Skip to main content


Table 1 Definition of variables

From: Correcting for sample selection in stochastic frontier analysis: insights from rice farmers in Northern Ghana

Variable Definition/measurement Sign
Output Natural log of rice output (measured in 100 kg bags) +
Age The total number of years from birth +
Sex Dummy: 1 for male, 0 if otherwise +
HH head Dummy: 1 for household head, 0 if otherwise +
Education Number of years spent in formal schooling +
Commercial Dummy: 1 if farmer produces for commercial purpose, 0 if otherwise +
Experience The total number of years a farmer has been cultivating rice. +
Region Dummy: 1 for a farmer in Northern Region, 0 for a farmer in Upper East Region +/−
FBO Dummy: 1 for if the farmer belongs to a farmer group, 0 if otherwise +
Research/extension Dummy: 1 for access to research/extension service, 0 if otherwise +
Credit Dummy: 1 for access to credit in the last growing season, 0 if otherwise. +
Training Dummy: 1 if farmer had access to trainings last season, 0 if otherwise. −/+
CC perception Dummy: 1 for farmers who perceived that rainfall was reducing with rising temperatures, 0 if otherwise +/−
HH size Total number of people in housing unit that feed from the same source +/−
Farm size Natural log of farm size (measured in the acres of land under rice production) +
Herbicides Natural log of quantity of herbicides (measured in litres) used +
Fertilizer Natural log of total quantity of fertilizer (measured in kg) +
Seed Natural log of quantity of improved seed (measured in kg) +
Labour Natural log of total number of persons available that worked on the farmers field during the farming season