In prior posts, I demonstrated how to download projections from numerous sources, calculate custom projections for your league, and compare the accuracy of different sources of projections (2013, 2014). In the latest version of our annual series, we hold the forecasters accountable and see who had the most and least accurate fantasy football projections over the last 3 years.
The R Script
You can download the R script for comparing the projections from different sources here. You can download the historical projections here and historical performance (i.e., players’ actual points scored) here.
To compare the accuracy of the projections, I use the following metrics:
Whose Predictions Were the Best?
|Fantasy Football Analytics: Average||.671||.422||.503||.520||.569||.479||.581||.474|
|Fantasy Football Analytics: Robust Average||.566||.483||.566||.483|
|CBS: Jamey Eisenberg||.619||.501||.388||.676||.465||.614||.491||.597|
|CBS: Dave Richard||.619||.501||.388||.676||.512||.587||.507||.588|
|Footballguys: David Dodds||.534||.527||.534||.527|
|Footballguys: Bob Henry||.566||.479||.566||.479|
|Footballguys: Maurile Tremblay||.527||.523||.527||.523|
|Footballguys: Jason Wood||.549||.495||.549||.495|
- Fantasy Football Analytics: Average
- Footballguys: Bob Henry
- Fantasy Football Analytics: Robust Average
- Footballguys: Jason Wood
- Footballguys: Maurile Tremblay
- EDS Football
- Footballguys: David Dodds
- CBS: Dave Richard
- CBS: Jamey Eisenberg
Notes: FantasyFootballNerd projections were not included because the full projections are subscription only. WalterFootball projections were not included because they do not separate rushing from receiving touchdowns. CBS estimates were averaged across Jamey Eisenberg and Dave Richard in 2012 and 2013.
Here is a scatterplot of our average projections in relation to players’ actual fantasy points scored in 2014:
- Projections that combined multiple sources of projections (FFA Average, FantasyPros) were more accurate than single projections (CBS, NFL.com, ESPN).
- The R-squared of the FFA average projection was .67 in 2012, .50 in 2013, and .57 in 2014. This suggests that players are more predictable in some years than others. It also indicates that 1/3 to 1/2 of the variance in actual points is unexplained by projections, so there is much room for improvement in terms of prediction accuracy.
- There was little consistency in performance across time among sites that used single projections (CBS, NFL.com, ESPN). In 2012, CBS was the most accurate single source of projection but they were the least accurate in 2013. Moreover, the least accurate in 2012 was NFL.com, but they were among the most accurate in 2013. This suggests that no single source reliably outperforms the others. While some sites may do better than others in any given year (because of fairly random variability–i.e., chance), it is unlikely that they will continue to outperform the other sites.
Fantasy Football Analytics had the most accurate projections over the last three years. Why? We average across sources. Combining sources of projections removes some of their individual judgment biases (error) and gives us a more accurate fantasy projection. No single source (CBS, NFL.com, ESPN) reliably outperformed the others or the crowd, suggesting that differences between them are likely due in large part to chance. In sum, crowd projections are more accurate than individuals’ judgments for fantasy football projections. People often like to “go with their gut” when picking players. That’s fine—fantasy football is a game. Do what is fun for you. But, crowd projections are the most reliably accurate of any source. Do with that what you will!