A dialogue

Gambler to decision analyst: I would sure like to have a copy of that new book “Speculator's Almanack” by Lit L. Nohn. It received such a favourable review in Portugaliae Oeconomicae.

Decision analyst: You are a lucky man – I incidentally happen to have a few copies with me. In fact, I think I will offer you the following gamble: you have the option of either having one copy for sure or an even chance of getting either no copy or two copies. Which option do you choose?

G: What a silly question! Of course I choose the one copy for sure!

DA: I see. What about if I change the second option to an even chance of getting zero or three copies?

G: Same answer, of course. I can't understand why you ask! I have no more use for a third copy than for a second one.

DA: So you are pretty risk averse then. The expected value of the last option is 1½ copies, as you know, but yet you choose something with an expected value of only one copy. This must be accounted to your aversion to taking risks.

G: Come on, don't be silly! You know me, you know that I am a gambler and that I have a temperament for taking risks. But that has nothing to do with this gamble. It is simply that a second or a third copy of a book is practically useless.