If a player gets Lasik and his vision improves, there would be improvement but it would not be a hot streak. If his vision gets worse (hello Jim Rice) he would stop hitting; again, not a cold streak. If his pitch recognition improves, it should produce sustained improvement, not a hot streak. Confidence or lack thereof no doubt plays a role, but it is likely an extremely tiny one statistically. The pressure of a clutch situation, for example, has been shown to have virtually no measurable effect for most players. I'd bet the same is true of players who feel they're in a groove.

Reggie Jackson seemed like he thrived in the clutch which had alot more to do with his personality than his hitting.

What does "seemed like he thrived in the clutch" mean exactly?  And exactly what defines a clutch situation?

If you can define these things specifically, all the data exists to study what you're interested in.  But I gotta say that there have been an awful lof of smart people looking for 30 years of evidence of "clutch ability" and "streakiness."  As far as I know, every single one of these attempts has resulted either in (a) we can't find evidence of any such thing or (b) the evidence that such a thing exists is so small as to be almost negligible.

Jackson had some monster post-season series.  Also some putrid ones.  Check out: 1973 ALCS, 1974 ALCS, 1977 ALCS (when he wasn't even in the starting lineup for game 5), 1980 ALCS, 1981 ALCS, 1982 ALCS, etc.  His career performance in the late innings of close games (from www.baseball-reference.com) was below his overall performance in terms of batting average, on base percentage, and slugging percentage.  If he had a unique ability to "turn it on" in the clutch, you would not expect that outcome.

I have to agree with contrarian23 on this, and I used to belong to the opposite school of thought.  I still have a certain warm glow in my heart when Derek Jeter comes to the plate in the ninth inning of a close game, but I have read enough thinking from Bill James and other students of baseball to believe that clutch hitting really is a myth.  For every one of Reggie Jackson's Mr. October performances that we all remember, there are a dozen other far more mediocre or routine performances that we don't remember for precisely that reason.  And although we may all think about clutch homers from Bobby Thomson, Bill Mazeroski, Kirk Gibson and others, we simply don't remember the clutch games in which they didn't deliver because their exploits (or lack of them) weren't as well publicized.

Students of baseball have found that baseball players have certain fundamental levels of skill, and it simply isn't possible to elevate these basic skill levels in clutch situations.  A .300 hitter will always be a .300 hitter, give or take, clutch situation or not.  Some hitters may focus a little better in the more intensely competitive situations, but the pitchers and fielders facing them are doing the same thing, so it tends to even out.

Someone here on the forum (it may have been contrarian23) had a really good comment about a year ago that I still remember.  It was something like "show me a guy who hits really well in the clutch and I'll show you a guy who isn't paying attention the other 95 percent of the time." 

Thanks for both of the replies and I understand your school of thought.  All of this is very interesting.  I still believe there is a factor which goes beyond the numbers, beyond the skill, and something that simulation baseball will not be able to grasp.  The managers managing, the will of the players, the doing it for your teamates..Jacksons first year with the Yanks where he hit the 3 homers against LA in the World Series I cannot say was luck or talent. It was the will of a player that wanted to win maybe even for loves sake?  Maybe it was the Angels in the Outfield that helped him? =)

 If thunder was a pitcher and on the mound would you rather face a Yastremski that has gone 5 for his last 25 or a Yastremski that has gone 15 for his last 25.  Maybe it all depends what going on in the pitchers mind. Some pitchers may not care, some may be as nervous as can be but whether you get him out or not, the stats are in the back of your mind at some point.

You can tie yourself into knots with this stuff....someone (either earlier in this thread or in another recent thread) asked - essentially - if the "5 for 25" Yastrzemski was "due."  In other words, since he had recently performed below expectations, was he now supposed to perform above expectations in order for "it all to even out."  So should we expect the 15 for 25 Yaz to overperform because he's on a hot streak, or underperform because he's due to come back to earth?  Or do all those possible extraneous factors - the things "beyond the numbers" more or less even out, and therefore are just not worth worrying about?

I want to make sure I don't leave the wrong impression - I don't think players are machines just spitting out random stats.  Players are human beings with an amazing collection of physical and mental gifts that put them in the top 0.0000000001% or so of the population in terms of baseball playing ability.  I think that if a player had a particular mental weakness that left him unable to perform at the peak of his abilities in pressure situations that he would be weeded out long before he got to the majors.  By the time you get to MLB, you are dealing with the cream of the crop in terms of the mental and physical skills needed to play baseball,

There are no doubt lots of factors that impact each individual plate appearance beyond what a simulation will be able to capture.  Many of them physical, many of them mental.  What I believe is that virtually all of the time the balance of those factors - some working in favor of the hitter, some working against him - pretty much net out to be zero, and that the best way to predict or model the probabilities of the outcome of that particular PA is to look just at the raw underlying statistical record of the individuals involved without adjustments for streakiness, clutchness, chemistry, will, or any of the other things that might come into play. 

Thanks contrarian, that is what makes this game pretty fun, is the realisticness of the game.

I was a big time Yankees fan when they signed Reggie, and I gradually rooted less and less for them because of Reggie, George, and Billy's antics during that era. My honest opinion of Reggie is that when he wanted to be, he was as good as any player I have ever seen, and I go back to 1960. He frequently just played like he didn't care, both at bat and in the field. As far as streakiness in the SIM goes, while random chance certainly has an effect, it is also useful to look at the teams you played against when things were going bad, as well as when they start going well.Sometimes, what seems like a hot streak is me playing against guye who are resting players and/or guys who have given up. And, what appears as underperformance is me playing against better teams, playing to win.

Posted by thunder1008 on 7/18/2010 8:48:00 PM (view original):
I have to agree with contrarian23 on this, and I used to belong to the opposite school of thought.  I still have a certain warm glow in my heart when Derek Jeter comes to the plate in the ninth inning of a close game, but I have read enough thinking from Bill James and other students of baseball to believe that clutch hitting really is a myth.  For every one of Reggie Jackson's Mr. October performances that we all remember, there are a dozen other far more mediocre or routine performances that we don't remember for precisely that reason.  And although we may all think about clutch homers from Bobby Thomson, Bill Mazeroski, Kirk Gibson and others, we simply don't remember the clutch games in which they didn't deliver because their exploits (or lack of them) weren't as well publicized.

Students of baseball have found that baseball players have certain fundamental levels of skill, and it simply isn't possible to elevate these basic skill levels in clutch situations.  A .300 hitter will always be a .300 hitter, give or take, clutch situation or not.  Some hitters may focus a little better in the more intensely competitive situations, but the pitchers and fielders facing them are doing the same thing, so it tends to even out.

Someone here on the forum (it may have been contrarian23) had a really good comment about a year ago that I still remember.  It was something like "show me a guy who hits really well in the clutch and I'll show you a guy who isn't paying attention the other 95 percent of the time." 

I saw a story years ago where Reggie said nobody questions it when Jack Nicklaus is winning major championships, and I think there is some point to that.  Some guys are better able to control themselves when the adrenaline is pumping, and some aren't.

The statistical analysis of it is ridiculous because NO player [not even Bernie Williams and Derek Jeter] will ever compile enough "clutch" at-bats to provide a meaningful statistical sample.  You can spin that any way you want.

Jeter has more postseason AB's than anybody in history -- almost a full season's worth -- and his stat line is eerily reminiscent of one of his regular seasons.  BUT, he compiled those postseason stats against the top three teams in each league.

One other point that I haven't seen mentioned. Early on, no one is experiencing fatigue, due to DAMP among other things. So early on, teams that are going to be unsuccessful in the long run, may be competitive until fatigue begins to take its toll. I would also venture that poor teams get less attention from their owners the further into the season they go. This might cause a team to start slow out of the gate, but pick up steam as the season wears on.