Nan Zhang, Alexandra Kommol
Ethnic diversity and cooperation: evidence from a lost letter experiment

Journal of Ethnic and Migration Studies, In Press: (publ. online before print)
ISSN: 1369-183X (print), 1469-9451 (online)

Are residents of ethnically diverse communities less likely to encounter acts of cooperation and kindness from strangers? Although a vast literature has arisen examining the relationship between ethnic diversity and popular attitudes such as social trust, we know little about how prosocial behaviors vary across neighborhoods. This study presents evidence from a ‘lost letter’ experiment conducted across 77 neighborhoods in 13 German cities. We experimentally vary the ethnic identity of letter senders and recipients, and also carefully select our experimental field sites to create ‘matched sets’ of neighborhoods that differ only with respect to the percentage of foreign residents. We find no difference in return rates across our ethnicity treatments, and no overall relationship between return rates and neighborhood diversity. However, comparing across ‘matched sets,’ we do detect significantly lower return rates in areas featuring higher unemployment. Taken together, our findings support the view that it is not diversity per se, but rather associated socioeconomic deprivation, which is most detrimental to cooperative neighborhood interactions.