“We have more scientists and engineers per square mile than anywhere in the world.”

New Jersey has long held the title of most densely populated state in the country.

But the Garden State has an even more prestigious ranking, according to a recent advertisement placed by Choose: New Jersey in the Wall Street Journal.

The July 30 ad reads in part: “New Jersey has a rich tradition of bringing the world some very big thinking. In fact, we have more scientists and engineers per square mile than anywhere in the world, making ours one of the most highly skilled and educated workforces available.”

That’s quite a claim for any state to make so for this fact check, we are focusing only on the statistic about scientists and engineers. And it seems Choose: New Jersey’s calculations add up.

Let’s look at how Choose: New Jersey, a nonprofit group that markets the state to attract businesses and jobs, came up with their statistic. Choose: New Jersey is part of the Partnership For Action, the Business Action Center and state Economic Development Authority.

Melissa Hensley, chief marketing officer for the group, said the group compared geographic and employment data from four organizations: the Census Bureau’s American Community Survey, the CIA’s World Fact Book 2012, the Organisation for Economic Co-operation and Development and the National Science Board.

“All of it came down to an apples-to-apples comparison to the extent possible between a state and country,” Hensley said.

The Census Bureau’s Population Reference Bureau listed New Jersey as having 260,655 scientists and engineers in 2010. That number divided by New Jersey’s total land area of 8,722.58 square miles equals 29.88 scientists and engineers – the highest number among all states and a list of 37 countries.

“I read somewhere that New Jersey is the most densely populated state in the U.S., so I guess you could extrapolate from that that there are more scientists per square mile than anywhere else,” Brian Bell, a spokesman for the California Institute of Technology said in an e-mail. “Although Massachusetts might give N.J. a run for its money. California has lots of smart people, but we have huge deserts and lots of empty space too.”

Bell’s guess is accurate.

Massachusetts has the second highest number of scientists and engineers, at 23.47 per square mile, followed by Maryland, at 20.97. California is 10th on the list.

A similar calculation was used for other countries by measuring the number of researchers – a more broad term that includes scientists and engineers – per 1,000 of employed people. Breaking that figure down and comparing it against country size, we determined that Israel tops the international list, with 5.10 scientists and engineers per square mile (Choose: New Jersey’s calculations were adjusted to consider countries in square miles instead of kilometers). Rounding out the top three are Japan, at 4.46, and Belgium, at 3.16.

If both lists are put together, New Jersey and 11 other U.S. states lead the world in number of engineers and scientists per square mile before Israel joins the rankings.

“The numbers reflect what we regularly hear from businesses considering locating or expanding in New Jersey – that if a company is looking to benefit from a high concentration of very skilled talent, New Jersey is a prime location,” Hensley said in response to our findings.

Our ruling

Choose: New Jersey said in an advertisement that “we have more scientists and engineers per square mile than anywhere in the world,” making the state’s workforce one of the most skilled and highly educated.

Choose: New Jersey used a variety of data to reach its conclusion, from the U.S. Census Bureau to the CIA World Fact Book and more. PolitiFact New Jersey vetted the calculations and found that the Garden State does top the world in number of scientists and engineers per square mile: 29.8.

We rate this statement True.

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