The mechanism(s) of neighbourhood effects: Theory, evidence, and policy implications

Abstract

Although there is now a large body of empirical research on neighbourhood effects, we know relatively little about the causal mechanisms responsible for relationships between neighbourhood attributes and individual outcomes. A list of 15 potential causal pathways which may lead to neighbourhood effects is given, grouped into four categories: social-interactive mechanisms, environmental mechanisms, geographical mechanisms, and institutional mechanisms. The ultimate goal of neighbourhood effects research is not only to identify which mechanisms are responsible for neighbourhood effects, but also to quantitatively ascertain their relative contributions to the outcome under investigation. A pharmacological metaphor of dosage-response is used to understand how the theoretical mechanisms could be causally linked to individual outcomes. This metaphor refers to questions regarding the composition and the administration of the neighbourhood dosage, and the neighbourhood dosage-response relationship. This chapter concludes that despite the ever growing literature on neighbourhood effects, there is far too little scholarship to make many claims about which causal links dominate for which outcomes for which people in which national contexts and any conclusions on the existence of such effects should be treated as provisional at best.