As we dive head-first into the start of the NFL season, here is a quick explanation of each of the three Strength Ratings offered each week for every game in the various sports we cover:
• The Power Ratings (PR) are my own manually adjusted ratings updated after every game based upon analysis of live action and box scores
• The Effective Strength Ratings (EffStr) are purely statistical ratings, using the teams’ key stats against schedule strength and their previous opponents’ averages. These are also adjusted for any key injuries the team had endured or faced against.
• The Bettors Ratings (BtrRtg) are a quantified interpretation of how bettors perceive teams based upon how lines of recent games have moved and closed.
Some important points: 1) On injuries situations where a key line move player is listed as doubtful or out, I have already built the adjustments into the ratings. Where the player is questionable or probable, I have not, so if that player ends up missing then the reader needs to account for those on their own. 2) Each morning I do go back and make postgame adjustments to the ratings based upon results, closing lines, and injuries for the purpose of future numbers. 3) Point spread projections (proj) are built for the home team. In other words, if the number is positive, that means the road team would be favored.
In general, the best practice is to use the ratings and scores (scr) as a basis of where to expect the lines to be when they come out and/or they close. While I stand behind the Strength Ratings’ for their quality, validity, and the methods by which each is built, tracking the records against the actual lines is the only way to verify the success rates of each.
Over the course of a day or week, the lines for some games will change. Unless a player is out, the ratings only change on a day to day basis based on games played. I personally update the ratings daily, but obviously for uses in the Point Spread Weekly, I cannot present the daily changes. It is in “overadjustments’ by oddsmakers daily that a lot of value can be found.