A year ago over at Project Prospect, Brett Sullivan came up with a metric called Dominance Factor. It's intended to be an unbiased
statistic to show the extent a pitcher is dominating, taking different variables such as Age, K rate, BB rate, GB rate, and the level the pitcher is pitching
at, similar to Mike's Age Advancement Scale here at SP. It's
completely defense-independent, takes everything a pitcher can control, and IMO, does a pretty accurate job at showing how dominant a pitcher has been. So, I
dug up a few numbers from FR9's pitching stats page
and plugged them into the formula, which is:
Dominance Factor (DF) = (Strikeout Percentage + Groundball Percentage (*0.72) - Walk Percentage) + ((Age-Level standard - actual age) *7)
Age-Level Standard is as follows:
Age-Level standards:
Rookie = 19.0 (I added this one so I could put Mendez and Rivera on here)
Low-A = 20.0
High-A = 21.0
AA = 22.5
AAA = 24.0
And chose the current Top 40 Prospects with at least 20 IP this year (only excluded Britton), and came up with this:
To compare that with other prospects over the past couple years, click here.
edit: it should be duly noted here w/r/t pitchers with Age Mod's such as Adam Mills' -8.4 that I weighted their innings spent pitching for multiple affiliates. (ie, 80% of Mills' IP were in Portland, so his Age/Level Standard was weighted 80% in favor of Portland)
My comments:
1. Age factor played a pretty significant part into how dominant they were in 2009, but was completely justified, IMO.
2. You don't need to be a strikeout pitcher to be dominant (I suspect I'll get a lot of bashing here).
3. I've developed a newfound interest in ground ball pitchers.
Now, like any metric, you can't take this as gospel. But, I think it does a pretty solid job at what it's trying to tell you. I'm open to hear any criticisms of DF if you can think of anything. Also, if you find a pitcher in our system that had a pretty high (60+) DF, post it in here.
Dominance Factor (DF) = (Strikeout Percentage + Groundball Percentage (*0.72) - Walk Percentage) + ((Age-Level standard - actual age) *7)
Age-Level Standard is as follows:
Age-Level standards:
Rookie = 19.0 (I added this one so I could put Mendez and Rivera on here)
Low-A = 20.0
High-A = 21.0
AA = 22.5
AAA = 24.0
And chose the current Top 40 Prospects with at least 20 IP this year (only excluded Britton), and came up with this:
To compare that with other prospects over the past couple years, click here.
edit: it should be duly noted here w/r/t pitchers with Age Mod's such as Adam Mills' -8.4 that I weighted their innings spent pitching for multiple affiliates. (ie, 80% of Mills' IP were in Portland, so his Age/Level Standard was weighted 80% in favor of Portland)
My comments:
1. Age factor played a pretty significant part into how dominant they were in 2009, but was completely justified, IMO.
2. You don't need to be a strikeout pitcher to be dominant (I suspect I'll get a lot of bashing here).
3. I've developed a newfound interest in ground ball pitchers.
Now, like any metric, you can't take this as gospel. But, I think it does a pretty solid job at what it's trying to tell you. I'm open to hear any criticisms of DF if you can think of anything. Also, if you find a pitcher in our system that had a pretty high (60+) DF, post it in here.
