divideandchoose

The divide and choose method is a fair division protocol used to allocate a divisible good, such as land or cake, between two people. It is a simple and effective procedure that ensures both participants feel they have received a fair share. The protocol involves one person, the "divider," splitting the good into two parts that they believe are of equal value. The second person, the "chooser," then selects the piece they prefer.

The fairness of this method lies in the incentives of both parties. The divider is motivated to make the split as equitable as possible because they know the chooser will select the piece that appears more valuable to them. If the divider makes an unequal split, they risk receiving the smaller or less desirable portion. The chooser, on the other hand, is guaranteed to receive a portion they perceive as at least half of the good, as they have the final say in which piece they take.

This method is applicable to a wide range of divisible goods and situations. For instance, it can be used by siblings to divide a cake, by business partners to split assets, or even by countries to divide territory. The core principle remains the same: one divides, the other chooses, leading to a mutually agreeable outcome. The success of the divide and choose method hinges on the assumption that both parties can accurately assess the value of the different parts of the good.