Here is how their methodology works:   In theory, if you knew exactly what price a stock would be immediately before earnings, you could purchase the corresponding straddle a number of days beforehand. To test this, we looked at the past 4 earnings cycles in 5 different stocks. We recorded the closing price of each stock immediately before the earnings announcement. We then went back 14 days and purchased the straddle using the strikes recorded on the close prior to earnings. We closed