Skip to main content

Table 1 List and description of variables used in regression models

From: IITA’s genebank, cowpea diversity on farms, and farmers’ welfare in Nigeria

Variable Definition
Dependent variables
 \(d^{r}\) Menhinick richness index for cowpea varieties grown
 \(d^{e}\) Shannon evenness index for cowpea varieties grown
 \(d^{d}\) Berger-Parker dominance index for cowpea varieties grown
 \(d^{c}\) Herfindahl–Hirschman concentration index for cowpea varieties grown
 Anc = 1 if the cowpea variety grown has a genebank ancestor and 0 otherwise
 Yield Cowpea yield in kilograms (kg/ha)
 Consumption Quantity of cowpea used for home food consumption, in kilograms (kg)
 Sale Quantity of cowpea grain sold, in kilograms (kg)
Independent variables
 Household characteristics
  Age Age of the household head in years
  Sex = 1 if the household head is male and 0 otherwise
  Education Education of the household head in years
  Household size Number of household members
  Experience = 1 if the household has experience growing an improved cowpea variety and 0 otherwise
  Need credit = 1 if the household head needs credit and 0 otherwise
 Pedigree information
  Anc = 1 if the cowpea variety grown has a genebank ancestor and 0 otherwise
  NumAnc The number of genebank ancestors in the pedigree of the cowpea variety grown
 Farm characteristics
  Size Farm size in ha, using GPS
  Slope Number of plots that are perceived as flat
  Soil fertility Number of plots that are perceived as poor
  Distance to field Distance to field from residence, in minutes
 Market characteristics
  Distance to seed dealer Distance to the nearest seed dealer in minutes
  Distance to village market Distance to the village (local) market in minutes
  Distance to district market Distance to the district (main) market in minutes
 Geographical zone
  North East = 1 if the household falls within the North East zone and 0 for the North West zone