An Economic Assessment of Banana Genetic Improvement and ...

MODEL OF POTENTIAL DEMAND FOR CULTIVARS IN UGANDA 79
Table 6.1 Summary statistics for variables defined at the household level
Variable Definition Mean
Standard
deviation
Explanatory variables
Experience Ratio of years of experience to age of person in charge of banana production 0.22 0.04
Education Years of schooling of the person in charge of banana production 5.54 0.72
Dependency ratio Ratio of household dependents (aged 1–15 and older than 55 years) to total
household size 0.47 0.05
Household size Total number of household members 5.55 0.50
Extension Number of visits by extension agents in the last 6 months 0.69 0.42
Assets Value of livestock owned by the household (ten thousand Ush) 43.68 19.40
Exogenous income Exogenous income the household has received in the previous year
(ten thousand Ush) 122.73 60.46
Banana area Area allocated to banana production (acres) 0.92 0.28
Planting material Number of distinct banana cultivars available in the village 23.69 1.15
Elevation Elevation (1 = below 1,400 m.a.s.l.; 0 = above 1,400 m.a.s.l.) 0.89 0.06
Time Hours to nearest market for bananas 1.07 0.13
Notes: The mean is calculated as a weighted average for each variable. m.a.s.l. is meters above sea level.
nation of scientists’ and farmers’ criteria.
NARO scientists have identified several cultivars
for initial transformation assays to
represent the range of genomic and usegroup
diversity found among clone sets in
Uganda (Karamura and Pickersgill 1999). 4
Survey data reveal the cultivars that are
currently most frequently and extensively
grown by farmers in major banana-growing
areas of Uganda, suggesting that these are
preferred, given the many constraints farmers
face and current field conditions. The
seven cultivars chosen for the analysis include
two that are both widely grown and
were initially identified for assays (Mbwazirume
and Kibuzi), one that is widely
grown but not yet targeted for assays (Nakitembe),
and four that are identified, although
not as extensively grown (Nakinyika,
Enjagata, Kisansa, and Mpologoma). All
are endemic cooking cultivars of the East
African highlands.
Explanatory variables
The determinants of cultivar demand include
household (Ω HH , I), farm (Ω F , v- , ṽ) and
market characteristics (p Ω M ) and cultivar
attributes (z C , zP ), as specified in the reduced
form equation (9). 5 The comparative
statics of a nonseparable agricultural household
model are complex, and in general,
unambiguous signs on the direction of effects
cannot be derived. Hypothesized effects
are supported by observations from
banana research or the literature on seed
innovations in developing economies.
Explanatory variables are defined and
summarized at the household level (Table
6.1) and at the cultivar level (Table 6.2).
Household characteristics include the expe-
4
Endemic banana cultivars are classified into five clone sets. The 67 cooking cultivars identified in the sample
are variants within four of these clone sets, with the fifth one representing endemic beer cultivars. The seven
cooking cultivars used in the analysis span the four clone sets.
5
No data were available for prices of other goods purchased by the household ( p G ). This variable was not
included in the analysis.