from Amazon
Saturday, July 25, 2009
Are in-season PECOTA’s reliable?
Tango,
At Baseball Prospectus, they’ve added in-season PECOTAs. I took their pre-season PECOTAs and matched them up with what PECOTA is projecting for the remainder of the season and I’m very surprised at some of the differences. From all I’ve read at your site, some of these projections look way out there. I just can’t believe that a half-season worth of stats can change a projection as much as they have for some of these players. For example:Jason Bartlett pre-season PECOTA projection (using 3/21 Player Forecast Manager projections):
.257/.311/.346Bartlett’s updated PECOTA projection for the remainder of the season:
.307/.356/.440That’s a pretty extreme difference (.139 higher OPS). Also, Bartlett’s season line is still strong (.338/.388/.515), but since June 1, he’s hit .288/.344/.396. He’s not the only one, just the most extreme. Other extreme examples:
Kendry Morales
Pre-season PECOTA: .252/.294/.388, .682 OPS
Rest of season PECOTA: .277/.330/.482, .812 OPSJoe Mauer
Pre-season PECOTA: .307/.388/.436, .824 OPS
Rest of season PECOTA: .328/.416/.504, .920 OPSAnd, those with much more pessimistic projections:
Jimmy Rollins
Pre-season PECOTA: .293/.360/.458, .818 OPS
Rest of season PECOTA: .247/.310/.397, .707 OPSKelly Johnson
Pre-season PECOTA: .287/.371/.468, .839 OPS
Rest of season PECOTA: .241/.315/.392, .707 OPSI found similar extreme projections for pitchers, such as Zack Greinke:
Pre-season PECOTA: 4.01 ERA, 1.30 WHIP
Rest of season PECOTA: 2.97 ERA, 1.07 WHIPI guess I’m just curious what you think. It looks to me like this year’s data has been too heavily weighted in their creation of rest-of-season PECOTA projections.
-- Bobby Mueller
Recent comments
Older comments
Page 1 of 343 pages 1 2 3 > Last »Complete Archive – By Category
Complete Archive – By Date