ABSTRACT This article examines the efficiency of the National Football League (NFL) betting market. The standard ordinary least squares (OLS) regression methodology is replaced by a probit model. This circumvents potential econometric problems, and allows us to implement more sophisticated betting strategies where bets are placed only when there is a relatively high probability of success. In‐sample tests indicate that probit‐based betting strategies generate statistically significant profits. Whereas the profitability of a number of these betting strategies is confirmed by out‐of‐sample testing, there is some inconsistency among the remaining out‐of‐sample predictions. Our results also suggest that widely documented inefficiencies in this market tend to dissipate over time.

The first 100 days of a newly-elected President's administration are often a period of substantial and concentrated policy change. This paper shows that measures of uncertainty and risk aversion rise sharply during Presidential honeymoons. Consistent with theoretical models that suggest that investors demand compensation for bearing heightened political risk, we document striking spread returns to value, investment and profitability anomalies during honeymoons. For example, the book-to-market value premium averages 3.51% per month during Presidential honeymoons, yet only 0.27% per month at other times. These findings survive numerous robustness checks. Nonetheless, establishing a direct link between escalating political risk and equity returns proves challenging.