The studies presented in this article explore a human-centered conceptualization of agents and agency based on the observation that people attribute agency to sufficiently complex interactive systems. Although agency attribution appears to be an unconscious human response, findings from social psychology, affective computing, and perceptual-motor studies suggest agency attribution influences human–computer interaction (HCI). Three studies are presented that examine whether recent findings on agency attribution in physical environments also apply in the virtual environments characteristic of HCI. Results of the studies indicate that agency effects operate in desktop computing environments. Agency effects, however, appear to be influenced by learning effects that preserve a previously observed relationship between perception and action but alter how this effect is expressed. Results suggest that there are both bottom-up and top-down contributions to agency effects in HCI.

Reports on an empirical investigation of the relationship between print and hypertext reading skills. The subjects in the study were university students at a public Midwestern US university. A repeated-measures, counter-balanced design was employed. Subjects were categorized as high- and low-ability readers based on a standardized measure of reading achievement. The experimental tasks required subjects to answer questions using both print and hypertext versions of an academic advice handbook. A number of significant effects were observed, including a practice effect, a format effect that favored print over hypertext, and a question-set effect. Although this study provides support for the claim that readers find hypertext more difficult, there was no clear evidence that hypertext differentially disadvantages less able print readers.