Accurate measurement of the land rights held by individuals in customary systems as well as their impact on investment and productivity is thus essential for policy.

This paper focuses on the case of Malawi, a poor and predominantly agricultural country with widely varying institutional arrangements, to provide substantive and methodological insights on the link between individuals’ land rights and investment. To do so, we rely on two nationally representative surveys, the Malawi Integrated Household Panel Survey (IHPS) and the Fourth Integrated Household Survey (IHS4), that were conducted in parallel in 2016/17 by the Malawi National Statistical Office. Both surveys elicited parcel-level gender-disaggregated data on reported, documented, and economic ownership and on rights to bequest, sell, rent out, use as collateral, and invest in it to make improvements. The data allow us to (i) rely on within-household variation in rights for identification and (ii) to use application of organic manure and planting of cash crops as indicators for investment and diversification, to explore the extent to which such rights affect economic outcomes.

While the two surveys’ instruments are virtually identical, they adopted fundamentally different approaches to respondent selection that allow us to explore impacts of data collection methodology on substantive results. The IHPS aimed to conduct private interviews with each adult household member to elicit selfreported information regarding their personal ownership and rights for each parcel, a higher cost approach that is likely to result in higher data quality. Conversely, the IHS4 followed the traditional approach to survey data collection using proxy respondents, i.e. interview the self-identified most knowledgeable household member for each parcel to identify owners and right holders within the household. By comparing results from analysis of both data sets, we are able to draw rigorous inferences on the impact of data collection methods on survey responses and measurement of land rights. At a descriptive level, the standard practice of obtaining data on individuals’ land rights from proxy respondents -even if they profess to be knowledgeable- rather than directly from (co-)owners may under- (over)estimate the extent to which women (men) have (co-)ownership rights while exhibiting the opposite bias in terms of the type of rights female or male (co-)owners can exercise.

Regression analysis using the IHPS data as -reported by all individual parcel owners suggests that genderspecific (long-term) rights to transfer land via bequest or sale (but not (short-term) rights to make decisions on investment or production) affect investment and diversification into cash crops. Right holders’ gender matters on its own and in interaction with local norms: Female bequest and, in non-matrilineal inheritance regimes, sale rights affect investment in soil fertility (proxied by the use of organic manure) whereas male bequest rights increase the level of cash crop adoption.

These results cannot be replicated using the data from the IHS4 which allowed for proxy reporting on parcel ownership and rights. This finding materializes despite the IHS4 sample being significantly larger and 3