The Credibility Revolution advances quantitative research designs intended to identify causal effects from observed data. The ensuing emphasis on internal validity however has enabled the neglect of construct and external validity. This article develops a framework we call causal specification....

Social capital is currently one of social structure‘s most prominent and debated manifestations. However, we have a limited understanding of how social ties as the basis of social capital form in the first place. From one perspective social capital is viewed as: "investment in social relations...