Tom Osborne and Gregor McLennan responded to some aspects of your question in a number of articles that they published a couple of years ago. You may want to check the following: http://www.tandfonline.com/doi/pdf/10.1080/1369823042000241267; http://www.tandfonline.com/doi/abs/10.1080/0308514042000285224; http://www.tandfonline.com/doi/full/10.1080/0308514042000285251?src=recsys