Researchers from The Ohio State University found that disruptive inventions and innovations tend to come from research conducted in cities, not in the suburbs. Cities encourage natural social interactions between scientists and engineers in all fields.

Previous research has suggested that population density is a major factor in innovation. The team took a closer look at metro areas and found that most patents come from suburbs. Three-fourths of patents came from places with density below 3,650 people per square mile in 2000.

Cities are more likley to produce disruptive innovations.

Disruptive and unconventional inventions, which are more likely to be produced in the cities, combines research from different tech fields. For example, acoustic research and information storage research were combined to create the iPod.

The team found that urban and suburban areas play a prominent role in innovation, but in different ways. Large, innovative companies perform research in large office parks outside of main city centers. Innovative companies are successful when they use meetings or conferences to capitalize on scientists who work together.

They also analyzed over one million U.S. patents between January 2002 to August 2014 using geolocated data from the U.S. Patent and Trademark Office. This data allowed them to see exactly where patents were coming from and helped find what kinds of innovations were produced. New patents were marked as unconventional if the inventors cited work in widely different fields.

Researchers say cities may provide more opportunities for creative people in different fields to interact casually in social settings. This allows for employees in widespread fields to talk which often leads to productive partnerships.

This study proves that there is value in tech parks that gather a variety of start-up companies in one place. But these tech parks would have to be structured in a way that would allow employees of different companies to interact regularly and share ideas.

A paper on this research was published in the Economic Journal.