Revisiting the Season Prediction

Several weeks back I predicted the number of runs the Orioles would give up and the number of runs the Orioles would score. The basis of this prediction depended on a few assumptions:

1) ZiPS/Morong Formula (my arrangement) would properly predict offensive and pitching performance.
2) Offensive replacements would cause a 10% reduction in run scoring while unearned runs would be ignored for pitchers.
3) Top 5 starters would start every game and provide an average of 6 innings pitched.
4) Relief pitchers would be league average.

1. ZiPS/Morong predicting performance.
ZiPS actually overpredicted the runs scored (with the run reduction application). ZiPS predicted that 193 runs would be scored. In actuality, 179 were scored. Even more of an issue was prediction of pitching performance. 222 runs were predicted, while 184 were actually scored. A major contribution to this error was the unexpected development of Daniel Cabrera and a bullpen that was much better than expected. It should be mentioned that my placeholder of a league average bullpen was actually somewhat optimistic. This formula under predicted the Orioles success.

2. Offensive reduction and static pitching.
My educated guess of a 10% reduction was pretty apt. Plugging in the actual OBP and SLG of each player resulted in a coefficient of 0.927 to reach the actual runs scored. The pitching prediction appeared a bit too kind. After plugging in the actual SP and RP era, the system predicted 177 runs, where there were actually 174 runs scored. The application of a coefficient (1.057) would have been appropriate to account for unearned runs.

3. Top 5 Starters would remain so and would average 6 IP.
It was to be expected that a starter or two would be injured. It was known this was a weak assumption. Loewen's injury made it so. The 6 IP prediction is actually almost right on the button.

4. RP would be league average.
Orioles RP are actually pitching 13% better than the league average bullpen.

New Adjustments

1. ZiPS is being replaced by PrOPS and xFIP.
As the season continues, in-season statistical methods may actually predict future performance better than season beginning predictions. The reason for this is that certain growth or degradation may not be apparent prior to the season. PrOPS takes in peripheral batting data to predict OBP and SLG. xFIP takes peripheral pitching performance data and predicts future ERA. Current relief pitching ERA will be multiplied by the coefficient factor mentioned in the next paragraph.

2. Performance Coefficients
The batting performance reduction coefficient will be changed from 0.9 to 0.927. The pitching performance coefficient will be changed from 1 to 1.057.

3. Record Calculation
The current record is considered a given, so the new predicted winning percentage will be applied to games yet to be played. The number of wins determined by the formula will then be added to the current total.

Team Used for Calculations
PrOPS/Morong
2 Roberts.........374obp/424slg
3 Mora............348/454
R Markakis........414/521
D Huff............324/441
L Scott...........328/395
1 Millar..........354/444
C Hernandez.......326/332
C Jones...........293/354
S Placeholder.....300/330

xFIP
S Olson...........3.75
S Guthrie.........4.19
S Cabrera.........4.19
S Trachsel........5.92
S Burress.........4.64
R Bullpen.........3.42

Results

In the games left, this method predicts the Orioles will score 542 runs and give up 537 runs. The season ending run totals would be 722 runs scored and 721 runs given up. In the remaining games, the winning percentage would be .505, which would end with us having a .518 winning percentage at the end of the year (Pythagorean Win Expectancy). This means that the current rendition of the model predicts we wind up with a 84-78 record, which is 2 wins above the PWE.

Discussion

The current model is placing a great amount of worth on the ability of PrOPS and xFIP to accurately predict future performance. In addition, the new coefficients are assumed to remain constant. Finally, expecting the current rotation to remain as the final rotation is, again, quite a weak assumption. Anyway, things look a lot brighter for the O's than it did a few months back.

24-Sided Die Determines Season

Batting performance is often simplified by people new to sabermetrics as OPS. Others take that a step further and define things by OBP and SLG. These numbers are used to describe the worth of a batter generically. They fail to recognize that batting position also plays a part in run production. Certain skills are often put to better use in certain positions. A simple analysis of this was done by Cyril Morong. He used raw data from 1988-2002 and determined the value of OBP and SLG by position in the batting order. It should be noted though that OBP and SLG are also rather generic, but it is the best data I have. Of course, hit-derived OBP is worth more than walk derived OBP except in extreme chances. Anyway, from these numbers we can determine how well the Orioles are likely to do based on their lineup and projections from ZiPS.

Assumptions
1. The starting nine players will play every inning of the entire season.
2. The starting pitchers will remain the starting pitchers over the course of the season and average 6 innings per start, equally.
3. The bullpen will be league average.
These are rather prominent assumptions, but I frankly do not care to go deeper into it.

We will compare two lineups. The most common one employed by Trembley along with the ideal lineup based on Morong's formula. Each lineup will be compared to the runs expected in the pitching performance. The run tallies will be converted into wins and losses by the pythagorean theorem.

Results

Pitching
ZiPS is not high on the Orioles pitching and assigns ERAs to them as such: Loewen 4.55, Cabrera 4.85, Guthrie 4.84, Traschel 5.20, and Burress 6.12. With each averaging 194.1 IP at an ERA of 5.11 and a bullpen with a 4.35 ERA, the team will give up 4.86 runs per game. That comes to 787 runs. I am ignoring unearned runs, which makes this an optimistic projection.

Trembley's Lineup
Trembley's typical lineup so far has been Roberts, Mora, Markakis, Millar, Huff, Scott, R Hernandez, Jones, and L Hernandez. This lineup should be weak with regard to underutilizing the top of the order by have Luis Hernandez bat last as well as having Millar and his lack of power in the 4 hole. This lineup is predicted to average 4.86 runs per game and a total of 788 runs scored. That results in a record of 81-81.

Ideal Lineup
The ideal lineup as defined by Morong's formula would be Roberts, Markakis, Huff, Jones, Scott, R Hernandez, Mora, L Hernandez, and Millar. Millar bats last to take advantage of his OBP as well as lessening the damage from his projected lack of power. This lineup brings in a predicted 5.07 runs per game and a total of 821 runs. This results in a 84-78 record.

Discussion
I'm not sure this exercise accomplished much, but it does kind of show what can be expected if many things broke our way offensively. It is likely that any backups to our starters would result in a significant decrease in offensive production (oh, wait, Luis, I didn't mean your projected offense). So, in a way . . . this projection should cover the event that several players outperform their expected production level. In a conservative sense, I would probably decrease offensive production by about 10% to account for days our main offensive players take off. Doing that would result in a Trembley lineup record of 71-91. This looks pretty accurate based on what most projection systems use with playing time considered.

I think the best case scenario would be if the offense improves 10% of what should be expected (787 runs) and the pitching improves 10% of what is expected (720 runs). In this scenario we would have an 88-74 record. I think expecting anything more than that would be tragically optimistic. I think to expect 88 wins is tragically optimistic. Probably expecting 81 wins would be inadvisable. Anyway, that is that. On the flip side, 10% decreased performance on each side would result in a 58-104 record. Expecting anything close to that would also be inadvisable.

Further Reading
Frost King Baseball did a quick study back in mid-March, apparently. It is a slightly more optimistic appraisal of the Orioles offense. The site uses a standard base runs method to determine runs scored.

3 . . . 2 . . . and . . . We are back.

Ok, I have been thinking about resurrecting this blog. I will probably go in a little bit different of a direction and maybe not be as regular in terms of posting.

First Week Thoughts . . . Orioles 4-1

The Orioles have been able to take advantage of weak schedules and good luck in the past few years. I have not done any research on this, but it seems we tend to have a pretty uneven schedule. The Rays and Mariners qualify as such.

The Rays are a largely unproven team with great upside. Commentators have been lauding the Rays for years and it finally seems like it might be coming together. Andrew Freidman is an amazing GM who knows how to do the little things. His pickup of Carlos Pena (of which he and I were the only ones who liked this kid) and several minor moves have strengthened the team in a cheap and efficient manner. His offseason deal to improve his rotation and infield defense may come with a steep cost if Delmon Young figures out what a strike zone actually is or develops his contact rate on par with Vlad. Often focused on money, as pretty much all teams are, they sent Evan Longoria down to AAA. The intent is to strangle in another arbitration year as he is ready for the show. This will cost the team a win or two, which is not really significant as they should finish the season in the realm of .500. 2010 is their season. Still, they are not a strong team, so taking a game isn't big news. It sure is an accomplishment, but we really need to recognize that the O's just are not a strong team this season.

The Mariners are a team that everyone wants to win. People love this team and remark how they pulled together in the face of great adversity and won 88 games. They did two unlikely things: they busted their composite projected record (76 predicted wins) and they busted their pythagorean runs for and against record (80 predicted wins). About 10% of teams do this. They are just simple outliers. It most likely isn't a skill as teams do not sustain this type of production in consecutive years. Anyway, the projection systems say that the Mariners will win 79 games +/- 6. That isn't a strong team. We just won our third straight against them.

Although the Mariners is not a strong team. Our performance is definately something to celebrate. Our bullpen is solid. Our players have been able to hit in a timely fashion (which may or may not be a skill . . . it certainly is a skill that is not very dependable). On the downside, our starting pitching has been bad. Trashcel somehow manages to go deep pitch-wise into games. I still am not sure how he does it. Hopefully, we can turn him into more prospects at the deadline. I don't trust him. Anyway, he needs to go deeper into games or we will see something similar to last year when Sammy burned out our pen. I think our pen is better this year, but if you have to cover 4 innings everyday. That is going to where your guys out. Loewen is what he has been in the past. He has very high potential, but he needs to get more experience. He may always have control issues though. For the past two years . . . I think him and Cabrera share a lot in common. Guthrie helped out today by going a strong 7.

Hopefully, the Orioles become one of those weird 10% teams that do something completely astonishing. Of course, I am not aware of any team achieving 30 games over their given prediction.