Instructions (treatment PARTIAL)
Welcome to our experiment!
Please read these instructions carefully! Do not speak to your neighbours and keep quiet
during the entire experiment! In case you have a question raise your hand! We will then come
to you.
In this experiment you will repeatedly make decisions. Doing this you can earn money. How
much you earn depends on your decisions and on the decisions of other participants. All
participants receive the same instructions.
All participants stay anonymous to the experimenter and also to other participants.
In the experimental situation there are two agents called A and B, respectively. In each round
every A will be randomly matched with a B. Altogether there are eight participants. All
participants are randomly assigned a role (A or B) at the beginning of the experiment and
roles will be kept throughout the experiment. There will be four A-participants (A1, A2, A3,
and A4) and four B-participants (B1, B2, B3, and B4).
At the beginning of each round each A-participant is randomly matched with a B-participant
by the computer. That is, in each period the computer randomly chooses one of the A-
participants and one of the B-participants who interact with each other in this period. This
process is repeated in the next period. Therefore, you may meet with the same participant in
two consecutive periods (in one out of four cases) or meet a different participant in the next
period (in three out of four cases). In any case A-participants are told with whom they have
been matched, i.e., A-participants will learn whether they have been matched with B1, B2, B3,
or B4. (Of course, they will never learn which person in the room is behind any of these
labels.) B-participants will NOT learn with whom they have been matched.
Once participants have been matched, it is A’s turn to make a decision. More specifically, A
has to choose between option X and option Y. If he picks option X, A will earn 20 p and B will
earn 15 p. If he picks option Y, the payoffs depend on B’s choice who has to decide whether
he wants to go „left“ or „right“. If he decides to pick „left“, A will earn 5 p and B will earn
50 p. If he decides to pick „right“, A will earn 30 p and B will earn 25 p.
These rules are illustrated in the following „tree“:
