Association of Agrometeorologists

Weather based fuzzy regression models for prediction of rice yield

RAKHEE, ARCHANA SINGH and AMRENDER KUMAR

Fuzzy regression models for forecasting rice yield in Kanpur district were developed and compared with the weather indices-based regression model. For this, weekly (23-35 SMW) weather data (1971, 1973-2011) were utilized. Significant variables in fuzzy approach were selected based on index of confidence (IC) and adequacy of models was compared with the weather indices-based regression models. It was found that variables such as total accumulation of minimum temperature, weighted interaction of bright sunshine hours and rainfall, weighted interaction of minimum and maximum temperature, unweighted interaction of maximum temperature and relative humidity in morning and weighted interaction of relative humidity in morning and evening respectively, are significant based on their IC and SSE (sum of square error) values. The validations of models were also attempted for three years (2008-09, 2010-11 and 2011-2012).This study also reveals that the parameters for adequacy of models for linear regression models vis-a-vis their fuzzy counterparts are much higher for all values of fitness criterion (h). Thus, fuzzy regression methodology is more efficient than linear regression technique.

Fuzzy linear regression; multiple linear regression; IC values, SSE, SST, SSR