Leading opinion research on immigration has begun to move from size-based to change-based measures of citizens’ ethnic context. This shift is based on the theoretical assumption that over-time growth in immigrant populations is more likely to capture citizens’ attention than their current size. At present, there is no empirical evidence supporting this assumption. This article demonstrates that while the size of local immigrant populations exerts virtually no effect on perceived immigration, over-time growth strongly influences citizens’ perceptions of immigration into their community. In addition, our analyses illuminate the differential contribution of growth in local Hispanic and Asian populations to perceived immigration.

The theorization and empirical exploration of contextual effects is a long-standing feature of public opinion and political behavior research. At present, however, there is little to no evidence that citizens actually perceive the local contextual factors theorized to influence their attitudes and behaviors. In this article, we focus on two of the most prevalent contextual factors appearing in theories-racial/ethnic and economic context-to investigate whether citizens' perceptions of their local ethnic and economic contexts map onto variation in the actual ethnic composition and economic health of these environments. Using national survey data combined with Census data, and focusing on the popular topics of immigration and unemployment, we find that objective measures of the size of the immigrant population and unemployment rate in respondents' county and zip code strongly predict perceived levels of local immigration and assessments of the health of one's local job market. In addition to demonstrating that citizens are "receiving the treatment," we show that perceptions of one's context overwhelmingly mediate the effect of these objective contextual factors on relevant economic and immigration attitudes. The results from our analyses provide scholars with unprecedented evidence that a key perceptual process presumed in various contextual theories of political attitudes and behavior is, in fact, valid.

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