1. 外推：如果分析的是时间序列数据(time series data),预测指利用过去和当前的信息对未来事件可能性的数值进行外推(extrapolating)估算,这与我们通常关于预测的理解一致,也是最狭义的预测定义;但是,如果分析的是横截面数据(CFOSS section data),
1. It is impossible to tell whether their investment strategies are on fire, or whether analysts are just extrapolating from a few faltering funds and fearing the worst.