Fuzzy variable time series based on fuzzy membership function and econometrics

Econometrics is the field of economics that concerns itself with the application of mathematical statistics and the tools of statistical inference to the empirical measurement of relationships postulated by economic theory. Some variable data with fuzzy characteristics are neglected in empirical analysis. Since some econometrics data can have fuzzy characteristics, nothing but fuzzy logic can be applied. In this paper, some fuzzy characteristics of these variable data were discussed with fuzzy degree firstly. Then the author proposes the definition of fuzzy variable and fuzzy variable time series. And the mean and variance of fuzzy variable time series are presented at last. The fuzzy variable data are useful for econometric study and data mining.