Differential item functioning (DIF) occurs when items on a test or questionnaire have different measurement properties for one group of people versus another, irrespective of group-mean differences on the construct. Methods for testing DIF require matching members of different groups on an estimate of the construct. Preferably, the estimate is…

Planning techniques provide a means of systematically evaluating and documenting the impact of alternative land use strategies, thereby enabling state recreational planners to develop policies and programs offensively, rather than as defensive reactions to deteriorating situations. (MB)