In last Saturday's Arizona Fall League Rising Stars Game, Gerrit Cole gave up 4 hits, 2 home runs and 5 earned runs in .2 innings for an ERA of 67.50 and I was very impressed. What impressed me was not his statistics, but rather that, we got our first batch of Pitch f/x data on Cole and boy did it exceed my already high expectations.

Cole threw only 29 pitches, but my pitch type re-classification found that he threw 5 different pitch types. He threw both  four-seam and two-seam fastballs with average speeds of 98 MPH.  He also threw a cut-fastball averaging 92 MPH. He complemented his three fastballs with a change-up and a slider with average speed of 87 MPH and 85 MPH respectively.

Let's look at his average pitch trajectories so far.

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With all the excitement surrounding this year's playoffs, it is easy to forget that The Arizona Fall League is in full swing and it features the first two picks in this years draft, Gerrit Cole and Danny Hultzen. Two of the six team's stadiums are also equipped with Pitch f/x cameras, allowing for us to take a closer look at these future stars. I had originally intended to focus on Gerrit Cole and Danny Hultzen, unfortunately for this analysis' sake, Cole has yet to pitch in one of the stadiums equipped with Pitch f/x, so we'll focus on Hultzen,

Dannny Hutzen was drafted out of the University of Virginia by the Seattle Mariners with the 2nd overall pick in this year's draft and is currently pitching for the Peoria Javelinas. Below is a video of Hultzen warming up at a Fall League game, notice the hitch in his wind-up and his unique delivery which allows him to keep the ball out of the batter's line of sight longer than the average pitcher.

While Hultzen has not logged enough innings to get anything meaningful from his statistics, we can look at some of the Pitch f/x data collected from his starts to provide some insight. Pitch f/x has captured 163 pitches that Hultzen has thrown over two of his three starts. I re-classified Hultzen's pitches and found that he has been throwing  a four-fastball 46% of the time, a two-seam fastball 28% of the time, a change-up 22% of the time and a slider 2% of the time. Both his fastball average a speed of 92.5 MPH and his slider and change-up both average speeds of 82 MPH.

Let's start by looking at Hultzen's average pitch trajectories for each pitch.

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Two weeks ago, we took a look at what individual pitches in baseball were the luckiest pitches in baseball all year, or rather we looked at the pitches that owed most of their success to outside factors other than the pitcher himself.  We did this by looking at the differences between the expected run values for individual pitches and the actual run values, as often seen on fangraphs (under Pitch Type Run Values).  For more on the failures of run values and the differences between expected and normal run values, see the last article.

Today we're going to look at the opposite: the individual pitches that are the UNluckiest* pitches in baseball.  These are pitches that look mediocre to poor (generally) if you look them up on fangraphs, but really have just been affected by other factors to an extent that their run values and results are really misleading.

*I'm not sure if unluckiest is an actual word, but I like it, so there.

Obvious note:  I'm calling these pitches "unlucky" but of course it's totally possible that something about these pitches is really causing these worse results.  But it's far more likely in most cases that these pitches are suffering the worst effects of random variation.

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Hopefully Sergio Romo gets off the DL soon, because he is incredibly fun to watch.  Though Brian Wilson’s popularity might have you thinking otherwise, Romo is the original bearded reliever on the Giants.  He’s also the best reliever on the Giants.  He has an xFIP of 1.64, which would be lowest in the majors if his 37 ⅔ innings made the service time criterion.  His game is getting a ton of strikeouts while keeping his walks low - this year, he’s averaging over 12 and a half strikeouts per 9 innings while walking under ONE.  Unfortunately, he’s been sidelined recently with an arm injury that isn’t supposed to be too serious; he hasn’t thrown in a game since August 9th.  

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Pitch Type Run Values, as found on Fangraphs (using BIS classifications) and other locations, attempt to use linear weights to determine how good, or how bad, specific pitches are during each season for individual pitchers.  Fooling around with these measures on fangraphs can tell us who has the best fastball, change-up, etc and can let us know when we should (seemingly) be angry with our favorite pitchers' choice of pitches during certain individual games. Thus these values can easily lead to arguments where someone argues Pitcher A should use Pitch Type 1 more often at the expense of Pitch Type 2 to get better results.

However, these run values have numerous problems when used in this way: 
First, the results of each individual pitch type is NOT independent of the results/specifics of other pitches a pitcher can throw; in other words, a pitcher's curveball's results are to some extent affected by the results and properties of the same pitcher's fastball (and other pitches).  Thus run values can't tell whether a pitcher would be better off using certain pitches more often and others less - a pitcher reducing the use of his worst pitches could lead to that same pitchers' other "better" pitches getting worse results. 

Second, pitch type run values are heavily dependent upon the count in which pitches are thrown - strikes on 0-2 counts have a naturally higher value than on 3-0 counts, for example.  So if a pitcher throws Pitch A in early counts, or counts where he's behind (say, a fastball), and throws Pitch B (say, a curveball) only when he's ahead or on 2 strike counts, Pitch B is almost certainly likely to look better with run values, even though the pitch may in fact be worse than Pitch A without context. 

Third, and perhaps most importantly, pitch type run values do not attempt to correct for luck or defense.  If a pitcher gives up 8 line drives off of a pitch and all are right at a fielder, the run values indicate that the pitch is really a great pitch (it got all 8 balls in play out!) even though we wouldn't expect this performance to necessarily continue.  The end result of this is that the run values you see on fangraphs may tell you that a pitch is good, only for the reality to be that the pitch is just REALLY lucky (or the converse is true). 

Now it's easy for people these days to make a guesstimate as to how "lucky" or "unlucky" a pitcher overall has been during the year, whether by looking at BABIP, LOB%, or just comparing pitchers' ERAs to more advanced ERA estimators (Whether these things actually tell us exactly how much of a pitcher's ERA this year is due to luck is another question, but they do give a decent indication of one way or the other).  However, nowhere is there a metric easily listed (on fangraphs or something else) that can show the amount luck/defense has affected an individual pitch's results during a given year. 

EXPECTED RUN VALUES attempt to do just that: strip away the results of luck and defense from pitch type run values so that the only thing remains is a true evaluation of how good a pitch's results have been.*

*Feel free to ignore the next two paragraphs if you don't care how Expected Run Values work.

Expected Run Values are the same as regular run values for pitches that aren't put into play (Called Strikes, Called Balls, Foul Balls, Hit by Pitches, etc.).  However instead of using the actual results of pitches put into play, Expected Run Values simply assume that each ball hit into play has an average result based upon the batted ball type of the ball in play. 

In other words: if Expected Run Values see that a ball in play is a ground ball, it calculates the result of that individual pitch as if it was an average ground ball.  The same is true of line drives, fly balls, and pop-ups.  So if a pitcher's in play results are all pop-ups, they'll result in really good Expected Run Values, whereas if they're all line drives, his Expected Run Values will be terrible.

Using this metric, we can look at who has the luckiest pitches in baseball so far in 2011.  After the jump we'll do exactly that.

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The Red Sox are setting the pace in the AL East with their dynamic offense, and the Yankees are sitting pretty closely behind.  With the second best record in the league, the Yankees currently are looking pretty strong in the league's wildcard chase.  

As anticipated, their pitching staff his being headed by ace CC Sabathia, who is currently leading all major league pitchers in WAR.  But the man who has arguably been their second-best starter has been a huge surprise, as he was signed purely as a depth move after not pitching in the majors at all during 2010.  Bartolo Colon has been excellent for the Yankees this year.  A big part of this is that his strikeout rate is the highest it's been since 2000 (!), and his walk rate is lower than his 13-year career average.  He's taking an unusual pitching approach this year, so looking into his PITCHf/x data can give us some more insight on what Colon is doing.