SAN DIEGO -- To "er" is human.
You may think you are articulate. You may see yourself as socially graceful. Even so, forget about trying to rid the "ums" from your patter.
Each person uses several hundred filled pauses -- "um," "er" and "like" are prime examples -- every day and sometimes as many as 900 an hour, estimates psychologist Nicholas Christenfeld of the University of California at San Diego.
Dr. Christenfeld studies the um phenomenon, which also includes "eh," "well" and "you know." These filled pauses signal a timeout while the speaker grapples for the next word or thought, he said.
It is the verbal equivalent of "bouncing a tennis ball before you serve," said Dr. Christenfeld.
And, based on analysis of speech patterns around the world, the pauses are universal, said Dr. Christenfeld, an assistant professor who claims that he is a man of few ums.
But he is still trying to figure out what he calls the fundamental question: why people utter um, especially because most believe it only makes them sound fuzzy-headed. "Why do people say tTC 'um' instead of sitting quietly -- given that people don't admire people who um?" he asked.
Dr. Christenfeld believes that such utterances signal the individual's desire to speak -- though the actual words may elude the tongue, he said. It is also a sign that the speaker is weighing his verbal options and ideas.
President Bush averages 1.7 ums a minute while Vice President Dan Quayle ums along at only 0.1 a minute.
What does it mean?
"Either Quayle is a masterful speaker, a man of steel or he's not contemplating many options when he speaks," Dr. Christenfeld said. "I pick the latter."
The White House declined to comment.
Dr. Christenfeld has examined the frequency of ums in the banter of several television talk show hosts who, he presumed, got their jobs in part because of their ability to think and speak on their feet.
Johnny Carson utters 1.5 ums per minute; Arsensio Hall, 2.4, and David Letterman, 8.1, according to Dr. Christenfeld. (Pat Sajak, who briefly was host of a talk show, spoke 9.8 ums per minute -- "It's amazing he lasted as long as he did," Dr. Christenfeld said.)
Mr. Carson and Mr. Hall were unavailable to comment.
Mr. Letterman's personal assistant, Laurie Diamond, said: "Here's the thing, um, Dave's in rehearsal."
Dr. Christenfeld believes that Mr. Letterman's rate may be so high because he improvises more than the other talk show hosts.
"David Letterman certainly seems glib and facile," Dr. Christenfeld said. "But Johnny Carson would probably say that experience counts."
For four years now, Dr. Christenfeld has studied "um" and "er" and "uh" -- the topics of his graduate thesis at Columbia University. He has also flirted with "well" and "like," but those are words that have meaning even if people do use them like conversational pepper.
Clearly, Dr. Christenfeld has been won over by ums, which he confided, he usually cannot help counting -- a habit that sometimes makes colleagues and acquaintances self-conscious.
"This is worth studying because it happens so much -- anything that happens 10 times a minute is worth studying," he said.