Experimental Design
Our design leverages naturally occurring, random variation in the timing of Bolsa Família (BFP) transfers to estimate the effects of short-term liquidity constraints on adolescent outcomes. BFP disburses transfers on different days each month based on the last digit of a household's randomly assigned beneficiary identification number (NIS). This staggered payment schedule allows us to compare, within each school and survey day, students whose families recently received their transfer (0–7 days ago), who we denote as the "early cycle group" with those nearing the end of their payment cycle (23–30 days since last transfer), who we refer to as the "late cycle group." We conduct student surveys in 30 public secondary schools across São Paulo, selected in collaboration with the State Secretariat of Education for their high concentration of BFP beneficiaries. By visiting schools during the middle of the monthly payment calendar, we ensure that students surveyed on the same day differ only in how recently their households received transfers. We include survey date fixed effects and pre-specified covariates to isolate the impact of liquidity availability on cognitive performance, nutrition, sleep, time use, and psychological and physical well-being.
To complement the student surveys and better understand household behavior around payday, we implement a second survey targeting the BFP recipient in each student’s household (typically the mother). These surveys allow us to estimate how household financial behavior, consumption patterns, labor supply, and coping strategies vary throughout the payment cycle.