The NFL pointspread market revisited: anomaly or statistical aberration?

An earlier paper by Lacey (1990) examined the National Football League betting market, using data from the 1984-1986 seasons. He tested 13 technical rules for betting and found several that had winning proportions significantly greater than 0.5 and were also profitable after transaction costs. That represented a violation of the weak form of the Efficient Markets Hypothesis. This paper provides an independent test of those same rules over the 1987-1995 NFL seasons. None of the strategies were profitable or had winning proportions significantly different than 0.5. Lacey's results were apparently just a statistical aberration rather than an exploitable anomaly. The results herein suggest the Efficient Markets Hypothesis was not violated.