CSS Button No Image Css3Menu.com

Baseball Prospectus home
  
  
Click here to log in Click here for forgotten password Click here to subscribe

Premium and Super Premium Subscribers Get a 20% Discount at MLB.tv!

<< Previous Article
Premium Article Minor League Update: G... (08/20)
<< Previous Column
Premium Article Baseball Therapy: Usin... (08/12)
Next Column >>
Premium Article Baseball Therapy: Ryan... (08/23)
Next Article >>
Premium Article Overthinking It: Steph... (08/20)

August 20, 2013

Baseball Therapy

Saving the Save

by Russell A. Carleton


Last week, I asked the question of whether teams should use their best reliever (the closer?) to protect a three-run lead in the ninth (a "cheap" save) or to prevent a one-run deficit in the ninth from getting bigger in the hopes of scoring and either tying the game or going ahead. Despite the fact that sabermetric wisdom says a closer should be used when the game is... close-er, it actually makes more sense to protect the bigger lead than to chase what is nearer to a lost cause than we might like to admit.

Let's formalize that, shall we?

Many of the fine folks who read Baseball Prospectus will be familiar with the concept of Leverage Index, invented by noted sabermetrican Tom Tango (and if you are you can skip this paragraph). Leverage Index begins with the concept of win probability, which is the idea that if I know the score, the inning, the number of outs, and where the runners are, I can look up how often a team has won or lost in games that featured the same set of circumstances. There are some situations where the possibilities for a big change in win probability, in one direction or the other, are high. Think of the home team being down a run in the bottom of the eighth, but with runners at second and third with two outs. What happens in this plate appearance will have a large influence on what happens in the game. Compare that to a plate appearance in the sixth inning of a 15-2 game. It doesn't matter what happens there. The Leverage Index is a way of mathematically formalizing the potential impact of an individual plate appearance on a game's outcome.

The Leverage Index is great if you want to make decisions or analyze outcomes from plate appearance to plate appearance. The problem is that not all decisions are made from plate appearance to plate appearance. The biggest one is constructing a strategy for using the bullpen. There will be situations where managers make decisions based on one or two hitters (probably involving a LOOGY), but since the dawn of the one-inning closer, who begat the one-inning eighth-inning set-up guy, bullpen strategy has focused ever more on relievers who are sent out to start and finish a single inning. The merits of this system are debatable, but since that is the way the game is structured, how can we figure out which innings managers should prioritize?

To do that, I created a small wrinkle on the Leverage Index.

Warning! Gory Mathematical Details Ahead!
The scoreboard does not know (or care) whether a pitcher who recorded a scoreless inning did so after loading the bases and then tiptoeing his way out of the jam or whether he struck out the side on nine pitches. When we look back at the linescore for the day, there will be a zero in that spot. Instead of looking at the changes in win probability that can happen from plate appearance to plate appearance, I looked at the top and bottom of each inning (with the ninth inning and extra innings all in the same bin), and each possible score differential at the beginning of the inning (with anything seven or more all rolled together). Since it's the beginning of the inning, there are no outs and no runners. I then looked at what the win probability was for each team after that half-inning was all said and done.

The rest of this article is restricted to Baseball Prospectus Subscribers.

Not a subscriber?

Click here for more information on Baseball Prospectus subscriptions or use the buttons to the right to subscribe and get access to the best baseball content on the web.


Cancel anytime.


That's a 33% savings over the monthly price!


That's a 33% savings over the monthly price!

Already a subscriber? Click here and use the blue login bar to log in.

Related Content:  Saves,  Closer,  Bullpen Usage

14 comments have been left for this article.

<< Previous Article
Premium Article Minor League Update: G... (08/20)
<< Previous Column
Premium Article Baseball Therapy: Usin... (08/12)
Next Column >>
Premium Article Baseball Therapy: Ryan... (08/23)
Next Article >>
Premium Article Overthinking It: Steph... (08/20)

RECENTLY AT BASEBALL PROSPECTUS
Premium Article Minor League Update: Games of Tuesday, July ...
BBQ State of Mind
Eyewitness Accounts: July 30, 2014
Premium Article Scouting the Draft: The Cape League All-Star...
The Lineup Card: Nine Last-Minute Trades
Premium Article Moonshot: Separating the Phenoms Who'll Make...
Premium Article Transaction Analysis: Cardinals Vouch for Ma...

MORE FROM AUGUST 20, 2013
Hot Prospect Video
Premium Article Transaction Analysis: Bye Charlie
Premium Article The Prospectus Hit List: Tuesday, August 20
Premium Article Transaction Analysis: Boston, Xander Bogaert...
Fantasy Article The Stash List: The Final 2013 Installment
Fantasy Article Fantasy Freestyle: Should I Play for "The Mo...
Premium Article Daily Roundup: Around the League: August 20,...

MORE BY RUSSELL A. CARLETON
2013-08-28 - Premium Article Baseball Therapy: Matt Harvey and the Increa...
2013-08-26 - Premium Article Baseball Therapy: Baseball: Like Nothing You...
2013-08-23 - Premium Article Baseball Therapy: Ryan Dempster, Alex Rodrig...
2013-08-20 - Premium Article Baseball Therapy: Saving the Save
2013-08-12 - Premium Article Baseball Therapy: Using the Closer to Keep a...
2013-08-06 - Premium Article Baseball Therapy: Prioritizing the Pitcher's...
2013-07-30 - Premium Article Baseball Therapy: Leave Me In, Coach!
More...

MORE BASEBALL THERAPY
2013-08-28 - Premium Article Baseball Therapy: Matt Harvey and the Increa...
2013-08-26 - Premium Article Baseball Therapy: Baseball: Like Nothing You...
2013-08-23 - Premium Article Baseball Therapy: Ryan Dempster, Alex Rodrig...
2013-08-20 - Premium Article Baseball Therapy: Saving the Save
2013-08-12 - Premium Article Baseball Therapy: Using the Closer to Keep a...
2013-08-06 - Premium Article Baseball Therapy: Prioritizing the Pitcher's...
2013-07-30 - Premium Article Baseball Therapy: Leave Me In, Coach!
More...

INCOMING ARTICLE LINKS
2014-04-15 - Premium Article Baseball Therapy: Why Sabermetrics Needs Tra...