(Reuters) - Canadian private equity firm Onex Corp (>> ONEX Corporation) said it would buy market research company Nielsen Holdings NV's (>> Nielsen Hldg NV) expositions business for $950 million in cash.

Nielsen Expositions produces more than 65 business-to-business trade shows and conferences in the United States every year.

"Divesting the expositions business allows us to focus on these core areas that provide our clients with a comprehensive understanding of consumers," Nielsen Chief Financial Officer Brian West said in a statement on Monday.

Nielsen Expositions had revenue of about $183 million for the year ended December 31, roughly 3 percent of Nielsen Holdings' total revenue.

Nielsen, best known for its TV ratings business, also provides a host of other data services including the measurement of traffic to websites, competing in that area with ComScore Inc (>> COMSCORE, Inc.). It also provides information about the shopping habits of consumers.

Onex Partners III, Onex's $4.7 billion private equity fund, will make an equity investment of about $350 million in the business, of which Onex Corp's share is about $85 million. Onex has about $15 billion of assets under management.

The deal, which includes a termination fee of $61.75 million, is expected to close in the second quarter.

Reuters reported in March that Nielsen Holdings was in the early stages of selling its expositions business and had hired Credit Suisse to help with the sale.

Nielsen was bought by a group of private equity firms including Blackstone Group (>> The Blackstone Group L.P.), Carlyle Group (>> Carlyle Group LP) and KKR & Co (>> KKR & Co. L.P.) in 2006. The company went public in 2011.

The deal with Onex comes about five months after Nielsen said it would buy radio ratings company Arbitron Inc (>> Arbitron Inc.) for $1.26 billion in a deal that would create a powerhouse, placing the measurement of audience for TV and radio under one company.

Nielsen said at the time that it had a financing commitment for the total transaction amount.

"We will be able to do the Arbitron deal with a lot less debt. So we will need to raise $950 million less debt for that transaction," West said on a conference call with analysts.

Fried Frank acted as legal adviser to Onex.

Nielsen shares rose 1 percent to $36.03 on the New York Stock Exchange on Monday. Onex shares rose 1 percent to C$49.99 on the Toronto Stock Exchange on Monday.

(Reporting by Bhaswati Mukhopadhyay in Bangalore; Editing by Sreejiraj Eluvangal, Supriya Kurane)