems Theory (PVEST). The research found that for both boys and girls, being unpopular with peers predicted negative attitudes toward learning. However, for boys, increased stress predicted a less negative learning attitude, which researchers hypothesized was due to a focus on the school environment rather than personal issues, alongside perceiving that teachers had positive expectations of them. Ultimately, the researchers concluded that PVEST accounted for how others' perceptions and the adolescents' subsequent attitudes were reciprocally related.