It has application to any area of human activity where a decision is made and while it is based on individual ethnographic interviews the decisions of people are examined and interpreted to develop a decision tree model for the group. The method uses ethnographic interviewing to elicit from the decision makers themselves their decision criteria. Ethnographic interviewing involves approaching farmers in a way that acknowledges their expertise in managing a farm and paying attention to what they believe and what they do on their farm, accepting uncritically their views on the relevant issues.
Interviews explore farmers' thinking and records in their own terms their reasons for actions.
Ethnographic decision tree modelling seeks to develop a complete decision tree comprising a series of connecting decision criteria. The decision criteria are discrete questions the answers to which are either true or false for any particular subject. The tree must allow each subject to move downwards through a series of criteria to an outcome which is true for that subject. In addition the tree must combine criteria for all subjects in a logical way. The tree thus tells why a particular outcome is achieved because the outcome is preceded by a set of criteria relevant to particular subjects.