Posted in Psychology & Medicine

Tit For Tat

In human society, there are many ways for a person to interact with others when in a group setting. Some may choose to be selfish and only be out for their best interests, while others may choose altruism and cooperate with each other. The mathematical model that tries to predict human behaviour and outcome in these settings is the Prisoner’s Dilemma – the core of game theory. Tit for tat is one strategy that can be employed in such a setting.

The basis of tit for tat is equivalent exchange. A tit for tat player always chooses to cooperate unless provoked. As seen in the Prisoner’s Dilemma, if both players cooperate, both benefit (let us say 3 points each); if one player defects, that person gains more than from cooperation (5 points) while the tit for tat player gains 0 points.
If a tit for tat player is provoked, that player will retaliate. However, the player is also quick to forgive. Ergo, if the other player chose to cooperate, the tit for tat player (following the principle of equivalent exchange), will also cooperate. If the other player defected, the tit for tat player loses the first round and then chooses to defect from then on.
Note that tit for tat strategy only works when there is more than one game so that the player has a chance to retaliate.

Let us use an example to illustrate why tit for tat strategy works. In this scenario, two tit for tat players and two defectors all play six games each, using the above point system (if both defect, they each receive 1 point). The results are as follows:
  • Tit for tat vs defector: Tit for tat loses first round, both defect for next 5 rounds (5 vs 10)
  • Tit for tat vs tit for tat: Both cooperate on every round (18 vs 18)
  • Defector vs defector: Both defect on every round (6 vs 6)

When the points are added up, a tit for tat player gains 28 points (5 + 5 + 18) while a defector only gains 26 points (6 + 10 + 10). This is a surprising turn of events, as the defectors never lost a round and tit for tat players never “won” a round. This goes to show how cooperation leads to better long-term results while selfishness prevails.

There are shortcomings of this strategy. If there is a failure in communication and one tit for tat player mistakes the other’s actions as an “attack”, they will retaliate. The other player then retaliates to this and a vicious cycle is formed. This is the basis of many conflicts ranging from schoolyard fights to wars (although interestingly, tit for tat strategy is also found during wars in the form of “live and let live”). One way to prevent this is tit for tat with forgiveness, where one player randomly cooperates to try break the cycle (a defector would respond negatively while a tit for tat player will accept the cooperation), or the tit for two tats, where the tit for tat player waits a turn before retaliating, giving the opponent a chance to “make up for their mistake”.

Computer simulations have all proven that tit for tat strategy (especially the other two types mentioned just before) are extremely effective in games. In fact, it is considered one of the most optimal strategies in overcoming the Prisoner’s Dilemma.

In human societies, there is usually a mix of “nice people” and “selfish people”. By cooperating and trusting each other, we can produce a much greater gain over time compared to being selfish. And since society still unfortunately has “defectors”, you can retaliate to those who refuse to cooperate by defecting on them also. Ergo, a good approach to life is to initially reach out your hand to whoever you meet and treat them from there on according to how they respond. If they take your hand and want to cooperate, treat them with altruism and help them out. If they swat your hand away and try to use you for their selfish gain, it is fine to shun them and not help them out.

Through cooperation, understanding and connection, we can build a far more productive and efficient society, just like the ants.

Posted in Psychology & Medicine

Transactive Memory

It is common to find couples, families or teams where someone always asks another member about a certain memory, while the opposite happens for a different memory. For example, a mother might always consult his son about computers and technical difficulties, while the father might always consult the mother about his plans for the month. This kind of “shared memory” is named transactive memory, where a group becomes organised in a way to share memory around in an efficient manner. This is usually done by the group reorganising itself so that each member specialises in a certain field, with the other members only remembering that that person is the expert. This means that instead of memorising every field, you can simply remember who is the expert in that field. It is much like learning where the reference text is rather than learning the contents.

Although it may look like dependence, transactive memory is an extremely useful tool in tight groups such as a couple or a small team. By having members specialise in certain domains of knowledge, the group is able to expand their capacity to acquire knowledge and create innovation. Transactive memory allows for a group to become efficient and effective in learning and retrieving knowledge. Overall, it improves decision making processes and the efficiency of the group, allowing for better outcomes. This is achieved by the division of responsibilities from specialising, shortening the time needed for finding the appropriate knowledge (as everyone knows the “guy” or “gal” to go to) and the shared understanding of the teammates regarding the interpersonal relations in the team. This means that everyone knows exactly who to go to for a certain domain of knowledge, while understanding their strengths and weaknesses, allowing for well coordinated interactions. Because of this, transactive memory only works in groups with limited numbers, with the maximum number being similar to the Monkeysphere (150).

Many studies prove the effectiveness of transactive memory. It has been found that couples have much better memory recollection compared to when they are paired with a stranger. In the modern technological era, transactive memory has expanded to the internet, with studies showing that people are more likely to know the source of information (such as Wikipedia) rather than the actual information. Given the ease of access to the internet and large databases containing all the information we need, sometimes it is far more efficient learning how to find these sources rather than rote learning all the information.