The weights of the general distance

[andreastausend]

The weights used for the aggregation of the marginal distances are a central object of the general distance and decisive for its perfomance. There are several ways of kalibrating them.

Ther first is to use medical expertise to asses, which kind of differences are more or less relevant to compare patients' constitutions.

The second is a sanity test based of the "established illnesses". One such test could be to alternatingly perform a k-means cluster analysis - based on the general distance - and to adapt the weights such that the "established illnesses" are reproduced "well enough" as cluster centers. k would be equal to the number of "established illnesses" or slightly larger.

The third is to regularly adapt the weight such that the general distance between users that declare each other usefull (via a tag and/or via fruitfull interaction) becomes smaller, while the one between "uninteresting" but highly ranked proposed users increases. This could be done weight by wheigt. A weight wab is decreased if the marginal distance between cooperating users user1 and user2 is larger than between say user1 and user3, while user3 is higher ranked in user1's list of proposed users. In the same spirit a weight wab is increased if the marginal distance between cooperating users user1 and user2 is smaller than between user1 and user3. It might be an improvement to monitor this adaptive kalibration by medical experts to improve the quality of such changes.

What needs to be done:

1. Find a meanigfull set of initial values for the weights
2. Implement and cary out one or many of the above kalibrations (using bootstraped versions of the established illnesses)