Wühr et al. Cogn. Research (2020) 5:50 https://doi.org/10.1186/s41235-020-00253-2 Cognitive Research: Principles and Implications ORIGINAL ARTICLE Open Access The impact of team preferences on soccer ofside judgments in laypersons: a quasi-experimental study Peter Wühr1* , Frowin Fasold2 and Daniel Memmert2 Abstract The present study uses a quasi-experimental design to investigate the impact of team preferences on the accuracy of ofside judgments. In Experiments 1 and 2, supporters of two German soccer clubs (i.e., Borussia Dortmund and FC Schalke 04) judged ofsides in artifcial scenes from a match between the clubs. We expected that supporters of both clubs would less frequently report the ofside position of a forward from the preferred team. The results of Experi- ment 1 partly confrmed the predictions. Both groups reported the ofside position of a yellow forward less frequently than that of a blue forward, and this efect was much larger for supporters of Borussia Dortmund than for supporters of Schalke 04. The diference between groups could be attributed to team preferences. The weaker efect of team preference in supporters of Schalke 04 was attributed to an unexpected perceptual efect that increased the accuracy of ofside judgments for blue forwards in both groups. Experiments 2 and 3 showed the presumed efect of team preferences and the perceptual efect, respectively, in isolation. In summary, the results of our experiments provide evidence for (a) an efect of team preferences and (b) an efect of shirt–background contrast on ofside judgments in soccer. Keywords: Football, Ofside rule, Soccer, Team preference, Wishful seeing Signifcance statement of two German soccer clubs (Borussia Dortmund and A central component of the popular game soccer is the Schalke 04) judged ofside scenes from a virtual match “ofside” rule because it increases the difculty of scor- between the two clubs. Most interestingly, we obtained ing goals and, thus, makes the game more interest- evidence for an impact of team preferences on ofside ing. According to that rule, a player P can only score a judgments, which refected diferent response biases for goal if—at the moment the ball is played to P—at least forwards of the preferred versus the nonpreferred team. two opposing players are between P and the opponents’ Moreover, and unanticipated, we observed an additional goal. Judging ofside is a difcult task, with ofside deci- efect of shirt color on ofside judgments, which most sions often being heavily disputed among the observers likely refected diferences in shirt–background contrasts. of a match. Everyday observation suggests that observ- To conclude, whereas previous studies mostly focused ers often tend to “see” ofside situations in favor of their on perceptual sources of errors in ofside judgments, our team. Our research investigated whether such “wishful study provides evidence for an impact of team preference seeing” can afect—or distort—the ofside judgments on ofside judgments. Future research could investigate of layperson observers. In two experiments, supporters whether similar (top-down) efects might occur in people with experience in soccer refereeing. *Correspondence: [email protected] 1 Department of Psychology, TU Dortmund University, Emil-Figge-Str. 50, 44227 Dortmund, Germany Full list of author information is available at the end of the article © The Author(s) 2020. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creat iveco mmons .org/licen ses/by/4.0/. Wühr et al. Cogn. Research (2020) 5:50 Page 2 of 24 Introduction preferred team. Tat is, supporters of Borussia Dort- Te ofside rule is fundamental in modern soccer. mund might report the ofside position of a player from According to the ofside rule, a player P of the attacking Borussia Dortmund less often than of a player from team can only score a regular goal if—at the moment Schalke 04, and supporters of Schalke 04 might show a teammate passes the ball to player P—player P is not the opposite pattern. Moreover, we sought to deter- closer to the opponents’ goal than the second-last mine if such diferences in reporting ofside positions of defender, including the goalkeeper (cf. FIFA 2015, Laws the preferred team compared to a non-preferred team of the Game, p. 36). Te primary purpose of this rule is might refect a case of “wishful seeing” (cf. Bruner 1957; to make scoring goals more difcult for the players and, Dunning and Balcetis 2013) or, instead, a case of biased thus, more interesting for the observer. However, eve- reporting. ryone familiar with soccer knows that judging ofsides correctly is a difcult task. When a group of people is watching a soccer match, contradictory judgments are Psychological analysis of ofside judgments sometimes made of the same ofside situation. Whereas Judging ofside in a soccer match is the task of a referee some people saw a player in an ofside position, oth- supported by two assistant referees, one on each side of ers did not. Most interestingly, as many soccer fans may the feld of play. Each assistant referee (AR) is respon- have already observed, diferent judgments of the same sible for one half of the feld of play; that is, if team A ofside situations are often correlated with diferent team plays from left to right against team B, then AR 1 will be preferences. Tat is, supporters of the team that scored a judging ofside when team A attacks the goal of team B, goal often judge the position of the scoring player as not whereas AR 2 will be judging ofside when team B attacks ofside, whereas supporters of the opposing team judge the goal of team A. Te AR signals a presumed ofside the position of the same player as ofside. How can this position by lifting a fag; the fnal decision, however, happen? Is it possible that supporters of opposing teams remains with the chief referee. sometimes perceive the same game situation diferently? From a psychological point of view, judging ofside is a Or do supporters simply tend to claim what benefts their perceptual classifcation task where an infnite set of situ- team, independently of the facts? ations must be sorted into one of two categories: ofside In a now classic article, Hastorf and Cantril (1954) were or not ofside. In such a classifcation task, the observer the frst to note striking diferences between how mem- can make two types of correct judgements and two types bers of Princeton University and Dartmouth College of errors (e.g., Macmillan and Creelman 2005). Te cor- described a match between the football teams from both rect judgments involve the classifcation of an actual universities in 1951. Te game was a rough one, with ofside situation as “ofside” (called a “hit”) and the clas- injuries and penalties on both sides, although Dartmouth sifcation of an actual not-ofside situation as “not of- was penalized more often than Princeton. Interest- side” (called a “correct rejection”). Te wrong judgments ingly, when asked a week later, most Princeton students involve the classifcation of an actual ofside position as blamed Dartmouth for starting the “rough” play. In con- “not ofside” (called a “miss” or “non-fag error”) and the trast, most Dartmouth students blamed both teams for classifcation of an actual not-ofside situation as “ofside” starting the rough play. Similarly, after having watched (called “false alarm” or “fag error”). a movie of the game, Princeton students reported twice According to signal detection theory (e.g., Green and as many infractions from the Dartmouth team than from Swets 1966; MacMillan and Creelman 2005), two major their own team, whereas Dartmouth students reported determinants of classifcation performance under uncer- slightly more ofences from the Princeton team. Hence, tainty are sensitivity and response bias. With ofside judg- the results of this report suggest that team preference ments, sensitivity refers to the ability of the observer to may afect perceiving and/or recalling a sports event. In (perceptually) discriminate ofside from non-ofside situ- a later section, we will describe some follow-up research ations. In contrast, the term “response bias” describes the on the classic Hastorf and Cantril study. preference for one or the other response, independently Te present study investigates the impact of team from sensitivity. For example, a supporter of Borus- preferences on ofside judgments in soccer. Terefore, sia Dortmund might prefer the “non-ofside” response we compared the ofside judgments of two groups of over the “ofside” response when a forward of Borussia participants, each supporting a famous German soccer Dortmund is involved in a perceptually unclear ofside team (i.e., Borussia Dortmund vs. F.C. Schalke 04), in situation. Signal detection theory provides formulas for displays depicting scenes from a match between these computing the sensitivity index (d′) and the response- two clubs. Our general hypothesis was that strong team bias measure c from the results of a two-choice classifca- preferences might bias ofside judgments in favor of the tion task (e.g., MacMillan and Creelman 2005).