for valuable comments and suggestions. 1 Valuation gaps and exchange asymmetries are often referred to as "endowment effects." The name is confusing when it comes to the cause of gaps and asymmetries because it implies that endowment is the cause. For this reason, some have adopted less theory-suggestive names for the observed phenomena (e.g., Plott and Zeiler 2005, 2007). I use "valuation gap" and "exchange asymmetry" throughout depending on the context in which the phenomenon is observed. I use "reluctance to trade" to refer to the general phenomenon. 2 See also, Biel et al. (2011) ("At present, there is no sign of an approaching consensus. . .") and Lunn and Lunn (2014) ("There remains no agreed explanation for the finding that experimental subjects and survey respondents generally set a minimum selling price for an item that is two or more times higher than the maximum those without the same item will pay to acquire it").