Nielsen Chastises Oprah Over a Twitter Plea OPRAH WINFREY routinely reminds her nearly nine million followers on Twitter to tune into her one-year-old channel, OWN, and chats along with viewers on premiere nights. Those informal messages create a direct connection between one of the most famous women in the world and her fans. But on Sunday night, when she used that powerful online megaphone to make what seemed to be a simple plea, Ms. Winfrey broke a rule that the Nielsen ratings company rarely has to enforce. "Every 1 who can please turn to OWN especially if u have a Neilsen box," she wrote on Twitter just as a new episode of her interview show, "Oprah's Next Chapter," began. What seemed to most Twitter users to be a simple, if misspelled and desperate-sounding, call to watch a struggling channel was seen by Nielsen as a potentially serious violation of its policy. Nielsen measures the television viewership of a sample of roughly 25,000 households across the United States, and it works hard to ensure that the sample is not coerced to watch specific shows or channels. After officials at OWN and Nielsen corresponded on Monday morning, Ms. Winfrey removed the Twitter post at the ratings company's request. "I intended no harm and apologize for the reference," she said in a statement. In Nielsen's ratings system, an asterisk will be attached to OWN's ratings at the time of day Ms. Winfrey's message was sent, noting a "possible biasing effect," a Nielsen spokesman said. "It is Nielsen's policy to note attempts to single out panel members to either change their viewing habits or otherwise influence or affect their reporting," the spokesman, Matt Anchin, said later in an e-mail. Such attempts are rare, but are taken seriously by Nielsen, since its ratings are used to set advertising rates and determine the success or failure of shows. Television hosts, executives and channel owners - for OWN, Ms. Winfrey is all three - may privately doubt the veracity of the daily ratings, but the TV industry collectively agrees to let them be the currency for buying and selling. So any hint of tampering with the Nielsen household sample sets off alarms. In 1999, when a sports anchor in Baltimore told viewers, "We need you tonight, especially our special viewers, and you know who you are, with that little box on the back of your set," referring to Nielsen's measurement box, Nielsen admonished the station. "Not too proud to beg," The Baltimore Sun said of the case. Last November, the NBC late-night comedian Jimmy Fallon declared that he wanted to "Occupy Nielsen." He told viewers, "This Friday, I want everyone who knows someone who's in a Nielsen family to call "em up" and tell them to turn on his show. "You don't even have to watch the show, you just have to put it on," he said. That Friday, Nielsen excluded Mr. Fallon's show from its averages altogether, a much more severe punishment than the one presented to OWN on Monday. That's because Mr. Fallon's request was more specific than Ms. Winfrey's. On Sunday, Ms. Winfrey's unusually blunt request and the misspelling of the Nielsen name caused some Twitter users to doubt that Ms. Winfrey was the one actually doing the typing. But she was, according to her executive producer, Sheri Salata, who was in the same room at the time. They were together at a hotel in suburban Atlanta that did not carry OWN. The fact that it is difficult for some viewers to find highlights one of the channel's problems. The two were watching the Grammys like tens of millions of others. Five minutes after the post about Nielsen, when the Grammy Awards ran a commercial, Ms. Winfrey wrote, "Grammy people..u can turn to OWN." Some replied to Ms. Winfrey to thank her for the reminder, but others criticized the tone of her two please-tune-in messages. Ms. Winfrey replied to one of the people who labeled her message "desperate" by saying, " "desperate" not ever a part of my vocab." The last year has been a hard slog for Ms. Winfrey, who created her cable channel in a joint venture with Discovery Communications by converting the Discovery Health Channel into OWN in January 2011. Although she cautioned from the start that OWN would need years of nurturing, its early ratings have been disappointing to people involved in the venture. Nearly a dozen advertisers made big multiyear commitments in advance of the channel's debut, and to them - as to investors and reporters - Discovery and Ms. Winfrey have emphasized patience. At an investment conference in December, David Zaslav, the chief executive of Discovery, said of advertisers, "They're excited about the mission." Discovery will report its quarterly earnings on Thursday. Lately, Ms. Winfrey has increased her presence on the channel, and there is a belief inside OWN that "Oprah's Next Chapter" is becoming a centerpiece - which explains why she would seek to steer her Twitter followers to it on Sunday night. Since the interview show began in early January, it has drawn almost 900,000 viewers on average, significantly more than most other prime-time shows on the channel. The viewership figures for Sunday's episode, the one that will come with an asterisk, were not available as of Monday evening.