External validity in experimental methods: a social reality check

The relevance of experimental games as methods in development research depends crucially on how far the results from the games can be extrapolated to real life, ie the external validity of those results. The extent to which external validity matters depends on what you want to do with the data, some kinds of theory testing can arguably afford indifference, but many experiments are used as an indicator of behaviour in everyday life. This paper is focused on the 15 cross-cultural studies of Henrich et al (2004) as the most systematic attempt by anthropologists to use experimental games in developing countries, to assess the extent to which such methods can illuminate norms and social preferences in reality.