Experimental Design
Based on the popularity score constructed from baseline measure of in-degree nominations, individuals are divided into three categories: low (L), medium (M) and high (H). Categorization is relative to the distribution of popularity score within the classroom an individual belongs to, i.e. bottom 33% of the distribution is categorized as low, top 33% as high and the remaining as medium.
The design then relies on a two-level randomization. In the lower level, individuals within the same classroom are randomly matched to each other, thus, forming pairs of the following type: LL, LM, LH, MM, MH, HH. In this case, a match to an H type desk mate is considered treatment 1, a match to an L type desk mate is considered treatment 2 and a match to an M type desk mate is considered control. A comparison of means method is employed where outcomes of individuals are compared across treatment 1 (match to H type), treatment 2 (match to L type) and control (match to M type) while controlling for baseline characteristics and classroom fixed effects. The primary population for which treatment effects are evaluated are the L type students. However, the project also tests the treatment effects on all students and also on M type and H type students separately.
In the upper level, with the focus being L type students, the proportion of LL, LM and LH type matches are varied across classrooms within the same school-grade. Three type of classrooms are created: C1 (60% (20%, 20%) of L type individuals are matched to L (M, H) type desk mates (respectively)), C2 (20% (20%, 60%) of L type individuals are matched to L (M, H) type desk mates (respectively)) and C3 (33.33% (33.33%, 33.33%) of L type individuals are matched to L (M, H) type desk mates (respectively)). For the remaining individuals in each class, pairs are formed randomly. Let's call C1 classrooms: Lopsided towards LL classroom (LopL), C2 classrooms: Lopsided towards LH classroom (LopH) and C3 classrooms: Balanced classroom (Bal).
By comparing outcomes of individuals across the three types of classroom (where one can consider LopL and LopH as treatment and Bal as control), treatment effects of classroom level changes (for e.g. better classroom management, general perception of amicability of high type peers etc.) induced by types and proportion of matches are obtained.
The lower level obtains treatment effects of the direct match whereas the upper level obtains treatment effects of overall match types. In order to further distinguish direct effects from global effects, interactions between the two treatment levels are used.
A linear in means comparison is also employed where the treatment (popularity level of desk mate) is considered to be continuous. Finally, to account for spillovers, structural assumptions are made about spillover procedure and Horvitz-Thompson estimators (Forastiere et al. 2024, Aronow and Samii 2017) are used to uncover direct vs indirect effects.
The seating plans stay in place over 2 - 2.5 working months, thus, giving desk buddies appropriate amount of time to form social connections with each other and each others' friends. Endline surveys are conducted at the termination of the seating plan.