The Beginnings of Base Runs
I recently came across the original newsgroup post from December of 1999 where David Smyth introduced his run estimator Base Runs. I also found archived versions of the summary he posted a few months...
View ArticleAdjusted Plus-Minus in Hockey
Though plus-minus originated in hockey and has been tracked by the NHL since 1968, development of the stat really picked up when it was adopted for use in basketball in the last decade. In 2000 Wayne...
View ArticleA Perl version of Tango’s Markov Model
I have created a Perl version of Tangotiger’s excellent Markov run modeler. Tango’s original HTML/Javascript version can be found here, with further discussion here. This is just a basic adaptation – I...
View ArticleThe Origins of Log5
Of all Bill James’ sabermetric innovations, my favorite has always been the log5 formula for determining matchup probabilities. It provides a method for taking the strengths of two teams and estimating...
View ArticleThe Distribution of Talent Between Teams
Four years ago Tango had a very interesting post on how talent is distributed between teams in different sports leagues. I want to revisit and expand upon some of the points that came up in that...
View ArticleBuilding a Retrosheet Database, Part 1
I want to be able to calculate Tangotiger’s WPA/LI stat (Win Probability Added/Leverage Index, a.k.a. situational wins, context neutral wins, or game state linear weights). To do that, I need to be...
View ArticleRun Expectancy and Base-Out Leverage Index
Before I get into win expectancy, Win Probability Added, Leverage Index, and WPA/LI, I want to take a look at run expectancy, RE24, Base-Out Leverage Index, and RE24/boLI. Most of these stats were...
View ArticleRun Expectancy and Markov Chains
Sorry for the long interval between entries – I hope to get back to posting on more regular basis. Continuing in the vein of my previous two posts, I’m still working my way towards baseball win...
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