Fig. 1

a Without mutual exchange. Shows how each person is selected in an iteration exactly once to act as a source. A person may act as target multiple times as shown by the person 6 (P ₆). Every node (person) has an in-degree of 1 and out-degree of 0 or more. Therefore, this type of configuration does not involve the mutual exchange of information. When information of P ₁ is sent to P ₆, P ₁ has already received new information from P ₅ and updated his views. If P ₆ receives the initial information of P ₁, then the interaction is concurrent, otherwise he receives the updated information of P ₁ and interaction becomes sequential. b With mutual exchange: In this case, each person is selected in an iteration exactly once who acts as both source and target. Every node (person) has an in-degree and out-degree of 1 thereby involving the mutual exchange of information. This type of interaction has no contingency on being concurrent or sequential. If there are odd number of people in the experiment, then the last person receives his own information