Photography by Dylan Parker

A couple of years ago I was asked during a sales presentation what I thought was the most essential ingredient for a successful project. My answer was "mutual trust". People
in the room were staring at me like I was some kind of Softy Oozy New Age Treehugger. I switched very fast to the normal "plan-and-control" crap to get happy faces again.

Today I would provide the same answer to that question. Trust is essential to doing successful projects, and therefor a core concept for Project Management. But to avoid this "Treehugger" image, let me give you a view on how trust can be modelled, so we put some hands and feet to this rather abstract idea.

As a starting point we take the Prisoners Dilemma (PD) as discussed in this posting. In essence it is a situation where

• 1) if people cooperate both have success,
• 2) if one person is taking advantage of the other (defect) this person has an even larger benefit, but the other suffers a loss,
• 3) if both persons defect they loose both. In a situation like being in prison, you have only those two options, cooperate and defect.

However in more general circumstances, like projects, you can have a third: don't play, walk away, just exit. For this posting I will simplify a project to a series of prisoners dilemma's where the strategies can be cooperate, defect and exit.

Earlier I talked about the idea of "iterative PDs" where an enormous series of PDs are performed behind each other and the choice of strategy is based upon the outcomes of the previous iterations (remember Tit-For-tat? :)). History plays an important role in choosing a strategy. Central question is "Do you trust the other party to cooperate?" "Trust" is defined as "have confidence or faith in" but also as "reliance: certainty based on past experience". Based upon the things that happen in the past, you adapt your strategy.

Having Only One Shot

But what if you haven't done a zillion iterations? What if you meet a person for the first time and you are confronted with a prisoners dilemma? Researchers call this the "one-shot prisoners dilemma". In a situation like this, people are trying to determine the "trustworthiness" of others. They are trying to read "telltale signs", look for behavior or other marks that they identify with trustworthiness. This might be as simple as being friendly and saying "hello" every time you see someone down the hall. Perhaps you have automatically more trust in someone wearing a suit, or a person with PhD behind his name. The idea is that you are trying to detect signs of trustworthiness, whatever
that my be for you.

Next to this detection, the projection of your own intentions plays a role in the decision of the strategy; if you want to cooperate you are more likely to be biased into "seeing" the other as trustworthy. So, we use projection and detection as a mechanism to compensate for the lack of history one has in one-shot Prisoner Dilemma's.

How people detect the tell-tale signs of trustworthiness is not only based upon behavioral markers that society associates with it; it has also to do with the similarity of the other with you. Persons that are more viewed as being equal or "the same" or more likely to be considered honest and sincere towards you. Translated to terms of social networks: people closer in social networks are more likely to consider each other trustworthy than people further apart.

This is not a one dimensional thing, people are associated with multiple social networks and groups. And every social group has its own rituals and signs that communicate its uniqueness towards the world outside the group. If you have a lot of aspects associated with a certain social group, you will more likely be considered trustworthy by members of the same group.

The only question remaining is: do you trust this model?

This posting is largely based upon THE EVOLUTION OF TRUST AND COOPERATION. BETWEEN STRANGERS:. A COMPUTATIONAL MODEL