The post below discusses the hot hand, in reference to the amazing LCS and World Series performance by the World Champion(!) Boston Red Sox. I take the point that the general public, and television commentators in particular, often refer to "hot" or "cold" streaks in the midst of purely random sequences of events. And detecting systematic departures from a random walk model of basketball shooting or baseball hitting is notoriously difficult.
But these facts do not disprove the existence of streaky performance. Many factors - some physical, some psychological - affect an athlete's ability to perform. Take a golfer with a bad back. When it hurts, he's toast. When it's fine, he's as smooth as silk. Think Freddie Couples. Better yet, on the psychological side, read Malcolm Gladwell:
There was a moment, in the third and deciding set of the 1993 Wimbledon final, when Jana Novotna seemed invincible. She was leading 4-1 and serving at 40-30, meaning that she was one point from winning the game, and just five points from the most coveted championship in tennis. She had just hit a backhand to her opponent, Steffi Graf, that skimmed the net and landed so abruptly on the far side of the court that Graf could only watch, in flat- footed frustration. The stands at Center Court were packed. The Duke and Duchess of Kent were in their customary place in the royal box. Novotna was in white, poised and confident, her blond hair held back with a headband--and then something happened. She served the ball straight into the net. She stopped and steadied herself for the second serve--the toss, the arch of the back--but this time it was worse. Her swing seemed halfhearted, all arm and no legs and torso. Double fault. On the next point, she was slow to react to a high shot by Graf, and badly missed on a forehand volley. At game point, she hit an overhead straight into the net. Instead of 5-1, it was now 4-2. Graf to serve: an easy victory, 4-3. Novotna to serve. She wasn't tossing the ball high enough. Her head was down. Her movements had slowed markedly. She double-faulted once, twice, three times. Pulled wide by a Graf forehand, Novotna inexplicably hit a low, flat shot directly at Graf, instead of a high crosscourt forehand that would have given her time to get back into position: 4-4. Did she suddenly realize how terrifyingly close she was to victory? Did she remember that she had never won a major tournament before? Did she look across the net and see Steffi Graf--Steffi Graf!--the greatest player of her generation?
I remember that match. If you don't believe in the hot hand, you'd believe that Novotna had a decent chance of winning it at that point. It didn't turn out that way.
Being a cynic, I used to scoff when announcers would talk about shifting "momentum" in a football game. Not any more. Sure, they overuse the term, but don't they do that with everything they chatter about?
And by the way, the Astros got "hot" this season too, and I'm mighty grateful for it.