US market study group Nielsen said Tuesday that it has agreed to buy media specialist Arbitron for $1.2 billion in cash. Nielsen said it is offering $48.0 (36.4 euros) per share for Arbitron, a premium of 26 percent compared with the company\'s closing share price on Monday. \"The transaction has been approved by the boards of both companies and is subject to customary closing conditions, including regulatory review,\" the statement said. The purchase is intended to help Nielsen cover media areas such as streaming audio, it added. \"The high level of engagement with radio and TV among rapidly growing multicultural audiences makes this central to Nielsen’s priorities,\" it added. An attractive part of Arbitron\'s activities is its ability to monitor radio audiences, since more than 92 percent of adults and teenagers in the United States are reached by radio, according to Arbitron chief executive William Kerr. \"By combining Nielsen’s global capabilities and scale with Arbitron’s unique radio measurement and listening information, advertisers and media clients will have better insights into consumer behavior and the return on marketing investments,\" he was quoted as saying. The two companies together generated $6.0 billion in sales in the 12-months ending September 30, and had adjusted pro forma core earnings of $1.7 billion, the statement said.