ABSTRACT

What wider lessons can be drawn from a single impact evaluation study? This article examines how case study and source selection contribute to useful generalisation. Practical suggestions for making these decisions are drawn from a set of qualitative impact studies. Generalising about impact is a deliberative process of building, testing and refining useful theories about how change happens. To serve this goal, purposive selection can support more credible generalisation than random selection by systematically and transparently drawing upon prior knowledge of variation in actions, contexts, and outcomes to test theory against diverse, deviant and anomalous cases.

摘要

从单个影响评估研究中可以得出哪些更广泛的教训？本文研究了案例研究和来源选择如何有助于有用的概括。做出这些决定的实用建议来自一系列定性影响研究。对影响进行概括是一个构建，测试和完善关于变化如何发生的有用理论的审议过程。为了实现这一目标，有目的的选择可以通过系统地，透明地利用行为，上下文和结果的变化的先验知识来支持理论的多样性，从而对各种多样，异常和异常的情况进行测试，从而比随机选择更可靠。