We have two outstanding matchups on tap for conference championship weekend, as the 49ers battle the Eagles in Philadelphia before the Chiefs host the Bengals on CBS and Paramount+ in a rematch of last year's AFC Championship. My power ratings had the right side on three of the four matchups last week, only missing the Chiefs cover due to a late field goal by Jacksonville while down 10 points. I found reasons to veer away from some of those sides in my own picks and paid a price for it. Will I make the same mistake again this week or back what the ratings say?

What are power ratings? Well, anyone who has followed football (or really any sport) for any length of time has encountered a power rankings list that projects teams from best to worst. Where power ratings for NFL betting differs is that you're affixing a point total to each team that tells you how much better or worse it is from an average team. For example, if you think the Giants are the midpoint of the league, their power rating would be a zero. If you think the Jaguars are a little bit better, you might make them a +1. The Cowboys may be another step above and worth a +2 rating. Going the other way, you may think the Dolphins are a -1 or -2 team (or even worse).

After you've rated all 32 teams in this fashion, you can take the difference between two teams in a scheduled matchup to determine what the line would be on a neutral field. In our example above, we'd say the Cowboys should be favored by two points against the Giants on a neutral field. Then you add in home field advantage, which for a long time was considered three points as a standard but is actually lower on average in this era of football. I actually determine unique home field advantage totals for each team based on data from the last five years, and you can find my breakdown of this year's home-field advantage ratings here. I updated the HFA numbers of a few teams in my weekly workbook after six weeks and again after 12 weeks with a better understanding of which teams are good and bad, and which fan bases are likely to be more engaged than previously anticipated.

I've dived into each Week 21 game and evaluated my Week 21 power ratings to see what needed to be adjusted. I've also shared analysis of the most extreme differences between my projected lines and the market, as well as done the math to project the spread of every game based on my power ratings.

Which lines are several points off their power rating projections for the conference championships? And which teams are being undervalued by the market? ... Join SportsLine right now to see Week 21 power ratings from the expert who's 445-378-24 on ATS picks from 2017-21, returning $2,542 to $100 players!