A while ago Tango wrote about the optimistic fan projections and I followed it up with a look at the fans’ playing time projections. I think the fan projections are very interesting and I wanted to look at another aspect before the season started. I wanted to see, broadly, how the fans’ projections compared with a computer-based system, like CHONE.
Here I plotted the FANS WAR projection versus CHONE WAR projection for each hitter with more than 15 fan projections. I use CHONE as the x-axis – not to say that I think it is the “independent” or “correct” variable, but just because one of them had to go on the x-axis. The red line is NOT the best fit line, but rather the y=x line. If the FANS and CHONE projected exactly the same values everything would fall along the line. Dots above the line are players whose FANS projection is higher and those below whose CHONE projection is higher. I added the names of a couple outlying points.
First off, there is a very strong positive relationship between the two projections: generally, players with a good FANS projection also have a good CHONE, and those with a poor projection of one have a poor one of the other. Not surprising, but reassuring to see.
Next, CHONE is more pessimistic than the FANS (or the FANS are optimistic). Most of the points fall above the line (FANS project higher WAR than CHONE). Interestingly, though, the FANS optimism (or CHONE pessimism) increases for better players. For below-average players (zero- to two-win players) there are a points below and above the line. But as you move up or right on the graph, almost all the players are above the line. The equation of best-fit line, FANS = 0.17 + 1.08*CHONE, bears this out. Since the slope is greater than one high-WAR players will have the greatest difference between FAN and CHONE projections. So the FANS optimism, relative to CHONE, is seen most in the best players.
Finally, I highlighted a couple outliers. The FANS really like Ian Desmond, Elvis Andrus and Evan Longoria compared to CHONE. The difference in each case is largely driven by a difference in defensive projection: the FANS think Andrus and Longoria will be elite defenders, CHONE thinks they will be just good; and the FANS think Desmond will be an average defensive shortstop, but CHONE thinks he will be quite poor. There were two players that CHONE liked considerably more than the FANS: CHONE likes Yuniesky Betancourt to be merely replacement level, while the FANS think he will be about a game worse; and CHONE sees Melky Cabrera as a three-win player while the FANS see him as a 1.5-win player. Finally I noted Troy Tulowitzki since he is one of the few superstars projected higher by CHONE than FANS. Again the difference is driven by defense. CHONE likes him to be an elite defender, while the FANS just a good defender.