09 February 2011

Vladimir Guerrero's Whiff Rate

Note: Be sure to check out the last post on Vlad here.

This is just a short post today and, to be up front, I do not know what it means.  As you know I like to dabble in pitch f/x and I was interested in whether there was a way to visualize what I have thought I have seen and what others have seen: Vlad's bat is slowing down.  Now, this may seem like I am piling up on him, but I am not.  My thoughts on the signing generated a lot of interest and that has sustained my interest somewhat.

The graph below shows Vlad's whiff rate when four seam fastballs, curve balls, change ups, and sliders are thrown.  What we see is that he has stayed on top of fastballs at about a 8.4% whiff rate.  However, this is in contrast to the other offerings where he has progressively shown a tendency to swing and miss.  The upward trend with the curve balls is the effect of multiple data points.  Sliders and changeups appear to be largely affected by his whiff rate last year.

What does this mean?

I don't know.  You could say that in order to maintain his hitting ability he cheats on the fastballs and is taken advantage by other pitches, but I don't think this single graph shows that.  I would want to see more data points from other years, which is not something that is available.  I'll try to think of some ideas to answer these questions and post at some point about what I eventually come up with.


Tim Anderson said...

What about that pictures have learned how to pitch to him?

Crawdaddy said...

Well, that would be part of it. As a batter ages and his swing slows down, pitchers will start to recognize this and take advantage of it. It is not entirely uncommon to see a batter have a last hurrah by cheating on certain pitches until pitchers catch on to what is happening.

Tim Anderson said...

What about these numbers?

Vlad had a 79% contact percentage in 2010. 80% in 2009. His average for his career? 80% which is also the MLB average. In fact, his contact percentage has increased. From 1996-2003, his percentage was 79%. From 2004 to now, it has been 81%.

Crawdaddy said...

How can contact rate stay the same, but whiff rate increase on certain pitches?

Maybe he is swinging at fastballs more often and refraining from swinging on offspeed pitches, where he has trouble. By changing the sub-section of pitches, he may be able to maintain contact rate.

I don't really know. I need to look more into it.

Tim Anderson said...

He hit .316 against finesse pitchers in 2010.

Crawdaddy said...

Look what these stats are meaning.

Finesse are in the bottom third of the league in strikeouts plus walks.

Do you really think that is a very useful statistic?

Crawdaddy said...

One things to remember for other posters...I am pretty familiar with most statistics used in baseball and where they can be found. I've created new stats, re-engined ones, and read a variety of sources . . . so I typically know what someone is talking about when they mention one. however, some of these are pretty obscure. In that case, it is good to cite it. Plus, if it is the first time you come into contact with a stat . . . learn how it is calculated and whether it is indeed a useful one.

Anonymous said...

This data means nothing. The R-values are low for a three-point plot. There is no way that you can expect this trending to be accurate through 2011.

Crawdaddy said...

As I wrote, for two of the lines it is being pushed solely by the last season.

Does this mean they mean nothing? No, that is a bit too absolute. It may or may not mean anything, as I have indicated. There needs to be more corroborating evidence to make any conclusion out of this. However, this piece could be useful in conjunction with other metrics.

What those are, I do not know.

I'm not sure why there is such a need to be so definitive in whether something means something or not. This is part of science where we have few data points and wonder if there is a way to shoehorn something out of it. This is often fraught with error as I think Malcolm Gladwell's blink inadvertantly shows, but I think it is a bit much to conclude something means nothing.