NEW YORK - The media-ratings company Arbitron has settled lawsuits with state officials in New York and New Jersey over its new system for measuring radio audiences, which critics accused of undercounting minority listeners.

The deal, announced yesterday, requires Arbitron to make changes in how it recruits survey participants in the Philadelphia and New York radio markets to ensure that its samples contain an accurate proportion of blacks and Hispanics.

The New York market covers much of North and Central Jersey. The Philadelphia market encompasses significant portions of South and Central Jersey.

Arbitron also agreed to pay $100,000 to the National Association of Black Owned Broadcasters and the Spanish Radio Association, and to buy $25,000 in ads to support minority radio. The company will pay an additional $260,000 to New York and $130,000 to New Jersey.

Arbitron has maintained that its system did not undercount minorities. It said most of the changes included in the settlement were planned before the legal action.

The dispute involved the company's newly deployed Portable People Meters, electronic devices about the size of a cell phone that have transformed the way the company calculates ratings.

The devices, meant to be worn on a belt, are given to volunteers for up to two years to record the stations they hear as they go about their day. The meters detect inaudible data codes, sent out with each radio signal, and log the results automatically.

Arbitron has touted the system as a vast improvement over its old surveys, in which participants recorded their listening habits in diaries.

The system went online in Philadelphia and Houston in 2007, then had a broad rollout in October. It is now used in 14 markets, including New York, Chicago, Los Angeles and Dallas.

Criticism poured in after stations catering to black and Hispanic listeners saw their ratings drop sharply as the system was phased in.

Some analysts said it was possible that participants in the old system had exaggerated how often they listened to their favorite stations, especially ones with which they shared a cultural identity.

Arbitron said that ratings for talk radio also had declined, and that the devices revealed that people listened to more radio than previously thought, but for shorter periods of time.

Other critics, including the owners of several stations geared toward minorities, accused the firm of failing to recruit enough black and Spanish-speaking participants.

New York Attorney General Andrew M. Cuomo brought a lawsuit against Arbitron in October in which he asked a judge in Manhattan to block further use of the system in the New York area. New Jersey's attorney general filed a similar suit.

A key part of the settlement requires Arbitron to increase the number of people participating in the survey who do not have a landline phone. Currently, most volunteers need a home phone, which probably led to an underrepresentation of people who own only cell phones.