Recruitment Strategies in the European Social Survey (ESS) Round 12

This paper evaluates recruitment strategies for the European Social Survey (ESS) as it transitions to self-completion fieldwork in Norway.  We embed a recruitment experiment in the ESS Round 12 self-completion fieldwork, comparing two resource-intensive approaches: (i) promising larger conditional monetary incentives and (ii) following up nonrespondents through in-person visits by fieldworkers. In addition, we experimentally vary the timing of the conditional incentive promise (first vs. third contact attempt). The resulting

2×2×2 full factorial design enables estimation of marginal effects on response rates, sample composition (representativeness), and marginal operational costs. Preliminary results indicate sizable gains from “going hard and early”, with response rates approaching 50 percent with a strategy of promising NOK 500 in conditional incentives to all respondents already in the invitation letter. Using a 'knock-to-nudge' strategy with nonrespondents prove costly and inefficient in a Norwegian setting as a high-cost, sparsely populated  country.