The Use of Images in an Item-Person Map

Abstract

Results that employ Rasch (1960) analysis are often reported in the form of an item-person map, which show the relationship between two key variables: item difficulty estimates and person ability estimates. The map displays results numerically in the form of logits. This paper presents the results of an analysis, using the 'Quest' (Adams & Khoo, 1993) statistical package, for individuals (N = 117) who performed the fundamental skill of the basic forward roll, in gymnastics. Initially the 'Quest' package was employed to confirm the underlying construct, namely, the quality of the individual's performance. However, within the realm of the psychomotor mode of learning, the use of numbers, as they are traditionally employed in reporting statistical results, may not achieve a 'user friendly' status for either physical education teachers or sporting coaches. Because data were recorded using digital images, the results could be reported through the linking of photographs to in the step difficulties previously only presented in numerical format. These images depict what the different aspects of the roll actually 'look like', whilst still maintaining the integrity of the item-person map. As such, the degree of difficulty were visually linked to the quality of student performances for the forward roll. The individuals who took part in this study represent an a sample who are at both ends of the limits of ability to perform a roll. Their ages ranged from 4 years to 42 years, and comprised three cohorts, namely children, young adults and older adults. This approach brings together previously unconnected elements of data, analysis and interpretation of results.