From Sangyoon Park:
Through a field experiment at a seafood-processing plant, I examine how working alongside friends affects employee productivity and how this effect is heterogeneous with respect to an employee’s personality. This paper presents two main findings. First, worker productivity declines when a friend is close enough to socialize with. Second, workers who are higher on the conscientiousness scale show smaller productivity declines when working alongside a friend. Estimates suggest that a median worker is willing to pay 4.5 percent of her wage to work next to friends.
That is from American Economic Journal: Applied Economics, via Adam Ozimek.