Comparison of Cobb-Douglas and Translog frontier models in the analysis of technical efficiency in dry-season tomato production

There has been contradiction among researchers regarding similarity or otherwise of technical efficiency estimate obtained from Cobb-Douglas and Translog frontier models. While some researchers believe that results obtained from the two functional forms, given the same data, were essentially similar, others disagreed. This study compared both functional forms to analyze technical inefficiency in dry-season tomato production in Jos-South Area of Plateau State. Data were collected from 60 dry-season tomato farmers sampled through three-staged random sampling technique. The analyses of the data were done using both Cobb-Douglas and translog frontier models. The results showed that the estimated elasticities, efficiency scores and inefficiency effects from Cobb-Douglas and Translog functional forms differ significantly. Therefore, the choice of functional form for efficiency analysis should be based on convenience, meeting selection criteria premise on the value of variance-parameters and objective of the study.Keywords: Efficiency, comparison, Cobb-Douglas and Translog model

Comparison of data envelopment and stochastic frontier models in analysis of efficiency and its factors in ginger farms in Kaduna State, Nigeria

Nigeria is trending below the top ginger producing countries of the world in terms of yield per hectare and national output. Technical Inefficiency due to poor combination and utilization of physical resources in the production of ginger is a major factor for low yield/output. Previous studies employed either Stochastic Frontier Analysis (SFA) or Data Envelopment Analysis (DEA) to measure technical efficiency. So, the question arises as whether the technical efficiency estimates from both methods are similar or not. The present study deployed the two common approaches (SFA and DEA) in estimation of technical efficiency and its determinants in order to ascertain the similarity or otherwise of the estimates. Two hundred and five (205) ginger farmers were randomly sampled for primary data collection. Analyses of the data were done through Descriptive Statistics, DEA, Tobit regression and SFA. The results show that means of the efficiency scores from both models namely DEA (0.70) and SFA (0.88) were significantly different at 1% probability level. However, estimates from both method suggest that the ginger farmers were operating at suboptimal level or below frontier. Also, the results of determinants of efficiency from two estimation methods (SFA and DEA-based Tobit regression) were dissimilar. While SFA method shows that household size, level of education and farming experience were responsible for enhancing the efficiency of ginger farms, none of these variables influenced the farmers’ efficiency under Tobit regression. Therefore, it is recommended that selection of efficiency estimation method between SFA and DEA by the researcher should be based on study objective rather than consideration on the premise of alternative opportunity. Also, greater output level or potential output can be achieved, given the current production technology, by educating ginger farmers on how to ensure that production inputs are combined and managed efficiently.Keywords: Comparison, DEA, SFA, Efficiency, Ginger Farm

Performance of Translog and Cobb-Douglas models in the estimation of technical efficiency of Irish potato production in Plateau State, Nigeria

The study compared the performance of Cobb-Douglas and Translog frontier models in the analysis of technical efficiency in Irish potato production in Plateau State. A multistage sampling technique was employed to select 180 respondents for the study. Data were analyzed using stochastic frontier model in the Cobb-Douglas and the Translog functional forms. Results revealed that farm size and seed had  positive and significant coefficients under the Cobb-Douglas model. However, estimated Translog model showed that, while farm size and labour had negative relationships with output, fertilizer had a positive relationship. The elasticity estimates from both frontier models show that Irish potato farmers were operating at an increasing return to scale. The mean technical efficiency estimates were 68% and 59% for Cobb-Douglas and Translog models respectively. Hypothesis testing showed that there was a significant difference in the technicalefficiency estimates between the Cobb-Douglas and Translog frontier models. The inefficiency estimates revealed that education, household size and extension reduced inefficiency while farming experience increased inefficiency under the Cobb-Douglas model. None of the socioeconomics variables analysed in the Translog model for inefficiency was significant. It is recommended that training of the farmers on the optimum rate of input utilization and combination should be organized. The Cobb-Douglas model provided better results, in terms of economic and statistical properties of the coefficients, and therefore recommended for the estimation of technical efficiency of Irish potato farms in the study area. Key words: Cobb-Douglas, performance, technical efficiency, translo