Several factors thought to influence the representativeness of behavioral assessment data were examined in an analogue study employing a multifactorial design. Systematic and unsystematic methods of observing group behavior were investigated using 18 male and 18 female observers. Additionally, valence properties of the observed behaviors were inspected. Subjects' assessments of a videotape were compared to a criterion code which defined the population of behaviors. Results indicated that systematic observation procedures were more accurate than unsystematic procedures, though this factor interacted with gender of observer and valence of behavior. Additionally, males tended to sample more representatively than females. A third finding indicated that the negatively valenced behavior was overestimated, while the neutral and positively valenced behaviors were accurately assessed. (Author)