Integration through crossing circles natives' opportunity pools and diversification of friendships in a transforming Europe.

The article studies the social relationships of natives in the destination countries of migrants. Specifically, the article estimates the share of non-natives in natives' friendship opportunity pools (FOP) and its correlation with natives only having native friends. Danish data is used due to a unique possibility of linking register information, allowing the establishment of an objective measurement of FOP at various levels, and survey information, allowing the measurement of natives' friendship composition, at the individual level. In our sample, 55 per cent of the natives have a migrant friend, and it is found to be strongly correlated with FOP. In line with Blau's macro-sociological framework and assimilation theory, we thereby find support for a transformation of the 'weak' friendship ties of natives in destination countries. The FOP effects are found to be stronger for older respondents and those with negative attitudes toward immigration. The effects are found across measurement at the neighbourhood-, parish – and municipal level and after control for general attitudes toward immigration. In models with three levels simultaneously included, the effects are present at the neighbourhood and municipal level, but absent at the parish level. [ABSTRACT FROM AUTHOR]