In "Status Quo Anxiety" in The New Yorker, James Surowiecki discusses a concept familiar to economists and frustrated garage sale shoppers:
"the so-called 'endowment effect': the mere fact that you own something leads you to overvalue it."
Surowiecki summarizes two experiments demonstrating the endowment effect. In one experiment, students who were given a cup were asked how much they'd be willing to sell it for, and students without the cup were asked how much they'd be willing to pay for it. According to Surowiecki, "the new owners of the mugs demanded more than twice as much as the buyers were willing to pay." In another study, people who won tickets were asked how much they'd be willing to sell them for, and people who didn't win tickets were asked how much they'd be willing to pay for them; "those who had, by pure luck, won the tickets thought the ducats were fourteen times as valuable as those that didn't."
What does this mean for us fantasy football junkies? It means you probably value the players on your roster more than other managers in your league value the players on your roster. It's one reason I avoid making trades before the NFL season starts. After week one, player value starts fluctuating, backups on your bench emerge as valuable commodities, and you discover your team's position needs. But between the end of the draft and the beginning of the season, I usually just sit on my drafted roster.