We search through historical data looking for anomalous patterns that we would not expect to occur at random. Our scheme is to analyze data and markets to test for statistical significance and consistency over time. Once we find one， we test it for statistical significance and consistency over time. After we determine its validity， weask， ‘Does this correspond to some aspect of behavior that seems reasonable？’

"The past is always with us, for it feeds the present."

因此，教学艺术无非是时间、科目和方法的巧妙安排。