Response requirements affect offside judgments in football (soccer).

Judging offside in football represents a typical go-nogo task (offside-raising the flag, no offside-no response). Nevertheless, several studies involved two-choice tasks (e.g. offside-press key A, no offside-press key B) to investigate potential sources of errors in offside situations. While go-nogo and choice-response tasks are commonly used in experimental psychology, response preferences may differ between the two tasks. Therefore, we investigated the impact of response requirements on offside judgments in a sample of male participants without experience in professional refereeing. Each participant judged displays of potential offside situations in a go-nogo condition and in a two-choice condition. The results show that response requirements affected the response bias of the participants and suggest that go-nogo requirements increase the preference for the positive response (i.e. the offside response) as compared to the two-choice task. We discuss both methodological and theoretical implications of this finding.