Yesterday I continued new xK% equation week by discussing the 10 pitchers that have overperformed and underperformed the metric the most since 2011. While I calculated the group averages, pulled in fastball velocity, and most frequently used secondary pitch, the sample size was far too tiny to conclude anything. So at the request of commenter JUICEMANE, I have decided to do a larger study in an attempt to explain why some pitchers consistently over- or underperform the xK% equation. Do the players within each group on either side have anything in common with their groupmates?

Read the rest of this entry »

Yesterday I rolled out an updated version of my pitcher xK% equation, which estimates what a pitcher’s strikeout rate “should be” given various strike and strike type metrics found at Baseball-Reference.com. With my data set, I put together a table calculating historical averages during the time period (2011-2016) I compiled data for. I’ll share the top 10 pitchers that have outperformed and underperformed their xK% (so if a pitcher outperformed by 2% in 2011 and 3% in 2012, I’ll be looking at the total of 5%, rather than the average of 2.5%), and we’ll try to figure out what, if anything, the pitchers in each group have in common with each other. So let the fun begin!

Read the rest of this entry »

The best equation I have ever developed from an adjusted R-squared perspective is pitcher xK%. That equation yielded a 0.913 R-squared, so it didn’t exactly need any tweaking. However, I was on an xEquation rush recently and decided to develop new ones, as well as update old ones. So we’ll begin with xK% and dedicate my week’s posts to looking at the new version of the metric.

Read the rest of this entry »

Don’t you love it when a player’s name makes it super simple to create an absolutely brilliant title? I do! So yesterday, the Mariners continued their fantasy league moves by acquiring 27-year-old southpaw Drew Smyly. Up until 2016, Smyly enjoyed a fantastic beginning to his career, as he owned a 3.24 ERA/3.43 SIERA between the starting rotation and bullpen. But shoulder injuries hit in 2015 and he becaome afflicted with a severe bout of gopheritis during this past season. His ERA ballooned to 4.88 as his strikeout rate fell and he allowed the second highest fly ball rate in baseball among qualified pitchers. Now he moves to Seattle, where perhaps a change of scenery could do him some good. Will he benefit from the park switch? Let’s find out if such a possibility exists.

Read the rest of this entry »

In his ninth season, Colby Rasmus is set to join his fourth team, as he heads from one warm climate to another. But despite the fact he’ll be switching home parks, he’s still going to be playing in an orange juice box. On Monday, it was reported that he agreed to a one year contract with the Rays. Coming out of Houston, the knee-jerk reaction is that his fantasy potential, whatever there was left of it, is now kaput. But is that really true? Let’s bring on the park factors to find out what a move from playing half his games in Minute Maid Park (MM, Houston) to Tropicana Field (Tampa, errrr, St. Petersburg) may do to his performance.

Read the rest of this entry »

So just as I had hoped when I published my 2017 starting pitcher strikeout rate upsiders using my xK% equation, followed by my recap of my 2016 upsiders, it generated some excellent discussion. I made mention in my recap article, that was also requested in the comments, that I should also compare how xK% did versus the 2016 Steamer projections. It’s not enough to share a list of 12 guys with upside, show that as a group they did improve, with 66% doing so, and call xK% successful. If every forecasting system projected improvement as well without my xK% equation, then perhaps the equation isn’t providing any incremental value. So let’s bring my recap table back, but this time with the 2016 Steamer projections included.

Read the rest of this entry »

So on Thursday, I used my xK% equation (updated version coming soon! probably) to assemble a list of starting pitchers that possess strikeout rate upside this year, strictly based on their strike percentage, looking, swinging, and foul strike rates. In it, I hinted that maybe I’ll recap how my 2016 pitcher list performed and since the majority of the comments requested such a post, here it is! Remember that the list assumes no change in pitch mix, strike percentage, or strike type rates. Essentially it’s saying that if the pitcher keeps doing the same thing, his strikeout rate should improve simply based on better sequencing or fortune.

Read the rest of this entry »

Three years ago, I shared with you an updated version of my xK% equation. The formula uses a trio of strike type rates found at Baseball-Reference.com, including a pitcher’s looking, swinging, and foul strike percentages, along with his overall rate of strikes thrown. With an adjusted R-squared of 0.913, it explains a very high percentage of a pitcher’s strikeout rate. Its best use is early in the season when the plate appearance (the K% denominator) sample size is still small, as xK% uses total pitches as the denominator, so we can reach a reasonable sample size to analyze much more quickly.

Read the rest of this entry »

Yesterday, I discussed the fantasy relevant average fly ball and line drive exit velocity (EV) surgers, which overwhelming fueled a spike in HR/FB rate. Let’s now check in on the other side of the ledger — those hitters whose EV declined precipitously from 2015 to 2016.

Read the rest of this entry »

We officially have two seasons worth of Statcast data! Mind you, it’s not two full seasons, nor does it include every batted ball. But it’s still highly useful data. Although I continue to work on developing new equations with the data, we could all agree on one thing — harder hit balls are better. This is especially true when considering fly balls and line drives. We care far more about this bucket of batted balls than grounders because I have calculated a correlation of 0.769 between average fly ball and line drive exit velocity (EV) and HR/FB rate. So let’s find out which fantasy relevant hitters enjoyed EV surges from 2015 to 2016 and if those spikes resulted in HR/FB rate increases as well.

Read the rest of this entry »