Mr. Rascher, the sports economist, says variable pricing is here to stay.

Andrew Zimbalist, a sports economist and professor at Smith College, said such clauses were common in stadium lease arrangements around the country.

The first thing to do is toss out that $25 million loss, says Rodney Fort, a sports economist at the University of Michigan.

Even some sports economists who have been critical of stadium and arena projects elsewhere are intrigued by Mr. Ratner's plans.

In the past, about 12.5 percent of ticket revenues went to the participating teams, along with profits from concessions, billboard ads and parking fees, sports economists said.

A newly revised analysis by Mr. Zimbalist, the sports economist, estimated the net fiscal impact of the entire project at $1.06 billion over 30 years.

"The media companies do tend to be more conciliatory and closer to the players' point of view," Zimbalist, the sports economist, said.

College football and basketball players, those "unpaid professionals," as a leading sports economist, Andrew Zimbalist, dubs them, were physically absent.

Andrew Zimbalist, a sports economist at Smith College in Northampton, Mass., said he doubted the teams would leave the region.

Many sports economists are skeptical of whether stadiums ever serve as engines of economic development, but they are particularly dubious of arenas located in suburbs.