Foreign-language effects in cross-cultural behavioural research: Evidence from the Tanzanian Hadza

Abstract

Behavioural research in traditional subsistence populations is often conducted in a non-native language. Recent studies show that non-native language-use systematically influences behaviour, including in widely-used methodologies. However, such studies are largely conducted in rich, industrialised societies, using at least one European language. This study expands sample diversity. We presented four standard tasks ― a ‘dictator’ game, two sacrificial dilemmas, a wager task and five Likert- risk tolerance measures ― to 129 Hadza participants. We randomly varied study languages ― Hadzane and Kiswahili ― between participants. We report a moderate impact of study language on wager decisions, alongside a substantial effect on dilemma decisions and responses to Likert-assessments of risk. As expected, non-native languages fostered utilitarian choices in sacrificial dilemmas. Unlike previous studies, non-native-language-use decreased risk preference in wager and Likert-tasks. We consider alternative explanatory mechanisms to account for this reversal, including linguistic relativity and cultural context. Given the strength of the effects reported here, we recommend, where possible, that future cross-cultural research should be conducted in participants’ first language.