March 12, 2014
Baseball Prospectus News
10-Year Projections, UPSIDE, Percentiles, and Comparables
Baseball Prospectus is pleased to announce five new additions to the 2014 player cards, three which have been missing for a few years.
The original intended use for UPSIDE and long-term projections was to aid in discerning how various prospects might do during the time when their organization had control over them (or roughly five full-time seasons). And the methodology was based on using actual performance of the most-comparable players over the years in question. There have been some changes to the details over the years, but the core concept has been brought back for 2014, with projections through 2023. Here are some clarifications of what we're doing now:
We'll be using UPSIDE to compare PECOTA's top prospects to those of the BP Prospect Staff in an upcoming article series, so stay tuned for that.
Now for the fun stuff. To get to the new features without scrolling all the way down the player card, simply click on the "More PECOTA" tab located near the middle of the navigation bar:
From there, all the new features follow one after another:
The "PEAK 5" UPSIDE value for Sogard is the sum of his first five UPSIDE scores, as he's beyond the age where the system considers other options.
Last but not least are the most-comparable players based on similarity score. "The comparables," as Colin Wyers put it, "represent a lot of tedious number crunching (measuring Euclidean distance in n-th dimensional space, if you want to be precise)." The "Similarity Index" is based on the Similarity Scores of the top 100 most-comparable players. And the Similarity Scores are based on the Euclidean distances between the player in question (in this case, Sogard in 2014, which will be his age-28 season) and every other player in our database at the same age (for example, Jeff Keppinger in 2008—his age-28 season).
The "Trend" column can be a bit confusing—it's a simple up/down/neutral metric based on whether the comparable player over- or under-performed his baseline projection by 20 percent. For the "baseline" projection, only a generic aging curve is used for comparisons—the system doesn't evaluate the player's projection based on his comparables. Protip: Note the easily-overlooked arrow on the bottom right, which allows for the selection of comparable players 11-100.
We hope you enjoy these PECOTA-related offerings. If you have questions about methodology or navigation, please post them in the comments below or email customer service.