If the bene ciary of an altruist's gift can be expected to use this gift e ciently, then a pure altruist (one who cares about the bene ciary's utility level, but not how utility is obtained) should only give gifts of money. This is often interpreted to mean that any other type of gift is evidence of paternal altruism. However, it is known (Linbeck and Weibull (1988)) that altruism creates an in...

It is known from a previous paper [3] that Katona’s Intersection Theorem follows from the Complete Intersection Theorem by Ahlswede and Khachatrian via a Comparison Lemma. It also has been proved directly in [3] by the pushing–pulling method of that paper. Here we add a third proof via a new (k,k+1)-shifting technique, whose impact will be exploared elsewhere. The fourth and last of our proofs ...

Do higher wages elicit reciprocity and hence higher productivity? In a field experiment with 266 employees, we find that paying above-market wages, per se, does not have an effect on productivity relative to paying market wages. However, structuring a portion of the wage as a clear and unexpected gift (by offering a raise with no further conditions after the employee has accepted the contract –...

We consider a new type of asymmetric rendezvous search problem in which player II needs to give I ‘gift’ can be the form information or material. The gift either transfered upon meeting, as traditional rendezvous, it dropped off by at location he passes, hope will found I. might water bottle for traveller lost desert; supply cache Captain Scott Antarctic; important (left gift). common aim two p...