A new perspective on the issue of selection bias into randomized controlled field experiments

Michele Belot, Jonathan James

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2 Citations (Scopus)
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Abstract

Many randomized controlled trials require participants to opt in. Such self-selection could introduce a potential bias, because only the most optimistic may participate. We revisit this prediction. We argue that in many situations, the experimental intervention is competing with alternative interventions participants could conduct themselves outside the experiment. Since participants have a chance of being assigned to the control group, participating has a direct opportunity cost, which is likely to be higher for optimists. We propose a model of self-selection and show that both pessimists and optimists may opt out of the experiment, leading to an ambiguous selection bias.
Original languageEnglish
Pages (from-to)326-328
JournalEconomics Letters
Volume124
Issue number3
Early online date13 Jun 2014
DOIs
Publication statusPublished - Sep 2014

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Self-selection
Selection bias
Experiment
Field experiment
Opportunity cost
Prediction
Randomized controlled trial

Keywords

  • Field experiments
  • Selection bias

Cite this

A new perspective on the issue of selection bias into randomized controlled field experiments. / Belot, Michele; James, Jonathan.

In: Economics Letters, Vol. 124, No. 3, 09.2014, p. 326-328.

Research output: Contribution to journalArticle

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