Element salience as a predictor of item difficulty for Raven's Progressive Matrices

Raven's Progressive Matrices is a frequently used intelligence test, and it has been suggested that the major determinant of difficulty for each item is its numbers of elements and rules, and its rule complexity. The current study investigated another potential source of difficulty-element salience-items are harder where their elements are difficult to identify. We investigated two aspects of this: whether item elements are (1) overlapped; and (2) based upon familiar versus unfamiliar shapes. Three sets of newly devised matrices were compared to the original items: (1) easy to identify elements (European letters); (2) difficult to identify elements (Invented 'letters'); and (3) Overlapped elements (using European letters). The original items (with many overlapped and/or unfamiliar elements) were hardest. Performance was significantly better when item elements were either difficult to identify but not overlapped or overlapped but easy to identify. Performance was best when item elements were neither difficult to identify nor overlapped. It is suggested that although element salience can influence the working memory load of an item, the skills necessary for successful element identification are not necessarily related to working memory capacity. (C) 2006 Elsevier Inc. All rights reserved.