tag:blogger.com,1999:blog-20149989.post8893092912189254484..comments2024-01-10T16:29:30.043-05:00Comments on Fonzie Forever: The "Decline" of Johan SantanaJames Esattohttp://www.blogger.com/profile/13823705871077609158noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-20149989.post-66921574053132026272010-02-25T16:17:59.514-05:002010-02-25T16:17:59.514-05:00Let me try and distill what I meant in the origina...Let me try and distill what I meant in the original blog.<br /><br />1. It is incorrect (and simplistic) to simply look at a series of numbers trending in one direction and project them to continue upon that trend.<br /><br />Johan Santana, and his peripherals HAVE DECLINED in the last few years. However, it is a mistake to call him, as you do above "a pitcher in decline."<br /><br />2. Those statistics are simply records of what has happened before. His average FB may have been 93 in 2007, 92 in 2008, and 91 in 2009. <br /><br />But there is just as much (or more) reason to believe that his FB for 2010 will be 91 as it will be 90.<br /><br />When a stock is valued at $5, and then $10, and then $15 - that is because at those precise moments in history, that was their value. <br /><br />A stock value, just like a player's inherent ability to throw a baseball, or miss bats, or run a 100 meter dash, does not have its own inherent MOMENTUM.<br /><br />His WHIP has risen six years in a row - that is true. But there is NO evidence to believe that there is ANY reason why his WHIP will be higher in 2010 than it was in 2009.<br /><br />3. Trends are nice to look at, but projecting them to continue is simplistic. It is an excuse to abandon reason - to skip the step of making an honest evaluation of the future. <br /><br />If Santana declines next year, then everyone who projected him to have this continual linear decline will be correct. If he does not decline again, those people will be able to point to the previous mathematical evidence and claim that his improvement was unexpected.<br /><br />That's silly. Like I said above, statistics are not real. <br /><br />4. And this is most important, because I need to clarify and the poster was right in calling me out for this. <br /><br />When I said that stats "carry little or no predictive value for the future," I misspoke. What I meant is that the TREND established by those numbers carry no predictive value in the future. <br /><br />You are what you are, on an objective level, in real life. Santana in 2010 will be Santana in 2010 -- he will not be an echo established by Santana 2003-2009.<br /><br />Projecting for him to decline again is undoubtedly the safer bet because a) he is 31 and b) it is hard for ANY superstar to maintain his level of performance. But as far as I'm concerned, I'd prefer to use my knowledge and make a projection rather than proclaim him to be "in decline"Brian Manganhttps://www.blogger.com/profile/04163919142076839950noreply@blogger.comtag:blogger.com,1999:blog-20149989.post-727321670924429782010-02-25T11:18:18.171-05:002010-02-25T11:18:18.171-05:00Thanks for the comment!
I'm actually mobile a...Thanks for the comment!<br /><br />I'm actually mobile at the moment, but when I get the chance later today or tonight, I will most definitely respond to this. It's a hard concept to articulate properly, so I know I fudged it a little.Brian Manganhttps://www.blogger.com/profile/04163919142076839950noreply@blogger.comtag:blogger.com,1999:blog-20149989.post-26659710303059046142010-02-25T10:19:21.790-05:002010-02-25T10:19:21.790-05:00Seems like you are rationalizing quite a bit here....Seems like you are rationalizing quite a bit here. There is compelling statistical evidence that Santana's skills are on the decline. It is understood that trends such as his declining velocity and increasing contact rate are no guarentee of the future, but these individual trends taken in the aggregate offer, at the very least, compelling evidence of a pitcher in decline. <br /><br />I would also throw in the fact he moved from the AL to the NL and did not show an improvement in performance, the fact that he is coming off arm surgery, and above all else, his age, as additional reasons to expect a decline in performance from Johan. <br /><br />Your argument just wasn't worth making. No one can dispute that apparent statistical trends are often just illusions of normal statistical variation. You have offered no compelling counter-evidence that shows Johan is not declining, you have simply questioned the reliablility of the evidence of his decline, and your reasons for dismissing it preclude us from using statistcal trends to make any conlusions whatsoever. <br /><br /><br />Also, you may want to re-think the following statement:<br /><br />"Sets of numbers -- like a contact rate, or a stock value -- are simply recordings of things that have happened in history. They carry little or no predictive value for the future."<br /><br />Perhaps you could better specify what you meant by this because it seems outrageously broad to me. You also appear to contradict it later in the piece:<br /><br />"the most reliable information that we have tells us that his fastball was 90.5 MPH last year...my money is on his fastball being 90.5 MPH again."<br /><br />How is your method of reasoning any different from the espn writer's? You are both taking a sample of data about the past and making a judgement on what is probable for the future. You use the phrase "my money", which seems equivalent to saying "odds are" or "it is probable", all of which refer to some judgement about a future--understood to be unknowable--using data from the past. So, you have acknowledged, that it is more likely than not that at least some sets of numbers have some predictive value for the future. <br /><br />Yet, if what you said previously is true, and that 90.5 number had "little or no predictive value" on what this year's number will be, why would it be a good idea for you to "put your money" on it being the same?Anonymousnoreply@blogger.com