长期预报的相空间相似法

AN ANALOG METHOD OF PHASE SPACE FOR LONG-RANGE FORECAST

通过对分数维 D 的计算,我们用时间序列重建了一个 d=INT(L+D)维的相空间。而后,将统计预报的相似理论用于相空间的相点,并假设最近邻相点经演化时间 T 后模相等。根据这一假设,做了一些长期预报试验,其距平符号报准率一般为60—70%,相对误差一般不大于8%。

By way of the calculation of fractal dimension D,a phase space with d-dimensions ( d=INT(l+D)) is established using a time series.Then,the analog theory of statistical forecast isapplied to the phase points of phase space,and it is hypothesized that the mode of state at the near-est phase points after evolution time T is equal to each other.A lot of trial studies based on the hy-pothesis show that the forecast accuracy of anomaly sign can reach 60—70 per cent,and the rela-tive error is generally less than 8 per cent.