Upfront Unconditional Monetary Incentives in Survey Nonresponse Reduction
Observational StudyReview
High nonresponse rates threaten the internal validity of empirical field studies by introducing nonresponse bias, particularly among wealthy individuals for whom standard post-completion survey monetary rewards offer minimal relative motivation.
Picture this
Enclosing a physical cash bill inside an initial survey envelope establishes an immediate psychological gesture of trust and reciprocity. This upfront gift motivates individuals to complete and return the survey far more effectively than offering a larger financial reward that is paid only after the completed survey is mailed back.
What the evidence says
The upfront $10 cash incentive produced a 23% response rate compared to 16% for the conditional $50 check alone (t-statistic = 1.81, p-value = 0.08), helping raise the study's overall response rate to 46% across mailings.
- Who was studied
- Subsample of N = 594 initial nonresponding Massachusetts lottery players (297 winners, 297 nonwinners) re-contacted via Federal Express.
- How
- Randomized field trial comparing an unconditional upfront $10 cash enclosure combined with a $40 conditional post-completion check versus a single $50 conditional post-completion check.
What to do
1. Include small unconditional upfront cash payments in survey mailings rather than relying solely on larger conditional post-completion financial promises when sampling hard-to-reach populations.
From the source
"Consistent with Philipson's (1997) findings, the incentive scheme with $10 up front and a promise of $40 more rather than a promise of $50 did lead to a higher response rate (23 versus 16 percent)."
Estimating_the_Effect_of_Unearned_Income_on_Labor_Earnings,_Savings.pdf