The endowment effect is the tendency for people who own a good to value it more than people who do not. It is often evoked to admonish investors who seem to over-value what they own, thus foregoing investment opportunities with higher expected future returns. Richard Thaler, who coined the term “endowment effect” in his seminal 1980 paper, explained that “goods that are included in the individual’s endowment will be more highly valued than those not held in the endowment” and that “removing a good from an endowment creates a loss while adding the same good… generates a gain...