The city’s big companies, in collaboration with Cincinnati and Hamilton County, also developed plans and investment funds for park reconstruction, business investments and new office and residential construction, all aimed at coaxing residents to live downtown and to establish more high-paying jobs.

In 2005, Fountain Square, Cincinnati’s deteriorated cultural and economic center, was rebuilt, prompting new office and retail development nearby. By then, Dunnhumby, housed in a downtown office not far from the square, had grown from four employees in 2003 to almost 100 employees. Some of the young workers moved into the first new apartments developed by 3CDC in the Over-the-Rhine district, the late-19th-century neighborhood where the riot started.

Dunnhumby achieved its rapid growth by inventing the algorithms and big data analytics to help Kroger understand consumer buying habits. The firm’s analysts, for example, found that men and women in two-income households with children typically spent about 16 minutes in a Kroger store. That piece of data prompted new designs in product displays — like one-stop sections for preparing school lunches — in stores that served upper-income single-family neighborhoods.

Dunnhumby’s clients include so many other big retailers and product companies, like Macy’s, which is also based in Cincinnati, that it now employs 750 analysts, programmers, software developers and marketing specialists, nearly 600 of them working in the city.

The company’s new office building, large enough to house 1,100 employees, joins a host of other new or renovated buildings near Fountain Square, including the $56 million, 156-room, 21c Museum Hotel that opened in 2012 two blocks away.

“We see applications for our work across so many industries. Big data really has no barriers,” said Stuart Aitken, DunnhumbyUSA’s chief executive. “We have 35 or 40 job openings right now we’re trying to fill. We couldn’t be in a better place than this city.”