THE PROTECTION OF POOR HOUSEHOLDS in high-risk agrarian economies from shocks to their incomes has often been seen as a compelling motive for various forms of policy intervention including transfers of cash or food, credit subsidies, and public employment schemes (for a survey see Lipton and Ravallion (1995)). The desirability of such safety net policies clearly depends on how well pre-existing risk-sharing arrangements work. While it is commonly thought that, without effective policy intervention, rural households are vulnerable to village-wide shocks such as adverse prices or poor rains, it is less clear to what extent risk-sharing institutions within the village mitigate the effects of idiosyncratic income risk stemming, for instance, from ill-health or localized crop damage.2 Several recent papers have used household-level data to implement tests of risk-sharing that might inform such concerns.3 These tests are based on the proposition that with perfect risk-sharing, consumption at the household level should be insured against idiosyncratic risks and thus depend solely on the realization of the aggregate risk (Wilson (1968); Diamond (1967)). Townsend (1994) tests this implication of perfect intra-village risk-sharing using longitudinal household data on consumptions and incomes for three villages in India. He reports that the full-insurance hypothesis provides a surprisingly good benchmark in that household consumptions co-move and do not appear to be much influenced by contemporaneous own income. Our aim here is to examine the robustness of this potentially important finding. We have two main concerns. The first is that the specification Townsend adopts potentially biases his test towards the null hypothesis of full insurance because it yields inconsistent estimates of the key test parameter under a plausible alternative. We therefore estimate a different specification that generates consistent estimates under both the null and the alternative. Our second concern is that a particular form of measurement error in the consumption data Townsend uses may have further biased his results toward the null hypothesis of full-insurance. To address this concern, we use an instrumental variables procedure when we implement the test of consumption insurance with Townsend's consumption data. We also re-estimate the test equations with a measure of consumption derived from the same underlying primary data by an alternate method. Finally, Townsend reports 1Discussions with Robert Townsend stimulated our interest in this investigation. The staff of the
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