BALTIMORE, NOV. 26 -- A Bethesda man who is a former employee of the Arbitron television rating service was sentenced to five years' probation today for pirating confidential equipment and documents from Arbitron and anonymously giving them to Arbitron's chief competitor, A.C. Nielsen Co.

U.S. District Judge William M. Nickerson brushed aside a prosecutor's recommendation that Barry David Glick be imprisoned for at least 27 months. He imposed the probationary sentence after agreeing with a psychiatrist that Glick has a personality disorder that "significantly reduced his mental capacity" and contributed to his criminal actions.

Prosecutor Dale P. Kelberman said his office is considering an appeal of the sentence.

Glick, 45, pleaded guilty Sept. 6 to a single count of interstate transportation of stolen property.

A former employee in Arbitron's meter operations division in Laurel, Glick was charged with anonymously mailing confidential memos and a high-tech TV monitoring device to Nielsen early this year in what prosecutors called a classic industrial espionage case. The materials were valued by prosecutors at $240,000.

The memos, according to prosecutors, described ongoing development of a new Arbitron computerized TV rating system called ScanAmerica that would allow Arbitron for the first time to furnish national television program ratings to TV networks overnight. Only Nielsen has that capacity now, prosecutors said.

Through a series of unsigned letters, Glick hoped to be hired surreptitiously by Nielsen as an "independent consultant" and provide more inside information, prosecutors said. Nielsen attorneys, however, alerted Arbitron officials to the attempted scam, according to prosecutors. The FBI then traced the anonymous letters to Glick, prosecutors said.

At today's sentencing, psychiatrist Jonas R. Rappeport said Glick's personality disorder resulted at least in part from a traumatic childhood in which as a latchkey child he was often ignored by his parents.