Experimental Design Details
The financial incentives are presented in the form of a contract that pay pays UGX 6,000 if speed never exceeds 50 kph and pays UGX 2,000 regardless of the driving behavior, daily for a total of ten days. Speed is measured through a GPS device installed in the motorbike of each study participant. Respondents are exposed to the GPS technology and provided with a mobile app to monitor their own past behavior for about one month before intervention.
The contract is the same as the one offered in the demand experiment AEARCTR-0010635: assignment to treatments is incentive-compatible with the demand experiment.
The treatment is communicated during the first in-person free-of-charge check of the GPS device, a month after its installation, at their own taxi station. All respondents are provided with a short written document about the GPS device and a token of appreciation of UGX 1,000 for each phone call completed. The incentives are explained orally. Phone calls begin before treatment. For the contract to start, the respondent must undergo the GPS check-up visit and answer the first follow-up phone call. The treatment features are reminded by the field officer during each private phone call made right before and during treatment.
1) The Flat Payment Group receives UGX 4,500 per day regardless of the driving behavior. The payment amount corresponds to the realized payment under the private incentives contract in the pilot sample. The incentives are explained privately to the respondent in the proximity to his taxi station.
2) The Private Incentive Group receives the contract outlined above privately: no other driver is informed about the offered contract, nor the willingness to pay for that contract. The incentives are explained privately to the respondent in the proximity of his taxi station.
3) The Public Incentive Group receives the same incentives offered to respondents in Group 2) except for one feature: the offer is made public to the peers working at the same taxi station. The offer corresponds to the "public excuse" offer from experiment AEARCTR-0010635: the financial incentive offer is made public, while the willingness to pay for the incentive remains private.
Incentives are made public in the following way: the field officer explains the offer to the respondent at the taxi station, in front of his peers present at that moment.
A small sub-sample is randomly assigned to the remaining treatment conditions of the demand experiment to preserve incentive compatibility and avoid any deception of the respondents.
Treatment payments are made twice: after 3 days and at the end of the contract. Information about the realized driving behavior is disclosed only to the respondent via an ad-hoc mobile app and a daily text message. The information about whether the speed exceeded 50 kph in a given day is disclosed to the respondent the following morning. No mention of payment is made in the text message or mobile app. The expected payment is discussed with the field officer during the follow-up phone calls.
Payments of the token of appreciation for completing the phone survey are sent the same day. All payments are made via mobile money.
The GPS tracker allows for measuring a set of driving behavior and labor supply outcomes, including speed, route choice, length, moving duration, number of rides, and number of customers. These measures are used jointly with survey answers from the questionnaire administered right before and during treatment. I am interested in the effect of the contracts as a function of the expected payoff from the contract, contract demand, profits, and share of recurrent customers at baseline. I will compare changes in outcome across treatment arms 1) vs 2) and 2) vs 3), controlling for outcome at baseline.