Brian Wansink, professor of marketing at Cornell, and leader of the research team, used The Spice Box restaurant in Urbana, Ill., as a test ground in which a dinner special including wine was offered on Thursdays.
Through hidden cameras, diners were observed and timed and each filled out a survey at the end of the meal, ABC News reported.
Half of the customers got wine labeled as being from California, while the other half got bottles saying it was made in North Dakota.
The California drinkers stayed at the table longer, ate more of the food and ranked the food and wine highest, the study found.
The reality was, everyone was drinking the same wine, a brand available for $2 a bottle, Wansink said.
"If we think something is going to taste good, we look for the qualities that can confirm that expectation," he said. "If we think it's going to taste terrible, we look for things that will confirm that it's bad."