### General NERP assistance

Posted:

**Wed Mar 29, 2017 9:30 am**Diamond Dope does a wonderful job with their tool to make it easy for people to see the various calculations like NERP and BR, without manually doing a lot of work.

My questions revolve around how I should think about these results, the context of the 50/50 probability that the card I am looking at will be in play on any given roll:

First, the NERP calculation is based on the assumption that 100% of the rolls are coming from the card that is being evaluated. This is logical and rational. But I am not sure how to conceptually apply these values to the situation that half the rolls will be coming from the universe of other cards in play.

For example Greg Maddux 1995 has a NERP against lefties of -5.36 at Turner Field. How would I think about applying that against a starting lineup of hitter each of whom have an average NERP of 20. Is it simply a matter of taking the average of -5.36 and 20, which is 7.32? That result seems much higher than I would expect the game play to work out, so my conclusion is that there must be another to way to think about it. Any help would be appreciated.

My questions revolve around how I should think about these results, the context of the 50/50 probability that the card I am looking at will be in play on any given roll:

First, the NERP calculation is based on the assumption that 100% of the rolls are coming from the card that is being evaluated. This is logical and rational. But I am not sure how to conceptually apply these values to the situation that half the rolls will be coming from the universe of other cards in play.

For example Greg Maddux 1995 has a NERP against lefties of -5.36 at Turner Field. How would I think about applying that against a starting lineup of hitter each of whom have an average NERP of 20. Is it simply a matter of taking the average of -5.36 and 20, which is 7.32? That result seems much higher than I would expect the game play to work out, so my conclusion is that there must be another to way to think about it. Any help would be appreciated.