'No words'-Machine-learning classified nonverbal immediacy and its role in connecting teacher self-efficacy with perceived teaching and student interest.

Background: Much is known about the positive effects of teachers' self-efficacy on instruction and student outcomes, but the processes underlying these relations are unknown.

Aims: We aimed to examine the effects of teacher self-efficacy for student engagement (TSESE) before a lesson on teachers' nonverbal immediacy (NVI) and their enthusiastic teaching. Furthermore, we examined how NVI and enthusiastic teaching affected students' interest after the lesson, controlling for prior interest.

Sample: We used data from the German TALIS video study in the context of the international TALIS study. The study included 50 teachers (46% women) and their 1140 students (53% girls; ageM = 15 years).

Methods: We developed a computational model to assess teachers' NVI on classroom video data. Using a multimodal longitudinal approach, we tested sequential processes with multilevel path models.

Results: TSESE before the lesson (Time 1) was positively and significantly related to teachers' NVI during the lesson (Time 2). Teachers' NVI (Time 2) was positively related to class-level enthusiastic teaching behaviours, reported after the lesson (Time 3). Student-reported enthusiastic teaching behaviours (Time 3) were significantly and positively associated with students' interest (Time 3) when controlling for students' prior interest (Time 1). Students' interest after the lesson (Time 3) was significantly and positively related to students' interest 6 weeks later (Time 4).

Conclusions: Nonverbal behaviours of the teacher are central to classroom instruction by promoting students' perceptions of the teachers' enthusiastic teaching behaviours.