Wicker is recognized for significant contributions to ecological psychology and for a widely cited paper on the attitude-behavior relationship.
[2] In subsequent publications, Wicker sought to refine and elaborate the basic environmental unit of ecological psychology, the behavior setting.
According to Scott, "Wicker emerged as the individual in this group of researchers [ecological psychologists following Barker] who has taken the theoretical conceptualizations the farthest.
[3] In 1969, Wicker published a review paper on the relationship between verbal expressions of attitudes and overt behaviors that stimulated much debate and research in social psychology.
Wicker has held Fulbright appointments in Zimbabwe (1989), Ghana (1993), Malaysia (1997), and Japan (2009).