from Amazon
Tuesday, September 13, 2011
Draft Order and Major League Pitching Performance…
I know there has been similar research published on the web, but I am too lazy to look it up right now. I took the 1998-2010 draft list from BA and looked at how the various pitchers did in the major leagues, breaking the rounds down into various buckets. It was a quick study and I just matched names from the draft lists with my major league databases. I probably missed 3-5% of the players because the names, especially first names, did not match up exactly.
First I looked at the rookie years for all pitchers in each draft round 1-3+, for a total of 4 buckets. Each round included the supplemental rounds, so, the first round actually has 60 picks in most years. The rest of the rounds pretty much have 30 picks each. Perhaps I should consider the first 30 picks of the 1st round as the 1st round and then the next 30 picks in the 1st round supplement as the 2nd round, etc.
Does anyone know if there is anything special about the supplemental round after the first 30 picks or is it just the next 30 best players and then the second round is 61-90 best players?
For each pitcher, I looked at whether their primary role in their rookie major league season was as a starter (S), a reliever (R), or mixed (N).
The currency I used was my normalized, component ERA (nERC), which is an “ERA” based on a pitcher’s raw stats (s, d, t, hr, nibb, hp, outs, and wp) adjusted for park, opponent, and defense, and normalized to his own league, where the average pitcher in each league, weighted by TBF, is 4.00. I weighted the aggregate nERC in each bucket by each pitcher’s IP. If I used the simple average of all the pitchers (weighting each pitcher exactly the same regardless of how many IP they threw), the numbers would be much higher, as the pitchers who had the worst true talent generally had the fewest IP.
“PS” is pitcher seasons.
Rookie year only:
Round Role PS IP nERC
1 R 41 1062 3.87
1 N 11 376 5.64
1 S 79 5485 4.39
2 R 24 507 4.41
2 N 6 101 6.86
2 S 31 2167 4.66
3 R 64 1375 3.83
3 N 19 575 4.81
3 S 42 2531 4.37
Here are the top 10 picks in the first round:
Top 10 R 8 228 3.79
Top 10 N 2 26 3.36
Top 10 S 30 2357 4.26
Here is the same list but with the 1st round supplement considered the second round, the second the third, etc., so that each round has around 30 picks:
Round Role PS IP nERC
1 R 34 871 4.09
1 N 6 236 4.71
1 S 56 4145 4.24
2 R 7 192 2.85
2 N 5 140 7.21
2 S 23 1340 4.84
3 R 24 507 4.41
3 N 6 101 6.86
3 S 31 2167 4.66
4+ R 64 1375 3.83
4+ N 19 575 4.81
4+ S 42 2531 4.37
This time it is each pitcher’s entire ML career (from 2000 to 2010), not just his rookie year:
Round Role N IP nERC
1 R 193 7744 3.70
1 N 42 2421 4.77
1 S 337 45468 3.81
2 R 111 4604 3.70
2 N 21 991 3.78
2 S 91 9327 5.15
3+ R 191 6753 3.90
3+ N 46 2688 5.00
3+ S 165 18738 4.13
Top 10 R 19 582 3.99
Top 10 N 14 670 5.05
Top 10 S 131 18579 3.62
Same list (entire ML career from 1998-2010) but with the 1st round supplement considered the second round, the second the third, etc., so that each round has around 30 picks.
Round Role N IP nERC
1 R 151 5818 3.72
1 N 26 1704 4.66
1 S 272 39515 3.73
2 R 42 1926 3.64
2 N 16 716 5.04
2 S 65 5953 4.33
3 R 111 4604 3.78
3 N 21 991 5.15
3 S 91 9327 4.15
4+ R 191 6753 3.90
4+ N 46 2688 5.00
4+ S 165 18738 4.13
I’ll present one more list. First, an explanation. If you have the above lists and I tell you that a 1st round (top 30 picks) pitcher is starting tomorrow for team X, and I ask you what you expect his nERA to be at the end of the season, would the correct answer be 3.73?
No. That is because the better pitchers have less attrition after their first start such that when we weight each pitcher’s season nERC by his IP, we get an aggregate nERC for each bucket which is less than “the average seasonal nERC for every rookie pitcher in each draft bucket.”
The only way to answer the question above (“What will this pitcher’s, who is making his ML debut tomorrow, nERC be at the end of the season?”) is to do the same analysis, but weight each pitcher’s seasonal nERC equally. So now the bad pitchers will get just as much weight as the good ones who threw lots more innings. If we do that, and only look at each pitcher’s rookie year, here is what we get. You’ll notice that the numbers are higher. These numbers should be close to the true talent of any pitcher who gets a ML debut.
Round Role N IP nERC
1 R 34 871 4.58
1 N 6 236 4.76
1 S 56 4145 4.74
2 R 7 192 5.15
2 N 5 140 7.01
2 S 23 1340 5.18
3 R 24 507 5.51
3 N 6 101 7.59
3 S 31 2167 5.76
4+ R 64 1375 4.70
4+ N 19 575 5.01
4+ S 42 2531 5.55
Top 10 R 8 228 3.73
Top 10 N 2 26 2.62
Top 10 S 30 2357 4.47
For comparison purposes, here are all pitchers in the major leagues (from 00-10), with each pitcher’s nERC weighted by their IP:
R 3892 158,677 3.74
N 463 29,895 4.76
S 2267 294,051 3.99
The same list with each pitcher season weighted equally:
R 3892 158,677 4.84
N 463 29,895 5.42
S 2267 294,051 4.57