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Kwabena Donkor, Faculty Fellow

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This story is part of the Why Econ? series. Our affiliated students and faculty share why econ matters to them, their work, and our world.

Kwabena Donkor leans on taxi cab

For Kwabena Donkor, driving a New York City taxi while studying economics in college was grueling. He’d wake up before 3 a.m. on Sundays to stand in line to lease a cab, then work a 24-hour shift straight. It was the only way to make ends meet and stay on top of his studies.


The sleepless grind served another purpose — one that ultimately brought him to Stanford, first as a postdoctoral fellow at the Stanford Institute for Economic Policy Research (SIEPR) and then as an assistant professor of marketing in the Graduate School of Business.

Ever curious about people and their experiences, he would conduct mini experiments from behind the wheel. For example, if he drove as fast and aggressively as other cabbies, did he save time? No. Or, would banter with friendlier passengers lead to higher tips? Not necessarily.

“People who were rude would still leave a good tip,” Donkor says.

Donkor, who immigrated from Ghana in 2007 and earned his bachelor’s and master’s degrees in economics from Hunter College, once had dreams of working on Wall Street. But four years as a taxicab driver — with all the fascinating inconsistencies he witnessed across drivers and passengers — sparked an interest in the economics of human behavior.

He took a few detours along the way. He dabbled in labor economics as a research assistant at Princeton, then earned his second master’s and a PhD in the agricultural and resources economics program at the University of California, Berkeley, where his path pointed to a future studying developing countries.

But Donkor never veered far from the world of taxis. While at Princeton, he had uncovered a billion payment records for cab rides in New York City. That data became the basis for his doctoral thesis and, more recently, a detailed analysis of the psychology and economics behind tipping. Among other takeaways, he shows how social norms and on-screen menus of tipping suggestions affect tipping behaviors and how people will tip more when it’s raining or snowing.

Donkor was always drawn to economics because it offers measurable insights into the human experience, and today, his research continues to explore the interplay of social norms and economic behavior. He hopes, for example, to shed light on individual identity and the price at which people will forsake it for personal gain.

Reflecting on his own somewhat unconventional path, he says to future economists: “There are so many ways to get to the same location, and the fastest one may not be the best. Be willing to take a different route.”

Photos by Ryan Zhang

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