Measuring preferences and the problems of identifying proximate needs

Current methodologies for measuring choices are the product of early psychological research into behavioural mechanisms, particidarly learning. In applied behaviour studies, much of the emphasis has been on the use of preference tests to assess animals’ motivation, and hence proximate need for, various forms of stimulation. Preference tests are based on a modular view of animal behaviour, where animals are presented with physical compartments each containing different resources such as food or social partners. An obvious limitation of the approach is that simple preference tests may do little justice to the complexity of animals’ behavioural organization and environmental preferences. Variability of choice behaviour also poses a considerable problem, as it may prevent us understanding and interpreting short-term choices and consequently describing the proximate needs of the animal. We also believe that the approach of applying consumer economics to quantify the value of resources to animals is increasingly moving preference testing away from measuring proximate to measuring ultimate need. This shift in emphasis does not appear to have been recognized. The risk is that the approach will only identify basic needs (e.g. related to growth and reproduction) but be insensitive to the proximate behavioural needs that it set out to quantify. In general, the focus of welfare-related preference testing should shift from the measurement and description of preferences to the more strategic task of understanding the rules governing short-term choices. We will be unable to measure proximate need unless we can develop a theoretical framework better able to interpret short-term behavioural choices.