When it comes to technology and science assets, Pennsylvania is doing better than four years ago, enough to boost a national ranking from 16th to 13th.

The rankings come from the Milken Institute, a California-based think tank, which last week gave each state a technology and science index in a report on the "intangible economy."

"Pennsylvania is doing well. It certainly didn't drop," said Kevin Klowden, managing economist for the Milken Institute.

"But at the same time, the key is how much growth will the companies have over the next couple of years. ... That's what's going to make a difference next time."

The report placed Massachusetts at the top with 82.61 points and Mississippi at the bottom with 29.81.

Pennsylvania ranked 13th with 63.23 points; Ohio 36th with 45.25 points and West Virginia 49th with 30.49 points.

The rankings were calculated on a per capita basis, so it was not an advantage to be a large state.

"If you go by absolutes, Pennsylvania is a strong state. The issue is that neither Pittsburgh nor Philadelphia is quite strong enough on their own to lift the state into the top 10," Mr. Klowden said.

He said both major cities have strengths -- Pittsburgh in hard sciences such as computers and robotics and Philadelphia in life science fields -- but "they're not quite as strong as the strongest centers in the country."

Pennsylvania showed sizable improvements in two areas: education and venture capital.

The report called Pennsylvania a "strong mover" in human capital investment, "advancing 10 positions due to its strength in recent graduates in all levels of science and engineering."

Pennsylvania, for example, ranked fifth in the number of doctorates in science and engineering per 1,000 civilian workers in 2005.

State Education Secretary Gerald Zahorchak said he thinks the rankings reflect the investment the state has been making in beefing up science education at all levels.

In the category called risk capital and entrepreneurial infrastructure, Pennsylvania moved up 14 rungs.

Mr. Klowden said that both public and private investments have helped Pennsylvania, including the Ben Franklin Technology Partners, which has four regional centers aimed at helping technology-driven enterprises.

He said many of the investments were distributed throughout the state to small and mid-sized companies.

In part because the investments were so widespread, Pennsylvania dropped 13 places in technological concentration and dynamism.

Mr. Klowden said that a concentration can be a magnet for employers and employees.

"If the companies continue to grow, the concentration will begin to build back up again," Mr. Klowden said.

Kevin Lane, public relations director of the Pittsburgh Technology Council, said, "Pittsburgh, for my money, has one of the most concentrated technology industry clusters of any city its size in the country."

He said the region in 2005 had nearly 7,300 companies in technology, including health services, about 10.8 percent of all companies in the region. He said they accounted for about a quarter of the region's payroll.

"That to me is a significant statement for the state of technology in the region and one that bodes well for future concentration," Mr. Lane said.