Piece-Rate Incentive Effect vs. Worker Selection
RCTReview
Employers paying piece rates often cannot separate whether higher output is driven by increased worker effort or by attracting higher-ability workers. Uncoupling these two mechanisms is essential for optimal contract design in developing country labor markets.
Picture this
Think of a commission system where salespeople receive pay for each item sold. Higher earnings could motivate existing salespeople to work faster, or they could attract top salespeople from competing firms. By using a lottery-like wage mechanism that breaks the link between a worker's requested minimum wage and their actual pay rate, the framework isolates pure individual effort from the selection of who gets hired.
What the evidence says
Raising the piece rate by 10 MWK increases output quantity by 0.18 to 0.26 units sorted per day from a baseline mean of 7.35 units (p < 0.01), establishing a positive incentive effect. Controlling for actual piece rate received, reservation wage (minimum willingness to accept) exhibits a slightly negative or zero relationship with output quantity (a 10 MWK increase in minimum WTA lowers daily output by 0.20 to 0.30 units in random effects models, p < 0.05).
- Who was studied
- N = 689 rural Malawian participants across 1,875 daily observations (66.5% female, mean age 34.9 years).
- How
- Randomized field experiment using a simplified Becker-DeGroot-Marschak (BDM) mechanism across 12 villages during high and low labor demand seasons.
What to do
Implement a two-stage randomized wage mechanism during piece-rate setting to separately evaluate worker effort responses from reservation wage self-selection.
From the source
"We find a positive relationship between output quantity and the piece rate, and show that this is solely the result of the incentive effect, not selection."
Productivity in piece-rate labor markets: Evidence from rural Malawi