from tangotiger’s page
http://www.insidethebook.com/li.shtml

just bottom of the 9th, 3 outs to go, bases empty.
up by 1, 3.6 LI, 1.5 FSV
up by 2, 2.0 LI, 0.8 FSV
up by 3, 1.0 LI, 0.5 FSV

FSV is a nice idea in that it tries to take some of the save context into consideration and put the results on the saves scale. What might be a fun project is to use WPA (which already has the real context FSV tries to approximate, and more, like base state, home vs road) and put that on a saves scale to make it more accessible.

The latter example would result in a lower FSV even though it is a much tougher situation.

I’d also like to somehow work in the type of batters faced. Though it is ultimately left to chance it is something I’m very curious about. Recording a 1-run save in the ninth against guys like Adam Everett and Nick Punto is much different than facing Utley-Howard-Burrell.

Just because you get a number that seems reasonable doesn’t mean it is reasonable. Look at BP’s LEV as an example of a good idea gone bad.

If a Closer enters into the top of the ninth, with a 1-run lead, he would get an FSV of 1.50 for that game because it’s just the three outs and one-run lead that matters.

If we look at that with LI, he would be entering into an LI of +2.9. Looking at WPA, getting a 1-2-3 save in the ninth, with a 1-run lead, would result in a WPA of roughly 1.34.

So, using the FSV it would be 1.50, using the SV it would be 1.23, and using WPA it would be 1.34, though WPA takes everything that occurs in the inning into account. The Save Value stats look solely at the entering situation.

In terms of contribution to a team’s wins, WPA and WPA/LI are going to be more indicative, but the SV and FSV make the Saves statistic useful by gauging the difficulty level in recording said saves while still representing it with a number close in appearance to the Saves total.

If Romero pitches 0.2 IP in 9 games, it comes out to 6 IP. Now, if he is perfect in 8 of those 9 games, but in Game #9 he gives up a walk, single, and three run homer, he is going to end up with a 4.50 ERA, an ERA we don’t consider too good for a reliever.

Despite this, he would have done his job a remarkable 89% of the time. I’m still confident in him but definitely agree his ERA is misleading because what he is asked to do is strand runners and get lefties out. He’s gotten lefties out as they are currently just 2-20 with 1 BB off of him, but 5 of his 11 inherited runners have scored.

It would likely result in using a baseline similar to ERA+ and OPS+ where 100 is average and above that is that specific percent better than the average.

So instead of looking at JC Romero and seeing he gets a score of +24.1, which would be vague unless looked at in the scope of a league leaderboard, we could say his Relief Score is 154; his results are 54% better than the average short-specialist.

For specialists I have in mind something similar to the LWTS Runs for each pitch thrown; since they face so few batters each pitch is very important. Factoring in that for the pitches thrown as well as an ongoing additive component of each out recorded and the difference in expected runs.

That could then be applied to non-specialist relievers, but without the pitch lwt-runs.