Abstract:The 186 sets of CPI index data from 2000 to 2015 years in China reflected some rules, which can be described by Channel principle and the corresponding method. Channel is a data channel with the largest security sense,which based on Chebyshev approximation theory,to the CPI function as its center line, to minimize the maximum positive and negative error as its boundary line,and contains all the CPI data.Assuming that the endpoint data is the largest weight data based on zero error, there is no mutation of CPI index in the short term, or mutation but the error is less than channel's maximum positive and negative error,then the future CPI index can be given by the channel through the forecast value and fluctuation value.This article introduced the CPI channel principle and its method, the applicable scope, the judging rules,the concrete algorithm, etc.Through some examples of data processing, this paper shows that the straight line channel is easy to understand, intuitively simple and strong, convenient in the computation, broad in the applicable scope, good in the compliance, and also verifies that the scope of future short-term changes in the CPI index is knowable and controllable. |