The endowment effect is old news: the amount that we value an object increases once we take ownership of it. The ‘extended version’ shows that the impact of the endowment effect increases with time: our valuation of an object increases more and more as the amount of time that we own it also increases. This is known as the length-of-ownership effect.

A recent study published in the journal Judgement and Decision Making1 has taken an even deeper look at this effect: studying how touching an object increases both our attachment to that object and how much we value it… even if we don’t own it (also in pdf). Here are the key findings of this ‘pre-ownership exposure study’:

  • Touching an object will increase our attachment to it and valuation of it, whether we own it or not.
  • The longer we touch or handle an un-owned object, the greater we will value it and feel attached to it.
  • Simply thinking about an un-owned object increases our valuation of it and how much we feel attached to it.

Related findings, cited in this article:

  • If an object is being sold at auction, the amount that we value the object will increase as the length of the auction increases.
  • Owning a coupon for an object increases our emotional attachment to that object.
  • Making an item the “focus of a comparison” increases its attractiveness and the probability that it would later be selected. We will also feel more attached to the item and will value it higher.

via @stevesilberman and Lifehacker (suggesting that this duration-of-exposure effect’ is an explanation for why we have cluttered homes.)

1 What, you’re not reading Judgement and Decision Making? You should; it’s bimonthly and open access.