## Win Expectancy and Run Expectancy 4/5/16

Hello, again! Afternoon game so I'm gonna try to do this tonight. It sucks that the Royals lost, but hopefully there's still some cool things we can see here.

First, hat tip to nom nom nom de plume, he told me more or less how Win Expectancy is calculated so I went and looked it up. Basically it's an average of every team in this exact same situation over the last 10 years and whether they went on to win the game or not.

Next I want to talk about a couple more stats I was intrigued by while looking at the play logs for Sunday night's and tonight's games.

Run Expectancy (RE): This is basically the same thing as Win Expectancy, but for runs. And instead of calculating a percentage they calculate a hard number. For example, in the current run environment this year every team has a .49 Run Expectancy at the beginning of the inning. So every team is expected to score about half a run every inning. Which I think is pretty cool. Obviously, this doesn't happen (And teams rarely score a run every other inning) but according to the math, it all averages to about that for now. I went back a bit and in 2010 the Run Expectancy at the beginning of an inning was .46. So people talk about there being less offense now, but apparently there was even less leading up to that point.

Run Expectancy for the 24 base-out States (RE24): This is the difference in Run Expectancy given the 3 different out states (0,1,2) and the 8 different base states (Any combination of runners at first, second, and third) between the beginning of an AB and the result. It sounds complicated, but it's pretty easy if you just realize it has the exact same relationship to Run Expectancy as as WPA has to Win Expectancy.

Link to today's Play Log: http://www.fangraphs.com/liveplays.aspx?date=2016-04-05&team=Royals&dh=0&season=2016

Box Score with WPA: http://www.fangraphs.com/liveboxscore.aspx?date=2016-04-05&team=Royals&dh=0&season=2016

What I find most interesting about the WE stat from today's game is that it takes going all the way down the 15th highest Win Expectancy before anyone scored any runs. (Neil Walker's 2 run home run was 15th at .51 Run Expectancy) The cool thing about RE24 is that Neil Walker's HR was actually worth 1.74 RE24. Because it was ultimately worth 2 runs by itself, and when it was over there was still a .26 WE for the Mets (I'm going to guess rounding errors are involved in the .01 discrepancy.)

Even though the Royals lost this game, they at one point had a better than 60% chance of winning it. If you guessed that was immediately after Escobar's lead off triple, you'd be right. At that moment the Royals had a 1.41 RE (before Moose struck out, actually the 6 top RE for either team lead to a strike out, rough day for hitters) The WE expectancy hovered around 50% after that until Walker's Home Run and never really got close to going back to the Royals' side.

Unsurprisingly, Morales strike out with the bases loaded in the 6th was both the worst WPA (-11.8%) and lowest RE24 (they went from a .76 RE to a 0 RE, can't score any runs with 3 outs) of the game for the Royals. Neil Walker's HR was similarly the highest WPA and RE24 (21.5%, 1.74 respectively) in the game for anyone, including the Mets. Unlike Sunday night's game which featured 2 plays over 20% and one above 16% there were no huge swings in this game.

Another interesting thing about this game, I suspect Neil Walker gets a lot of credit as the player of the game for the Mets, but by WPA that honor actually belongs to Syndergaard at 35% to Walker's 21%. Which makes sense if you think about it, Walker gave them 2 runs but the run environment suggests 4.5 runs is the average and Syndergaard kept the Royals from scoring any for 2/3 of the game. It's going to be hard to score enough runs if you only get 1/3 of the game to do it in.

It's a little bit different format this time, but after last time I realized I didn't want to put myself in a corner where some games were going to leave me without anything interesting to say, so I think I'll just find the stats that look interesting to me and talk about those. Again, any comments or suggestions are appreciated, especially if you can tell me how to get the Win Expectancy graph to embed itself!

This FanPost was written by a member of the Royals Review community. It does not necessarily reflect the views of the editors and writers of this site.