TV viewers may soon be bombarded with two runs of the same episode of their favorite network primetime series in the same week.

The Big Three and Fox won’t be double-running these hit series as a public service: it’s simply a bottom-line response to a clever ploy by the upstart United Paramount Network.

In a calculated move, UPN has persuaded Nielsen to allow it to add together – or cume – the ratings of the first and second runs of the same episode of the new “Star Trek: Voyager” as a way to extract premium rates from advertisers.

“Nielsen may have opened up a Pandora’s Box,” said a high-ranking industry executive, indicating the real possibility that all the networks will start experimenting with reruns of their most popular series on their weakest nights as a year-round scheduling strategy.

Already, the networks frequently shore up busted time periods with reruns of everything from “Home Improvement” and “Mad About You” to the “X-Files” and “The Simpsons.” But these don’t fit the “Voyager” model because they are different episodes and are sold to advertisers separately.

Tony Malara, president of affiliate relations for CBS, said he and David Poltrack, the Network’s head of research, firmly opposed Nielsen’s allowing United Paramount to cume its ratings of “Voyager,” a practice that the Hollywood major perfected in the selling of the syndicated “Trek” sequels, “The Next Generation” and “Deep Space Nine.”

The advantages to the Big Three and Fox of following Paramount’s lead are that they could chalk up bigger advertising dollars, harvest better ratings on their worst performing nights and possibly pare down development budgets, the latter because the reruns would replace a revolving door of new series that flop. The webs, however, could have difficulty convincing suppliers of hit sitcoms to allow as many as four runs of each episode in a given season. Although the suppliers would pocket more cash in network license fees from the extra runs, the added revenue might not offset the possible diminished value of the sitcom in off-network syndication. Stations would likely balk at ponying up big bucks for a sitcom that would be getting double the usual number of runs in network primetime.

In contrast, high-rated primetime hours like “ER” and “NYPD Blue,” which tend to bypass the station market for lower-paying cable networks, would be more likely candidates for “Voyager”-like double runs. For producers of new series, the extended use of same-week reruns could prove to be a serious hardship because they would occupy valuable primetime real estate.

Brian Fiori, VP of research for UPN, downplays the concern of the networks. He says the Big Three and Fox were never precluded from using the double-run strategy to increase their advertising revenue.

Paramount’s considerable success in boosting the ad rates in the Star Trek sequels in syndication may not carry over into the network arena, however.

A show that harvests a 22 rating would generate more advertising revenue than one that earns a combined 16 and 6 rating on two separate nights, said Jerry Dominus, the head media buyer for the J. Walter Thompson ad agency. “It’s the audience power of a one-shot day-and-date Nielsen-ratings-grabber,” he said, “that’s the most desirable buy on Madison Avenue.”

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