A Research on Change Point and Trend Scrutiny: with Reference to Castor in India

Abstract

Castor is treated as an important non-edible oil crop among Mahua, Karanja and Jatropha. India occupies a leading position in the production of castor followed by China and Brazil. Castor has been used in various purposes from thousands of years ago which has important characteristics. The main objectives of current work are i) Identification of change point and ii) Trend analysis with respect to area, yield and production of castor for the period from 1961 to 2016 in India. The non-parametric statistical methods such as Pettitt's, Standard Normal Homogeneity (SNH) and Buishand’s Range tests have conceded to detect the mutation point whereas the magnitude of trend is measured and analysed with the help of Sen’s slope estimator and their significance is tested by Mann-Kendall test. The results revealed that the change is identified by mutation point at initially 1988. Interestingly the maximum growth is captured in the second sub-time series on the basis of time scale and area, yield and production. However, the production of castor cannot meet up its annual enormous demand for India.