Technical Efficiency of Sweet Potato Production: A Stochastic Frontier Analysis

The level of yield among sweet potato farmers is on a decline; low output and yield differences was observed, indicating the existence of inefficiency in production systems and variations in input utilization. Efficiency in resource use must be sustained in order to improve productivity and maximize farm output. This study therefore analyzed the technical efficiency of sweet potato production. Multi-stage sampling techniques were adopted in selecting 94 respondents for this study. Data collected was analyzed using descriptive statistics and stochastic frontier production function. The socioeconomic variables of the respondents affected their farm efficiency and level of farm output. The estimated ratio of the L/R test was 0.579; indicating a goodness of fit of the frontier model and thus a rejection of the null hypothesis. The coefficients of sweet potato seeds (vines) (0.362) and labour (0.439) were positive and statistically significant at 5% level of probability, while the coefficients of farm size (-1.333), fertilizer (-0.452) and herbicides (-0.766) were negative but statistically significant at 5% level of probability. The inefficiency model revealed that the coefficient of farm capital (-0.172), education (-2.281), access to credit (-0.472), farming experience (-0.639), extension contact (-0.733) and membership of cooperatives (-0.396) were negative and statistically significant at 5% level of probability. The mean technical efficiency was 0.62 (62%) implying that the sweet potato farmers in the study area were not producing at optimal capacity. The constraints identified significantly affected sweet potato production in the study area. Subsidizing input costs; sensitizing farmers on appropriate farming practices, cooperative formation and efficiency in resource utilization; improving access to agricultural inputs, technology, farm capital, credit and extension services, market linkages, farm labour supply and the development of indigenous technologies in sweet potato production are strongly recommended.