Table 2. Panel B. Regressions Predicting Participants’ Likelihood of Working out Each Week during the Intervention Period.
This table reports a series of ordinary least squares regressions predicting a study participant’s weekly likelihood of completing a (a) workout anytime, (b) workout initiated during their workout window, and (c) workout initiated outside of their workout window during the four-week intervention period. In each column, we report the mean weekly fraction of participants in the control group who completed a workout within this period. The primary predictors included in these regressions are treatment status indicators, which indicate the size of the incentive offered for exercise ($3 versus $7) and the flexibility of the workout schedule (flexible versus routine). We report pairwise Wald tests to assess whether or not all paired regression coefficients reported differ significantly from each other.
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | |
|---|---|---|---|---|---|---|---|---|---|
| Any Workouts? (Y/N) | Any In-Window Workouts? (Y/N) | Any Out-of-Window Workouts? (Y/N) | Any Workouts? (Y/N) | Any In-Window Workouts? (Y/N) | Any Out-of-Window Workouts? (Y/N) | Any Workouts? (Y/N) | Any In-Window Workouts? (Y/N) | Any Out-of-Window Workouts? (Y/N) | |
| Flexible Payment $3 | 0.15*** (0.04) | 0.13*** (0.04) | 0.12*** (0.04) | ||||||
| Flexible Payment $7 | 0.23*** (0.04) | 0.17*** (0.04) | 0.20*** (0.04) | ||||||
| Routine Payment $3 | 0.13** (0.04) | 0.20*** (0.04) | −0.04 (0.04) | ||||||
| Routine Payment $7 | 0.17*** (0.04) | 0.30*** (0.04) | −0.07* (0.04) | ||||||
| $3 Interventions | 0.14*** (0.04) | 0.17*** (0.03) | 0.04 (0.04) | ||||||
| $7 Interventions | 0.20*** (0.04) | 0.23*** (0.03) | 0.06+ (0.04) | ||||||
| Flexible Interventions | 0.19*** (0.04) | 0.15*** (0.03) | 0.16*** (0.04) | ||||||
| Routine Interventions | 0.15*** (0.04) | 0.25*** (0.03) | −0.06 (0.03) | ||||||
|
| |||||||||
| Mean Values of Control Group | 0.50 | 0.31 | 0.32 | 0.50 | 0.31 | 0.32 | 0.50 | 0.31 | 0.32 |
| Observations | 10032 | 10032 | 10032 | 10032 | 10032 | 10032 | 10032 | 10032 | 10032 |
| R-squared | 0.05 | 0.06 | 0.08 | 0.05 | 0.05 | 0.03 | 0.05 | 0.05 | 0.08 |
|
| |||||||||
| Wald Test ($3 Flexible-$7 Flexible) | |||||||||
| Difference in Coefficients | −0.07** (0.02) | −0.04 (0.02) | −0.07** (0.02) | ||||||
| Wald Test ($3 Flexible-$3 Routine) | |||||||||
| Difference in Coefficients | 0.03 (0.02) | −0.07** (0.03) | 0.16*** (0.02) | ||||||
| Wald Test ($3 Flexible-$7 Routine) | |||||||||
| Difference in Coefficients | −0.02 (0.02) | −0.17*** (0.02) | 0.20*** (0.02) | ||||||
| Wald Test ($7 Flexible-$3 Routine) | |||||||||
| Difference in Coefficients | 0.10*** (0.02) | −0.03 (0.03) | 0.24*** (0.02) | ||||||
| Wald Test ($7 Flexible-$7 Routine) | |||||||||
| Difference in Coefficients | 0.05* (0.02) | −0.13*** (0.02) | 0.27*** (0.02) | ||||||
| Wald Test ($3 Routine-$7 Routine) | |||||||||
| Difference in Coefficients | −0.04+ (0.02) | −0.09*** (0.03) | 0.03+ (0.02) | ||||||
| Wald Test ($3-$7) | |||||||||
| Difference in Coefficients | −0.06*** (0.02) | −0.07*** (0.02) | −0.02 (0.02) | ||||||
| Wald Test (Flexible-Routine) | |||||||||
| Difference in Coefficients | 0.04* (0.02) | −0.10*** (0.02) | 0.22*** (0.02) | ||||||
Note: Standard errors clustered by workout buddy pair are in parentheses.
p<0.10
p<0.05
p<0.01
p<0.001.
The control variables in the regressions are indicators for randomization strata (12 strata: three randomization dates, crossed with whether or not workout window perfectly overlapped with partner’s workout window, crossed with whether or not self-reported pair number of workouts per week was above median for randomization date), as well as an indicator for missing workout window.