Several other data specialists, mostly from Google, have left their jobs to wrangle lots of information in new ways. David Friedberg, a former product manager at Google, has started the Climate Corporation, which uses government data on weather, soil porosity and the root structures of wheat and soybeans to write crop insurance.

Mr. Elbaz is also an investor in Kaggle, which awards cash for finding data patterns. It was used by NASA, for example, to find a better way to measure the shape of galaxies; in the first week of competition, a Ph.D. student in glacier mapping had outperformed NASA’s algorithms. He has also put money into ZestCash, which makes payday loans that are cheaper than the industry’s average, judging risk via criteria like cellphone bills and how its applicants read the ZestCash Web site.

The ZestCash C.E.O., Douglas Merrill, once ran Google’s internal information systems.

“We feel like all data is credit data, we just don’t know how to use it yet,” he says. “This is the math we all learned at Google. A page was important for what was on it, but also for how good the grammar was, what the type font was, when it was created or edited. Everything. What Gil is doing at Factual is the same. Data matters. More data is always better.”

MR. ELBAZ was born in Washington, D.C., and grew up in Ohio, Texas and Florida. His father, who was born in Morocco and grew up in Israel, was a school principal and professor of Hebrew literature. His mother, a journalist, died when Mr. Elbaz was 18. At age 3, he began writing a repeating series of numbers at preschool. He read almanacs and enjoyed watching the crawl of stock prices on TV, seeking patterns.

“He would go to a lot of math competitions, and come out with three or four prizes,” says Nissim Elbaz, Mr. Elbaz’s father. “In between the math contests he’d take tests in physics for fun. When I would tell him what a genius he was, he’d give me a dirty look, so I learned to keep it in my heart.”

The elder Mr. Elbaz recalls that when he tried to explain the Israeli-Palestinian conflict to him, the son replied that the hatred would end if the two sides could just agree on the facts.

From an early age, Mr. Elbaz would also figure out math-related businesses — like buying the entire supply of a single brand of baseball cards in El Paso, Tex., then reselling them at three times the money at a memorabilia convention.