I initially created Baseball Graphs to develop new and better ways of presenting baseball statistics. The 2003 season was my first full-season attempt, and it turned out pretty well. I now spend a lot of my time creating and formatting the baseball stats at The Hardball Times.
Along the way, I've also picked up the writing bug. I spend most of my energy writing for THT, but sometimes I like to write about more geeky stuff, baseball research and things like that. That's what this blog is for.
I'm very interested in graphics and other information display, so I'll probably post links to creative stuff like that. I also plan to write historical articles that complement the historical graphs. And I have inexplicably developed an interest in baseball win-related stats, such as Bill James's Win Shares and something called Win Probability Added. So you can expect a few posts about that stuff too.
If you're interested, I've created a complex spreadsheet full of WPA logic, which you can download at ftp.baseballgraphs.com/wpa. If you'd like to read more about Win Shares, try these links:
Win Shares Intro
A sharper look at the replacement levels of Extreme Win Shares
In the Extreme Win Shares article, I used a replacement level equal to 50% of each player’s Win Shares Baseline (which is the average number of Win Shares in the league, given that player’s playing time). Why 50%, instead of the more common 85% (or thereabouts)?
Because Win Shares already has a pseudo-replacement level buried inside it, based on the Marginal Runs concept. So I took a stab at the additional replacement level required to bring the overall system close to something that made sense. And 50% was as good a number as any.
So how did I do? To find out, I subtracted each team’s total Win Shares above replacement from total Win Shares to calculate the implied replacement wins. Win Shares minus WS above replacement equals replacement Win Shares.
The average replacement Win Shares were 122, or 41 wins (rounded off). This is pretty good, I think. The Tigers, who were about as replaceable as you can get, won 43 games last year.
Team, by team, the results varied from 39 (Tigers) to 42 (Astros). This wasn’t quite as consistent as I had hoped for—I think I was hoping for a spread of one win—but it’s not bad.
Looking over the data, I also think you can discern a decent rule of thumb for individual replacement Win Share levels: eight Win Shares for a full-time position player, six Win Shares for a starter, and five Win Shares for a closer.
I know this can and should be improved, but I’ll take it for now.
I also seem to recall reading somewhere that the statistical bounds on team wins is something like 45 on the low end and 115 on the high end, so having the “replacement” team level around 41 is certainly pretty close.
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