| Choice | You Get | Friend Gets |
| Choice A: | $40 | $45 |
| Choice B: | $0 | $5 |
This display indicates a choice between two alternatives, Choice A and Choice B. If you select Choice A, then you get $40 and your friend gets $45. If you select Choice B, then you get $0 and your friend gets $5. Which would you prefer? This case should be easy: Both you and your friend would be better off to get Choice A than Choice B.
You are asked to indicate which alternative you prefer and to judge the strength of preference by clicking along the row of buttons to indicate which you prefer. If you prefer Choice A, you should click to the left of the center; if you prefer Choice B, you should click to the right of the center. And if you like both alternatives equally, you should click the button right in the middle of the scale. The greater the difference between the two alternatives, the farther your click should be from the middle. In the case above, this is a big difference between A and B, and you should click far to the left.
Now consider the following case:
| Choice | You Get | Friend Gets |
| Choice A: | $25 | $5 |
| Choice B: | $20 | $80 |
This case is more difficult to judge because if you choose A, you get $25 and your friend gets $5, but if you choose B, you get $20 and your friend gets $80. In this case, you would be better off to choose A, but your friend would be better off if you choose B. In this case, you have to trade off between what you will receive yourself and what you are doing to help your friend. If you would prefer A, you click to the left of center; if you prefer B, you should click to the right. If these are equally attractive, you should click in the middle.
Assume that your friend will receive his or her share as cash in the mail, with a letter saying that it is the prize from a lottery at the Mall. You should assume that your friend will NOT learn of your decisions, and you should assume that your friend will keep what is given to him or her.