Rural electrification rollout sequencing and women's off-farm enterprise entry in Tanzania: a difference-in-differences analysis of grid-extension thresholds

Rural electrification programmes in Tanzania have expanded the grid unevenly, and the sequencing of connections may shape whether women enter off-farm enterprises. Because no household panel data are analysed here, the paper is a methodological and conceptual contribution: it specifies the estimand, the treatment definition, the parallel-trends assumption, and the threats to identification that arise when rollout is sequenced by administrative thresholds. The design is illustrated with the DHS Program indicator 'Age difference between man and woman is 10+ years' (id MA_ADIF_W_O10), drawn from 135 country-survey observations across 36 African countries between 1994 and 2025, with a mean of 32.358 and a standard deviation of 15.598. That indicator is used only to characterise the survey infrastructure on which the design would rely, not to estimate the effect of electrification. Threshold-based sequencing generates credible counterfactuals only when the threshold rule is explicit, the running variable is measured without manipulation, and the enterprise-entry outcome is observed before and after connection. The contribution is a design template for evaluating rollout sequencing, together with a specification of the conditions under which difference-in-differences estimates of electrification effects on women's enterprise entry can be interpreted causally.