In Taraba, due to the unavailability of a complete list of villages in each local government, we could not conduct a standard random sampling of villages in each selected local government and thus adopted the following approach: We obtained a list of farmers who had participated in the voucher program from the IFDC office in Abuja. For the 10 randomly selected LGAs, we compiled a list of villages in which there was at least one voucher program participant. From this list, we randomly selected two to three villages per LGA. The field staffs administering the surveys were instructed to interview five households, randomly selected from each of these villages resulting in 10-15 of the minimum of 25 households per LGA minimum to be surveyed. Field staff were also instructed to visit two to three additional villages in close proximity to these assigned villages and to interview five households in each if and only if the village head or local leaders consulted had no knowledge about the voucher program. This strategy was adopted to provide a set of control villages within an LGA which were at least in location, similar to the villages in the LGA which contained voucher program participants.

Unlike Taraba, there was no comprehensive list of the voucher program participants in and so the following strategy was employed to select survey respondents: A list of villages in Kano was compiled based on information supplied by LGAs and the Kano Agricultural Development Agency. Eighty villages were then randomly selected from this list. The field staff in Kano interviewed in pairs, with each pair interviewing eight households in about eight villages6. Households within each village were randomly selected but with due consideration that at least one out of the four households interviewed participated in the voucher program. In both states, enumerators were trained extensively in randomly selecting households in a village and how to be mindful in considering the entire village in their selection of those households to interview. Survey coordinators paid surprise field visits to some enumerators to ensure that training instructions were adhered to. Table 1 shows the distribution of surveyed households across the selected LGAs in each state.

Table 1: Distribution of survey households across local government areas in Kano and Taraba Kano Taraba Local Number of Local Government Number of Government Area households surveyed Area households surveyed 64 Sardauna 55 64 Gassol 59 60 Ussa 25 Dala 82 Kurmi 25 37 Ardo Kola 25 Ungoggo 91 Jalingo 36 83 Donga 35 60 Karim Lamido 50 49 Lau 25 Kura 50 Yorro 25 Total 640 360 Source: Generated from the fertilizer voucher program evaluation survey

6 Eight households in eight villages gives us about 64 households per pair. With 10 pairs of field staff, this gives us our 640 households in .

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