I'm sure this has never happened to you. The other day I was interviewing a computer scientist from California. I was asking several insightful, thought-provoking questions, or so it seemed, and suddenly he got a far-off look in his eye. He stopped cold, as if he had made some dramatic, interesting discovery, and he said, "Has anyone ever told you that you are a dead ringer for Mayor Ed Koch of New York?"

"Well, no," I said, "No one ever has.""It's remarkable," he said, and then as if making one vain attempt to rescue my bruised ego, "Oh, you're a lot better looking than he is! But it's a remarkable resemblance just the same."

It really was the first time I had been compared to Ed Koch, and regardless of his looks, I wasn't crazy about being thought of in the same breath as someone who had used racist tactics in the presidential campaign this year.

I strongly suspect that it was my hairline that looks so hauntingly like that of Ed Koch. But it is hardly the first time I have been told I look exactly like some famous person. When I was growing up, several people told me that I looked remarkably like Alan Ladd, the movie star, who is now long forgotten by most people. Remember "Shane"? I didn't mind so much, because I still think he is much better looking than Ed Koch.

Not so long ago Marti and I were eating in a restaurant, and the waitress got that look in her eye, and she said excitedly, "Oh, you look EXACTLY like Pam Dawber's father on `Mork and Mindy.' " If you remember him, his face is OK - nothing like Ed Koch's - but he is slick bald. I'm pretty sure I have more hair than that.

Cynically, I asked, "So if I look like Pam Dawber's father, who does my wife look like?" Without missing a beat, she said, "Oh, that's easy - she looks like Pam Dawber!"

Great. Now I felt even worse. I looked like my wife's father! Actually, it wasn't a bad comparison. Marti has also been told that she looks like Audrey Hepburn and Natalie Wood - and other glamorous movie actresses who I have momentarily forgotten. Sometimes it is a glamorous singer she resembles. I've never minded those comparisons because they seemed to validate my preference in women.

When I was growing up, my older brother had a thick head of hair and a "widow's peak," causing several people to say with great sincerity that he resembled Clark Gable. I tried not to let that bother me, but I desperately wanted to look like Tyrone Power. Predictably, no one ever accused me of such a resemblance; after all, my brother looked like him, too.

When I reached that dreaded age when my arms were not long enough for me to read successfully, and finally got some reading glasses - the ones that perch precariously on the end of the nose - then people thought I had a remarkable resemblance to Benjamin Franklin.

Actually, my favorite look-alike is comedian Bob Newhart, the guy with the button-down mind. In the last few years, several people, including a close friend of mine, have sworn to an uncanny resemblance between the two of us. Some even see a fascinating connection between my allegedly wry sense of humor and Newhart's. I always humbly deny these claims, of course, but down deep, I don't mind.

Then there are those people that I hardly know who unaccountably swear that I look exactly like some relative or close friend of theirs, someone I have never met. "It's amazing," they say. In those cases, I am always grateful that I have no image to call to mind.

If I could choose the people I look like there would be no problem. Or if I really DID look exactly like one certain person and everyone said it, I could get used to it.

Instead, I have to live in fear that tomorrow someone will say, "Wow, if you had a birthmark you would be the spittin' image of Gorbachev!" Or "You look JUST LIKE that little weasley guy with Andre the Giant in "The Princess Bride."

As I said - this probably never happens to you.