Arrow's impossibility theorem and why investment committees don't work

 

For some odd reason, I was having a discussion with a friend on Kenneth Arrow and social choice theory. It came up when discussing the jungle primaries out in California. Arrow developed what has been called the impossibility theorem which states that if voters have three or more options or alternatives there cannot be a system that keep everyone happy based a criterion of fairness. I will not go into all the details; however, we should think about Arrow when we discuss how investment decisions are made within a committee.

There may be a set of views from each committee member. At the committee meeting, they will be asked to state or rank their views, yet it will be impossible to have these views fairly reflected in the committee decisions. There will be unhappy members and any voting scheme will not reflect fairly the member preferences. You cannot just have a committee vote and assume you will come out with the best answer. You will have an answer, but not one that will satisfy everyone, so the committee may go around and around until some decision is made. 

Perhaps it is better to use a model as a dictator or as the decider of what should be done? Everyone can provide and support the model, but the model will make the preference choices.  One voter and one source of action.