Momentum in sports is a myth, professor says

Philadelphia, PA — As the 2000 Major League Baseball season unfolds, baseball fans from all 30 major league cities hold hope that their team can catch a wave of momentum and ride it to that final World Series victory on a crisp October night. But one Penn State Great Valley professor claims that momentum might be nothing more than manmade hype.

"Momentum does not appear to be a causal factor in winning or losing streaks," said management professor Roger Vergin. "Winning in baseball and other sports is not simply a random event. They (professional sports) are games of skill, and the better teams win more often than the inferior teams. But, even though the teams go on occasional long winning streaks, such streaks are no longer or more frequent than would occur by chance, given the overall strengths of the teams."

Vergin based his findings -- to be published in the June issue of the Journal of Sport Behavior -- on his personal study of all games during the 1996 Major League Baseball season, all National Basketball Association games over two seasons, and previous studies of professional sports conducted by researchers.

In the study, he said the concept of momentum could be a convenient way to explain winning and losing streaks, but that it offers no more credence in this regard than dumb luck.

In his research of the 1996 Major League Baseball season, Vergin examined different statistical categories that he believed could prove or disprove momentum. In each case, the number and length or streaks were almost identical to what would have occurred if the probability of winning or losing the next game was independent of the results of winning or losing the previous games.

"In other words, a team is just as likely to win its next game if it has won its last five in a row or lost its last five," he said.

For example, there were 1,112 winning streaks of one to 12 games in length during the 1996 season, but there was an expectation of 1,116 streaks under the random-chance scenario. On the losing note, there were 1,112 losing streaks, with 1,115 projected by chance.

In another example, there were 72 winning or losing streaks of four games projected by chance and 72 actually occurred; there were 36 winning or losing streaks of five games projected by chance and 38 actually occurred. Streaks in the NBA were equally close to those projected by chance.

Vergin also noted in his study that previous research of NBA basketball done by Gilovich, Vallone and Tversky in 1985 seems to refute the concept of momentum with regard to getting a "hot shooting hand."

"They found that there is no hot hand in basketball. The outcome of successive shots is approximately independent," said Vergin. "Actually, outcomes were slightly negatively correlated -- a player was more likely to make the next shot after missing a shot."

So why does the notion of momentum tend to hang around?

When a team goes through a winning or losing streak of monstrous proportions, it tends to stick in people's minds for a while and further the momentum myth, said Vergin, who used his local baseball team as proof.

"In Philadelphia, whenever a local professional team loses a few games in a row, people bring up the 10-game losing streak of the Philadelphia Phillies at the end of the 1964 season, which cost them the pennant," he said. "All of the thousands of games in the 30-plus intervening years of 'win a few, lose a few' are ignored, because they are so usual."

Press Contact: David Jwanier, manager of public information for Penn State/Philadelphia Region, at (610) 648-3276.