AGGRESSIVE BEHAVIOR

Volume 35, pages 244–258 (2009)

Group Membership, Group Norms, Empathy, and YoungChildren’s Intentions to AggressDrew Nesdale�, Ella Milliner, Amanda Duffy, and Judith A. Griffiths

School of Psychology, Griffith University, Gold Coast, Queensland, Australia

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This study assessed the effect of ingroup norms and empathy on 6 and 9-year-old children’s (N5 161) attitudes and aggressiveintentions toward outgroup members. Prior to an intergroup drawing competition against an outgroup, participants’ empathy wasmeasured, and they were randomly assigned to a simulated group with a norm of direct or indirect aggression, or no aggressionnorm. Results indicated participants’ attitudes were less positive toward the outgroup vs. the ingroup, and that both direct andindirect aggressive intentions were displayed toward the outgroup. Most importantly, the ingroup was liked less when it had anaggression norm, and the participants’ aggressive intentions were not enhanced by the group aggression norm. Empathy was asignificant negative predictor of direct but not indirect aggression intentions. Implications for understanding the instigation andinhibition of children’s aggression intentions are discussed. Aggr. Behav. 35:244–258, 2009. r 2009 Wiley-Liss, Inc.

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Keywords: group membership; group norms; empathy; aggression intentions

INTRODUCTION

Research has revealed that acts of aggression bychildren and adolescents are both pervasive andharmful [e.g., Cairns et al., 1989; Crick, 1996;Kochenderfer-Ladd and Wardrop, 2001; Pellegriniand Bartini, 2001]. Much of this research hasfocused on direct, overt, or physical aggression(i.e., hitting, pushing, taking things, verbal abuse).However, other research has also considered indirectaggression, much of it focusing on relationships asthe mechanism for the delivery of harm [Zimmer-Gembeck et al., 2005]. This type of aggressionincludes aversive acts such as exclusion, manipula-tion, gossip, and deception.Of particular interest to the present research was

the issue of whether young children’s direct and/orindirect aggression would be influenced by theirinvolvement in social groups. This issue has receivedcomparatively little research attention, although thepotential influence of groups on children’s aggres-sion has been noted by a number of researchers [e.g.,DeRosier et al., 1994; Fraczek, 1996; Kiesner et al.,2002; Salmivalli et al., 1998]. The lack of research issurprising given the increasing recognition thatinclusion and belonging are critically important topeople, even young children [Baumeister and Leary,1995; Nesdale, 2007]. Indeed, it has been argued that

individuals probably have an inborn fundamentalneed to belong, which motivates them to establishfriendships and to become members of social groups[Baumeister and Leary, 1995].

Children and Social Groups

Recent research has shown that, certainly byschool age, children seek to be members of socialgroups, that they reveal a tendency to like, and tosee themselves as similar to, ingroup compared withoutgroup members [Bigler, 1995; Bigler et al., 1997;Nesdale and Flesser, 2001; Nesdale et al., 2004,2005a], and that their acceptance by a social groupcontributes to their sense of self-worth [Verkuyten,2001, 2007]. In addition, children have a strong biastoward their ingroup when they are required tomake choices, indicate preferences, or allocaterewards between the ingroup and an outgroup,and they display ingroup positivity vs. outgroup

Published online 23 March 2009 in Wiley InterScience (www.inter-

science.wiley.com). DOI: 10.1002/ab.20303

Received 15 August 2008; Revised 16 February 2009; Accepted 17

February 2009

�Correspondence to: Drew Nesdale, School of Psychology, Griffith

University, Gold Coast, Qld. 4222, Australia.

E-mail: d.nesdale@griffith.edu.au

r 2009 Wiley-Liss, Inc.

negativity in their trait attributions [see Aboud,1988; Nesdale, 2001, for reviews].However, although there is evidence that social

groups can exert a significant influence on children’sattitudes and behaviors, few attempts have beenmade to examine the extent to which groupprocesses influence children’s aggression. Thus, noresearch has assessed the extent to which groupmembers’ aggression is influenced by whetherthe individuals identify with the group, whetherthe group has a norm (i.e., expectations concerningthe attitudes, beliefs, and behaviors to be displayedby group members) of aggression, whether themembers have different positions within the group(e.g., central or prototypical members vs. moreperipheral members), or whether the group issubjected to intergroup competition or confronta-tion. In addition, no research has examined whetherthe effect of these group processes on groupmembers’ aggression is related to individual differ-ence variables such as empathy, social dominance,or authoritarianism.One issue addressed in the present research

concerned the extent to which the aggression ofgroup members is likely to be influenced by theirmembership in a group, in the context of anintergroup competition or confrontation. Accordingto social identity development theory [SIDT,Nesdale, 2004, 2007], in this situation, individualswho identify with a particular group are likely toengage in behaviors that enhance, maintain, ordefend the status of their group, and this increases inaccordance with the desirability of their group tothem. In addition, SIDT argues that members whofeel some vulnerability about their position in adesirable group typically display increased ingroupbias and outgroup negativity in order to contributeto the ingroup’s status, as well as to strengthen theirown acceptability to the group members. Consistentwith SIDT’s position are findings from research onchildren’s peer group rejection [Nesdale et al., 2007],as well as a number of studies on adults’ intergroupattitudes [Jetten et al., 2002; Noel et al., 1995;Schmitt and Branscombe, 2001].On this basis, it was expected that children who

were assigned to a desirable new group in thecontext of an intergroup competition in this studywould display enhanced liking for their ingroup, aswell as aggression intentions toward outgroupmembers, in support of their group. However, giventhat the present context did not involve explicit andintentional confrontation or threat from an out-group [Dodge et al., 1984; Rule and Duker, 1973], itwas predicted that the children would display more

indirect than direct aggression intentions, becausethe former might be perceived to have less seriousconsequences.

Group Norms and Aggression

If peer group membership has such a potential toinfluence group members, it might also be antici-pated that this effect would be most stronglyrevealed via the influence of group norms. However,although research has shown that children’s atti-tudes toward ingroup and outgroup members areinfluenced by their group’s norms [Abrams et al.,2003, 2004; Nesdale et al., 2005b], scant research hasassessed the effects on children of a peer group normof aggression. Specifically, how might group mem-bers react if they happened to find themselves in agroup that, among other interests and activities, alsohad an aggressive norm (i.e., an expectation thatgroup members would, on occasion, engage in directand/or indirect aggression toward outgroup mem-bers or individuals)?Leaving aside groups of children who have drawn

together because of the members’ shared interest inaggression and violence [Duffy and Nesdale, 2009a;Rubin et al., 1998], there appear to be at least twopossible reactions that individuals might display insuch a situation. One possibility is that, given theimportance to children of gaining and retaininggroup membership, the children’s liking for theingroup would be unaffected by the group’s aggres-sion norm, and that they would simply conform tothe norm when it happened to be salient in aparticular situation.Consistent with this approach is research indicat-

ing the positive impact of classroom norms (i.e.,those held by most or all members of a class) onchildren’s aggressive attitudes and behavior [e.g.,Henry, 2001; Henry et al., 2000; Salmivalli andVoeten, 2004; Stormshak et al., 1999]. Other studieshave also reported that aggressive behavior wasviewed more positively by other group memberswhen the aggression was normative vs. nonnorma-tive [Boiven et al., 1995; Wright et al., 1986]. Inaddition, Nesdale et al. [2008] found that partici-pants’ attitudes toward the ingroup were unaffectedby whether the ingroup had a norm of outgroupdislike or liking, but that their bullying intentionswere greater when the ingroup had a norm ofoutgroup dislike vs. outgroup liking. Viewedtogether, these findings provide some grounds foranticipating that a peer group norm of aggressionmight prompt aggressive behavior from ingroupmembers.

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However, a plausible alternative prediction is thatchildren’s liking for the ingroup, and the extent towhich they would be likely to conform to theaggression norm, might be influenced by otherfactors in the situation. One such factor might betheir increasing awareness that aggression is typi-cally considered unacceptable by teachers andparents. Thus, according to this view, and especiallywith increasing age, children might actually expressless liking for, and less conformity to, an ingroupwith a norm of aggression.There is also evidence consistent with this predic-

tion. For example, research shows that, as childrenincrease in age, they do have an increasing aware-ness that negative attitudes and behaviors such asintergroup prejudice, aggression, and bullying areviewed as unacceptable and inappropriate byteachers and parents [e.g., Brown and Bigler, 2004;Greenwald and Banaji, 1995; Killen et al., 2001;Rutland, 1999; Rutland et al., 2005; Theimer et al.,2001]. In addition, from school-age onwards,children show an increasing understanding of, andtendency to engage in, self-presentational behaviorthat puts them in the best possible light, especiallywhen they are being observed by adults [e.g., Aloise-Young, 1993; Banerjee, 2002; Banerjee and Yuill,1999; Bennett and Yeeles, 1990; Rutland, 1999;Rutland et al., 2005].In sum, although there is evidence consistent with

both predictions concerning the possible effect ofaggressive group norms on children’s aggression, noresearch has assessed these possibilities directly.Accordingly, this was a major aim of the presentresearch. In order to address this issue experimen-tally (i.e., by systematically manipulating the pre-sence or absence of group norms of aggression), yetin an ethically responsible manner, the study focusedon the impact of group norms on children’saggressive intentions, rather than their actualaggressive behavior. Thus, participants in this studywere assigned to one of three groups (no groupnorm, norm of indirect aggression, or norm of directaggression), and their subsequent aggressive inten-tions were compared, together with their liking fortheir ingroup.

Emotional Empathy and Children’s Aggression

Another major issue addressed in this studyrelated to the critical problem of identifying situa-tional and individual factors that might mitigate oreradicate children’s aggressive behavior. Emotionalempathy, defined as the ability to experience thesame feelings as those of another person in response

to a particular situation [Nesdale et al., 2005b], isone individual difference factor that might play animportant role in determining young children’saggressive intentions and behaviors toward out-group members.Research has shown that children tend to display

empathy from an early age, even as early as thepreschool years [Eisenberg et al., 1990; Radke-Yarrow et al., 1983], that increasing empathy canprompt a child to feel compassion or sympathy foranother [Miller et al., 1996], and that increasingempathy is associated with increased pro-social orhelping behavior [Eisenberg et al., 1990; Krevansand Gibbs, 1996; Litvack-Miller et al., 1997;Roberts and Strayer, 1996; Strayer and Roberts,2004; Warden and Mackinnon, 2003]. On this basis,it is plausible that more empathic children might beless likely to develop aggressive intentions, or engagein aggressive behavior and, if so, that enhancingchildren’s empathy might comprise a useful strategyfor tackling school aggression.A number of studies have examined the relation-

ship between empathy and aggression, although thefocus has typically been on adolescents and pre-adolescents. However, although some support hasbeen found for an empathy–aggression relationship[e.g., Kaukiainen et al., 1999], as well as for alinkage between empathy and bullying [e.g., Wardenand Mackinnon, 2003], the findings have been lessclear-cut in other studies [e.g., Endresen andOlweus, 2001; Gini et al., 2007; Jolliffe andFarrington, 2006]. Given that empathy emerges inchildren at such a young age, another important aimof this study was to assess the relationship betweenempathy and aggressive intentions in youngchildren.

Simulation Paradigm

To address the preceding issues, the studyemployed a variant of the intergroup simulationparadigm that has been used in a number of studieson the development of children’s ethnic prejudice[e.g., Nesdale et al., 2003, 2005c], as well as onchildren’s bullying [Nesdale et al., 2008]. The essenceof this paradigm is that participants are randomlyassigned membership in a group and are asked torole-play participating against another group in apurported intergroup competition. Although theirgroup, and their membership in it, has only a briefexistence, participants’ reactions (i.e., attitudes,beliefs, behavior intentions) can be examined inrelation to the ingroup, as well as the outgroup. Inparticular, these reactions can be examined under

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varying conditions of ingroup membership (e.g.,group norms, group membership position), as wellas intergroup relations (e.g., outgroup threat), andother situational contexts. Moreover, the fact thatthe paradigm allows for the manipulation ofvariables relating to the ingroup, the outgroup,and the context, enables causal inferences to bedrawn, an advantage that is not afforded tocorrelational designs.Most importantly, however, the findings revealed

in these minimal group studies are remarkablysimilar to research findings obtained in studieswhere children have been randomly assigned togroups in a naturalistic setting, and the effects of thegroup assignments have been observed over a periodof days or weeks [e.g., Bigler, 1995; Bigler et al.,1997; Sherif et al., 1961]. This similarity confirms theexternal validity of findings relating to children’singroup membership and its effects that are revealedusing the simulation group paradigm.

This Study

This study used a simulation group paradigm toinvestigate children’s intergroup attitudes and theirreadiness to adopt direct and indirect aggressiveintentions toward outgroup members, as a functionof their peer group norms (i.e., whether the ingrouphad a norm of indirect or direct aggression towardoutgroup members, or no aggression group norm).The study also examined the extent to whichchildren’s empathy was related to their aggressionintentions.The participants in the study were 6 and 9-year-

old boys and girls. These participants were chosenbecause of the currently mixed pattern of findingsconcerning, on the one hand, the incidence of directcompared with indirect aggression as childrenincrease in age and, on the other hand, the incidenceof these forms of aggression by boys vs. girls. Thus,some studies have reported that more direct aggres-sion than indirect aggression is displayed by childrenat a younger age [e.g., Bjorkqvist and Lagerspetz,1992], whereas other studies have yielded no suchdifference [Crick et al., 1997, 2006; Ostrov andCrick, 2007]. Similarly, some studies have reportedthat girls display more indirect vs. direct aggression,whereas boys do the reverse [Crick et al., 1997, 2006;Ostrov and Crick, 2007], while other studies havenot found this effect [e.g., Atlas and Pepler, 1998;Galen and Underwood, 1997; Little et al., 2003; Rysand Bear, 1997; Salmivalli and Kaukiainen, 2004;Tomada and Schneider, 1997]. Including 6 and

9-year-old boys and girls as participants in this studyallowed for a re-examination of these issues.

METHOD

Participants

The sample comprised 161 white Anglo-Austra-lian boys and girls, with 80 (42 boys, 38 girls) fromgrades 1, 2, and 3 (M5 6.45 years, SD5 0.83 years)and 81 (37 boys, 44 girls) from grades 4, 5, and 6(M5 9.51 years, SD5 0.86 years). The childrenattended a primary school serving a lower middleclass community and participation was voluntary.Permission to participate was sought from theparents of all the children in grades 1–6 at theschool. Parents were informed that the childrenwould be asked to role-play their participation inseveral groups. The children who participated in thestudy had the written consent of their parents, andgave their own verbal consent. None declined toparticipate.

Design

The study had a 2 (age: 6 vs. 9 years)� 2 (gender:male vs. female)� 3 (group norm: direct aggressionvs. indirect aggression vs. no aggression norm)factorial between-subjects design. Within age andgender, participants were randomly assigned to thegroup norm conditions, with approximately equalnumbers of boys and girls in each condition.Participants subsequently rated their attitudes to-ward the ingroup and the outgroup, and revealedtheir indirect and direct aggression intentionstoward an outgroup member in a series of vignettes.

Materials

Photos: The set of photos used in the study wasdrawn from a pool of photos that has beendeveloped and pretested by the authors, as detailedin a previous report [Nesdale et al., 2003]. Withinage and gender, the head-and-shoulder color photoswere of Anglo-Australian children, who werematched for expression (not smiling) and attractive-ness (moderate), following a pilot study with similaraged children to rate these attributes. Each photowas 150mm� 110mm and pasted onto a200mm� 200mm white cardboard square. A boardwas used to display the photos to the children in thestudy.Response booklet: A response booklet containing

the measures was prepared for each participant. Thebooklet included a series of questions, each with an

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accompanying 5-point unipolar or bipolar scale.Each scale comprised five pictures of animals orfaces that were graded in size from the smallest tothe largest (unipolar scale), or withthe largest pictures at the two end points and thesmallest in the middle (bipolar scale). The responseoptions on the unipolar scales typically ranged from1 (a small amount of the attribute) to 5 (a largeamount of the attribute). The response options on thebipolar scales typically ranged from 1 (a negativeresponse) to 3 (a neutral response) to 5 (a positiveresponse). Each point on each scale was labelledappropriately.Empathy: Participants’ empathy was measured

using a modified version of Bryant’s [1982] Index ofEmpathy for Children and Adolescents. Rather thanusing the full 22-item Bryant scale, a short versionwas used that had been developed by the authors inearlier research [Nesdale et al., 2005b]. The shortversion had eight items (e.g., I get upset when I see aboy or girl being hurt; Seeing a kid who is cryingmakes me feel like crying; I feel upset when I see a kidbeing punished by a teacher), in order to reducethe load on the participants. In addition, ratherthan using Bryant’s forced choice response formaton each item, the short version had a 5-pointunipolar scale for each item, that ranged from 1(not at all) to 5 (a lot), with each point on theunipolar scale marked by a picture of an animal.Further details of the changes to the items andresponse measures, and the psychometric propertiesof the shortened scale, are provided in Nesdale et al.[2005b]. As used in this study, the scale had aCronbach a of .68.

Group Norms Manipulation Check

To evaluate the success of the group normmanipulation, the participants were asked twoquestions, How much does your team like to teaseothers, or even push others or take their things? and,How much does your team like to tell stories aboutothers and get them left out of games and activities?The participants responded to both questions onseparate unipolar scales ranging from 1 (Not at all)to 5 (A lot).

Ingroup and Outgroup Attitudes

The participants’ attitudes toward members of theingroup and outgroup were measured by summingtheir responses on three separate scales that weredesigned to index their affect toward the members ofthe ingroup, as well as to the members of theoutgroup. Participants were asked to indicate how

much they liked the members of their own team,(How much do you like the children in your team?), aswell as the members of the other team (How much doyou like the children in the other team?), on separatebipolar scales ranging from 1 (I don’t like them at all)to 5 (I like them a lot). Similarly, the participantswere asked to indicate how much they trusted themembers of their own team (How much do you trustthe other children in your team?), and the other team(How much do you trust the children in the otherteam?), on separate bipolar scales ranging from 1(I don’t trust them at all) to 5 (I trust them a lot).Finally, the children were asked how much theywould like to play with the members of their ownteam (How much would you like to play with thechildren in your team?), as well as the other team(How much would you like to play with the children inthe other team?), on separate bipolar scales rangingfrom 1 (I wouldn’t like to play with them at all) to 5(I would like to play with them a lot). Thus, eachparticipant received two summed scores, one for theingroup and one for the outgroup. Each score couldrange from 3 to 15. The summed scales (i.e., liking,trust, play) had a Cronbach’s a of .79 for theingroup and .84 for the outgroup.

Aggression Intentions

The participants’ intentions to engage in directand indirect aggression were measured on a scaledevised by Duffy and Nesdale (2009b). Participantsresponded to four vignettes, each of which describedan incident on the day of the drawing competition inwhich the participant was to be involved (seeProcedure below). The purpose of the vignetteswas to provide participants with hypotheticalsituations that would allow them to give a directand/or indirect aggression response, if this was theirintention. For example, one vignette described thefollowing situation,

Today is the day of the drawing competition. Youarrive at the school where the competition is beingheld and find the other members of your team. Youall sit down at the table you will be working at. Nextto you is the other team’s table. No-one is there yet.As the starting time for the competition gets closer,you see one of the members of the other team arrive.(Researcher points to photo of one member ofoutgroup.) After sitting alone for a few minutes, thechild from the other team looks at your team andsays, ‘‘hullo’’.Each vignette was accompanied by four responses.

One of the responses was consistent with the

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earlier characterization of direct aggression (e.g.,name-calling, taking things from another, hitting,pushing, or teasing another); another response wasconsistent with the earlier characterization ofindirect aggression (e.g., ignoring, gossiping about,deceiving, rejecting, or excluding another). Forexample, the direct aggression response to thevignette above specified: Say something mean aboutthe other team, whereas the indirect aggressionresponse specified: Ignore the person who said hulloand keep talking to your team. The other tworesponses were included as filler items and describedmildly prosocial acts (e.g., Ask them to come and sitwith your team until someone from their teamarrives). These items were included so as to reducethe focus on the aggression items. The participantwas asked in relation to each response, How likely isit that you would (give this response; e.g., saysomething mean about the other team?), with eachresponse being given on a 5-point bipolar scale,ranging from 1 (Very unlikely I would do this) to 5(Very likely I would do this), with each point on thescale labelled appropriately.The remaining three vignettes dealt with an out-

group member being upset with his drawing, anoutgroup member spilling his pencils on the floor, andan outgroup member asking to join in a game with theingroup members. All participants responded to allfour responses accompanying each vignette. Theparticipant worked his/her way through the fourvignettes, each of which had a different set of fourresponses, but each of which included a directaggression response, an indirect aggression response,and two filler items, each of which related to thecontent of the particular vignette.The designation of the particular response items as

instances of direct vs. indirect aggression was basedon an earlier study in which a factor analysis of theitems revealed two factors accounting for 64.73% ofthe variance, with Direct Aggression accounting for56.48%, and Indirect Aggression accounting for8.25%, of the total variance (Duffy and Nesdale,2009b). The loadings of the four Direct Aggressionitems used in this study ranged from .68 to .91, andthe loadings of the four Indirect Aggression itemsranged from .60 to .93. Each of the subscalesdisplayed good internal consistency, with Cronbach’sa coefficients for the Direct Aggression and IndirectAggression scales being .85 and .74, respectively. Theaggressive intentions measure has now been usedsuccessfully in several studies with young children[e.g., Duffy and Nesdale, 2009b; Nesdale et al., 2008].In this study, participants’ scores on Direct and

Indirect Aggression were the sum of their responses

to the relevant response measure on each of the fourvignettes. Thus, each participant received twosummed scores, one for Direct Aggression and onefor Indirect Aggression, with each score rangingfrom 4 to 20.

Procedure

All students from years 1 to 6 in the participatingschool were asked by their teachers to draw a pictureof themselves on a 145mm� 210mm piece of paper.The children were told that next week some visitorswould look at their drawings, if their parents hadgiven permission for them to participate. One weeklater, the children with parental permission weretested individually away from the classroom in aquiet place. After establishing rapport with thechild, the researcher ensured that each participantwas comfortable with using the unipolar and bipolarscales by having the participant complete severalpractice questions. Participants were then asked tocomplete the revised emotional empathy scale.Participants were then asked to pretend that they

were going to participate in an intergroup drawingcompetition that would involve children from otherschools in the area. They were told that they wouldbe introduced to their own team members, and thento the members of the other team. With theparticipant’s agreement, an instant head-and-shoulders photo was then taken of him/her.The participants were then shown (randomly

selected) photos of the other two same age andgender members of their team, displayed on a board.To enhance their ingroup identification, they wereasked to pin their own photograph on the boardbetween the photos of the other team members. Theparticipant was also told that the other membershad given him/her the opportunity to select a colorname (e.g., red, blue) for the team. Once theparticipant indicated his/her choice, the color labelwas written beside the team photos.In addition, to simulate the typical situation where

group members who engage in aggression typicallydo so against individuals who have lower strength,status or power [Ojala and Nesdale, 2004], the statusof the ingroup was enhanced in comparison with theoutgroup. Thus, each participant was told that allthe children’s drawings in their team had beenjudged by an artist who had considered theirdrawings to be excellent and hence they had beenput into the same team. Their team was alsoawarded a gold star to emphasize the quality of itsperformance, and this was attached to the boardnext to the photos of the team members.

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To manipulate group norms, participants in thedirect aggression condition were then told that,‘‘yfrom talking to the kids in your team, it seemsthat they don’t like kids from other teams. If they getthe chance, they like to tease them, or even push themor take their things. If you want to stay in this newteam that you have just joined, then you will have todo the same things as the other members.’’ Incontrast, participants in the indirect aggressioncondition were told that, ‘‘yfrom talking to thekids in your team, it seems that they don’t like kidsfrom other teams. If they get the chance, they like totell stories about them, and to get them left out ofgames and activities. If you want to stay in this newteam that you have just joined, then you will have todo the same things as the other members.’’ Finally,participants in the no aggression norm groupcondition were given no information about thenorms of their new group.Following this, the experimenter revealed the

photos of the same age and gender members of theother team and the participant was asked to have agood look at the other team. To complete the statusmanipulation, the children were then informed thatthe members of the other team were judged to begood drawers, but your team’s drawings were betterthan their drawings.The participants were then directed to their

response booklet and responded to the questionsin the booklet, with the researcher assisting theyounger children by reading the questions, wherenecessary. The participants completed the two groupnorm manipulation check questions, followed by theingroup and outgroup attitude questions (i.e., like,trust, and play in relation to both the ingroup andthe outgroup). To reduce the focus on the maindependent measures, some of the items were filleritems that were interspersed through the other items.The filler items fitted with the general thrust of thequestions but were not central to the main focus ofthe study (e.g., How much do you think you are thesame or different to the other children in your team?).Finally, the participants responded to the fourvignettes designed to measure their intentions toengage in direct and indirect aggression.When the participants had completed the response

measures, the children’s participation in the gamewas discussed with them. Care was taken to ensurethat each participant understood that s/he hadparticipated in a game of pretence, and that his/her participation in the game was greatly appre-ciated. The researcher also took the opportunity tocheck with each child his/her understanding of theschool’s attitude toward aggression and bullying. All

children indicated that the school was very opposedto this sort of behavior. The children were thengiven their own photos, thanked for their participa-tion, and returned to their classrooms.

RESULTS

Group Norms Manipulation Check

To evaluate the success of the group normsmanipulation, participants responded to two ques-tions, How much does your team like to tease others,or even push others or take their things? (i.e., directaggression norm) and How much does your team liketo tell stories about others and get them left out ofgames and activities? (i.e., indirect aggression norm).Responses to these questions were analyzed inseparate one-way analysis of variances (ANOVAs),each with three levels of group norms (directaggression vs. indirect aggression vs. no aggressionnorm/control). Analysis of the responses on thedirect aggression norm item revealed a significanteffect for group norms, F(2, 159)5 35.16, Po.001,Z2 5 .31. Comparison of the cell means usingDuncan’s Multiple Range Test (Po.05) indicatedthat the direct aggression norm was endorsedsignificantly more by the direct aggression normgroup (M5 3.33) than the indirect aggression normgroup (M5 2.17), which endorsed the norm sig-nificantly more than did the no aggression norm/control group (M5 1.28). Similarly, analysis of theresponses on the indirect aggression norm item alsorevealed a significant effect for group norms, F(2,159)5 17.72, Po.001, Z2 5 .18, indicating that theindirect aggression norm was endorsed significantlymore by the indirect aggression norm group(M5 3.57) than the direct aggression norm group(M5 2.98), which endorsed the norm significantlymore than did the no aggression norm/controlgroup (M5 1.91). These findings indicated thatboth the direct and indirect aggression norms weresuccessfully manipulated.

Ingroup and Outgroup Attitudes

The participants’ summed scores on the liking,trust, and willingness to play scales were analyzed in a2 (participant age: 6 vs. 9 years)� 2 (participantgender: male vs. female)� 3 (group norm: directaggression vs. indirect aggression vs. no groupnorm)� 2 (target group: ingroup vs. outgroup)ANOVA, with repeated measures on the last factor.This analysis revealed three significant effects, includ-ing a main effect for target group, F(1, 149)599.38,

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Po.001, Z25 .40, which indicated that the partici-pants had significantly more positive attitudes towardthe ingroup (M511.46, SD5 2.95) than the out-group (M5 8.21, SD53.19).This effect was qualified by a significant

age� target group interaction effect, F(1,149)5 15.45, Po.001, Z2 5 .09. Comparison of thecell means using Duncan’s Multiple Range Test(Po.05) indicated that, at both ages, the partici-pants were significantly more positive toward theingroup vs. the outgroup. However, the difference inliking for the ingroup vs. the outgroup was greaterfor the younger children (M5 12.08, SD5 2.78;M5 7.51, SD5 3.49, respectively) than theolder children (M5 10.85, SD5 3.00; M5 8.90,SD5 2.71, respectively).Finally, the analysis revealed a significant main

effect for group norms, F(2, 149)5 3.91, Po.05,Z2 5 .05. Compared with the control condition(M5 10.49, SD5 2.50), the participants liked theingroup (and outgroup) members less in both theindirect aggression norm condition (M5 9.30,SD5 3.25) and the direct aggression norm condition(M5 9.70, SD5 3.28). Analysis of the cell meansusing Duncan’s Multiple Range Test indicated thatthe former difference was greater than the latter, butthat there was no difference in ingroup liking as afunction of whether the ingroup had a direct vs.indirect aggression norm.

Direct and Indirect Aggression Intentions

The participants’ direct and indirect aggressionintention scores were analyzed in a 2 (participantage: 6 vs. 9 years)� 2 (participant gender: male vs.female)� 3 (group norm: direct aggression vs.indirect aggression vs. no group norm)� 2 (aggres-sion type: direct vs. indirect) ANOVA, with repeatedmeasures on the last factor. This analysis revealedfour significant effects. There was a significant maineffect for aggression type, F(1, 149)5 190.31,Po.001, Z2 5 .56, which indicated that the partici-pants expressed greater indirect (M5 10.27,SD5 3.88) than direct aggression intentions(M5 6.32, SD5 2.91). The analysis also revealed asignificant effect for participant age, F(1,149)5 39.03, Po.001, Z2 5 .21, which showed thatthe direct and indirect aggressive intentions of the6-year-old participants (M5 9.58, SD5 3.70) weregreater than the 9-year-old participants (M5 7.02,SD5 2.42).The preceding effects were qualified by a signifi-

cant participant age� aggression type interac-tion effect, F(1, 149)5 13.53, Po.001, Z25 .08.

Comparison of the cell means indicated that, at bothages, the participants expressed greater indirect thandirect aggression intentions. However, the resultsindicated that the difference in indirect vs. directaggression intentions was greater for the 6-year-old(M5 12.10, SD5 4.09; M5 7.06, SD5 3.32, respec-tively) than for the 9-year-old participants (M5

8.47, SD5 2.65; M5 5.58, SD5 2.22, respectively).To determine that participants actually did have

aggression intentions, each mean in the aboveinteraction was also compared with the score (i.e.,a summed score of 4) relating to the response optionindicating that indirect or direct aggression was veryunlikely (i.e., Very unlikely I would do this), in fourseparate one-sample t-tests. These results indicatedthat, for the 6-year-old participants, the means forindirect and direct aggressive intentions (M5 12.10,M5 7.06, respectively) were both significantly great-er than the zero aggression response, ts (79)5 18.37,Po.001; 8.31, Po.001, respectively. Similarly, theresults for the 9-year-old participants indicated thatthe means for indirect and direct aggressive inten-tions (M5 8.47, M5 5.58, respectively) were alsoboth significantly greater than the zero aggressionresponse, ts (80)5 15.15, Po.001; 6.41, Po.001,respectively. These findings revealed that the parti-cipants did express aggressive intentions, at each agelevel, and in relation to both indirect and directaggression intentions. However, in absolute terms,the participants’ aggression intentions were stillcomparatively low (ranging from 5.58 to 12.10 ona summed 20-point scale).The analysis also revealed a significant participant

age� group norm interaction effect, F(2, 149)5 3.23,Po.05, Z2 5 .04. As indicated in Table I, compar-isons of the cell means revealed that, compared withthe no aggression norm condition, the direct andindirect aggression group norms did not instigategreater aggression intentions in either the 6-year-old(no aggression norm M5 8.87 (SD5 3.34), directaggression norm M5 9.41 (SD5 3.90), indirectaggression norm M5 10.46 (SD5 3.74)), or the9-year-old participants (no aggression norm

TABLE I. Means for Participant Age�Group Norm Interaction

Effect on Children’s Aggression Intentions

Group norm

Participant age Control Indirect aggression Direct aggression

6 years 8.87bcd� 10.46d 9.41cd

9 years 7.02ab 6.40a 7.57abc

�Cell means that do not share the same subscript are significantlydifferent, Duncan’s Multiple Range Test, Po.05.

251Group Norms and Aggression

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M5 7.02 (SD5 2.24), direct aggression normM5 7.57 (SD5 2.76), indirect aggression normM5 6.40 (SD5 2.04)). From another perspective,the analysis indicated that although the 9-year-oldparticipants displayed less aggression than did the 6-year-olds in each of the aggression norm conditions,the difference was greater in the indirect aggressionnorm condition than in the no aggression norm anddirect aggression norm conditions.Finally, the analysis did not reveal any significant

main or interaction effects on the participants’aggressive intentions involving participant gender.

Empathy and Aggression

Several analyses were also carried out to examinethe predictive significance of participants’ empathyfor their aggressive intentions. First, the Pearsoncorrelation coefficients between these variables, aswell as with age, are recorded in Table II. Asindicated in this table, the results revealed thathigher empathy scores were related to lower, directaggression intentions (�.21), whereas empathy wasunrelated to indirect aggression intentions (�.06).Further, compared with younger children, olderchildren had lower indirect (�.47) and direct (�.25)aggression intentions. In view of these findings, twohierarchical multiple regression analyses were car-ried out to assess the predictive significance of theparticipants’ empathy in relation to both their directand indirect aggression intentions.Empathy and direct aggression intentions: Scores

on participant age were entered at Step 1 (as dummyvariables), followed by empathy (transformed into z-scores) at Step 2, followed at Step 3 by the entry ofscores on the age� empathy interaction. Theregression analysis revealed that, in Step 1, theequation was significant, F(1, 157)5 12.20, Po.001,and accounted for 7% of the variance in children’sdirect aggression intentions. Older child age(b5�.27, Po.001) was associated with lower directaggression intentions. In Step 2, the equation wasalso significant, F(2, 156)5 10.67, Po.001, with theaddition of empathy accounting for an additional

5% of the variance (Fchange (1, 156)5 8.56,Po.005). Consistent with expectations, empathy(b5�.22, Po.005) was a significant predictor ofdirect aggression, together with children’s age(b5�.29, Po.001). The analysis revealed that noadditional variance was accounted for by theage� empathy interaction in the final step.Empathy and indirect aggression intentions: The

same multiple regression analysis, incorporatingthe same steps, was carried out in relation to theparticipants’ indirect aggression intentions. Thisregression analysis revealed that, in Step 1, theequation was significant, F(1, 157)5 47.82, Po.001,and accounted for 23.3% of the variance inchildren’s indirect aggression intentions. Older childage (b5�.48, Po.001) was again related tosignificantly lower direct aggression intentions.However, the analysis revealed that there was nofurther significant change in the subsequent steps;that is, empathy was not a significant predictor ofthe participants’ indirect aggressive intentions(b5�.07, P5 .306), nor was there a significantage� empathy interaction.

DISCUSSION

This study investigated 6 and 9-year-old children’sintergroup attitudes and their readiness to adoptdirect and indirect aggressive intentions towardoutgroup members, as a function of their member-ship in a social group that did, or did not, have agroup norm of indirect or direct aggression towardoutgroup members. In addition, the study examinedthe extent to which children’s empathy was relatedto their aggression intentions.

Group Membership, Intergroup Attitudes, andAggression Intentions

As expected, the results indicated that, in thecontext of an intergroup competition, membershipin a particular social group was significantly relatedto both the participants’ intergroup attitudes andtheir aggression intentions. Specifically, a target

TABLE II. Pearson Correlation Coefficients Computed Between Participants’ Age, Empathy, Indirect Aggression and DirectAggression Scores (n5 161)

Age Empathy Indirect aggression Direct aggression

Age –

Empathy �.08 –

Indirect aggression �.47�� �.06 –

Direct aggression �.25�� �.21�� .41�� –

��Correlation is significant at the .01 level (two-tailed).

252 Nesdale et al.

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group main effect on intergroup attitudes indicatedthat the participants had very positive attitudestoward their ingroup, which were also significantlymore positive than their attitudes toward theoutgroup. Further, this preference for the ingroupover the outgroup was revealed at each age level inthe significant target group� age interaction effecton intergroup attitudes, although the difference wasgreater for the younger children. Importantly, thesefindings are consistent with field experiments inwhich group membership was also systematicallyvaried, but lasted for days or weeks [e.g., Bigler,1995; Bigler et al., 1997; Sherif et al., 1961], as wellas with other research using a group simulationparadigm [e.g., Nesdale et al., 2003, 2005a,b].Consistent with their intergroup attitudes, the

results also indicated that the participants displayedenhanced levels of both direct and indirect aggres-sive intentions toward the outgroup. This pattern ofresults fits with SIDT [Nesdale, 2004, 2007], whichargues that individuals who identify with a parti-cular group are likely to engage in behaviors thatenhance, maintain, or defend the status of theirgroup in situations of competition or conflict, as wasthe case in this study. That said, given that thepresent context did not involve explicit and inten-tional confrontation or threat from outgroupmembers [Dodge et al., 1984; Rule and Duker,1973], it was not surprising that an aggression typemain effect on aggression intentions was alsorevealed. This finding indicated that the childrendisplayed more indirect than direct aggressionintentions, the former most likely being perceivedto have less serious consequences. Moreover, asignificant aggression type� age interaction effectindicated that this was true of both the younger andolder participants, although the difference wasgreater for the younger participants.

Group Norms, Intergroup Attitudes, andAggression Intentions

An issue of particular importance in this studyconcerned the potential effect on group members’intergroup attitudes and outgroup aggression inten-tions of their group having an aggression norm,either of direct or indirect aggression. It will berecalled that, based on previous findings, thereappeared to be two plausible predictions that couldbe made about the possible effects of such norms.On the one hand, it was possible that an ingroupnorm of aggression would impact directly on thegroup members’ aggressive intentions, but not ontheir ingroup liking. On the other hand, it was

possible that children would like an ingroup with anorm of aggression less, and that such a norm wouldnot increase, and might even decrease, their ten-dency toward aggressive intentions, especially forolder children.Consistent with the latter prediction, the findings

revealed a significant group norm main effect onintergroup attitudes. This effect indicated that,compared with the no group norm condition, theparticipants liked their ingroup less when it had anorm that endorsed either indirect or direct aggres-sion. Moreover, this finding was not qualified byeither age or gender—apparently, this was the viewof participants of both ages and both genders. Thisresult is of considerable importance because itsuggests that there are limits to the extent to whichyoung children will express positivity toward aningroup. One such limit is apparently to be found inthe particular attitudes and behaviors that might beendorsed by a particular group. In the present case,the participants’ ingroup liking was clearly dimin-ished by the group’s endorsement of direct andindirect aggressive behavior. In contrast, previousresearch that has manipulated other ingroup normshas invariably reported that ingroup liking wasunaffected by the norm endorsed by the ingroup[e.g., Nesdale et al., 2005c, 2008].Importantly, and again consistent with the second

prediction above, the findings also yielded asignificant group norm� participant age interactioneffect on aggression intentions. This effect indicatedthat although the older children tended to displayfewer aggression intentions than the younger chil-dren, especially in indirect aggression, the aggressiongroup norms did not actually relate to the aggressiveintentions of either the 6 or 9-year-old children.That is, at both ages, the children in the indirect anddirect aggression norm conditions did not displaymore indirect and direct aggressive intentions,respectively, than did the children in the groupwithout an aggression norm.The most immediate explanation for this finding,

of course, is that the group aggressive normmanipulations were simply ineffective. Against this,however, are the findings on the manipulation checkitems indicating that the norm manipulation workedexactly as intended. Thus, compared with partici-pants in the no aggression norm condition, partici-pants in the direct aggression norm conditionindicated that their group endorsed this type ofbehavior, whereas participants in the indirectaggression norm condition indicated that theirgroup endorsed indirect aggression. In addition, aswe have seen, the findings on the intergroup attitude

253Group Norms and Aggression

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measure revealed that the group norm manipula-tions were significantly related to the participants’attitudes toward their ingroup (and the outgroup).That is, the group members liked their group lesswhen it had an aggression norm, compared withwhen it had no such norm. In addition, as notedearlier, previous research on peer groups using thesame minimal group paradigm with a similar type ofnorm manipulation revealed that group membersshowed considerable conformity to group normsthat emphasized inclusion vs. exclusion of nongroupmembers [e.g., Nesdale et al., 2005c], and dislike vs.liking for outgroup members [e.g., Nesdale et al.,2008]. Viewed together, these findings speak againstthe view that the group aggression norm manipula-tion in this study simply did not work.Rather, the most plausible explanation for the

present lack of an effect of group aggression normson aggression intentions appears to lie in the natureof the particular group norms that were manipu-lated in this study. In short, the pattern of resultssuggests that the participants were not especiallyhappy about being a member of a group with adirect or indirect aggression norm, and hence werenot prepared to conform to such an ingroup norm.Further, given that the participants displayed lowerdirect than indirect aggression intentions, and thatthe 9-year-olds displayed lower aggression inten-tions than did the 6-year-olds, the overall pattern offindings suggests that the participants were self-regulating their aggression intentions. Indeed, thisexplanation fits with other evidence, mentionedearlier, that with increasing age, children do havean increasing awareness that negative attitudes andbehaviors such as intergroup prejudice and aggres-sion are considered unacceptable and inappropriateby teachers and parents [e.g., Brown and Bigler,2004; Greenwald and Banaji, 1995; Killen et al.,2001; Rutland, 1999; Rutland et al., 2005; Theimeret al., 2001].Of course, this explanation does not account for

the findings, noted above, that classroom norms ofaggression influenced children’s aggression attitudesand behavior [Henry, 2001; Henry et al., 2000;Salmivalli and Voeten, 2004; Stormshak et al., 1999].However, it is entirely plausible that the fact that thenorm in these cases was held by a whole class of realrather than hypothetical peers, rather than by asmall group, resulted in the norm being endorsedand conformed to by the children in those studies.That is, a norm that is held by a whole class confersconsiderable authority and influence on that norm,compared with one that is held by only a smallgroup. Consistent with this, Henry [2001] reported

that the wider the range of acceptable aggressivebehavior in classes, the higher was the rate ofvictimization and aggression.In sum, the present pattern of findings is

consistent with the view that aggressive and violentchildren might seek out and like others who endorse,and engage in, aggressive and violent behavior[Duffy and Nesdale, 2009a,b; Rubin et al., 1998],whereas most other children would not. Presumably,their response reflects the opprobrium in which suchbehavior is held by significant others, such asparents and teachers. That said, it needs to beremembered that this study focused on aggressionintentions, rather than aggression per se.

Empathy and Children’s Aggressive Intentions

Another major issue addressed in this studyconcerned the possible relation between children’semotional empathy and their aggression intentions.As noted earlier, this issue has been addressed in anumber of studies, although most have focused onadolescents [e.g., Endresen and Olweus, 2001; Giniet al., 2007; Jolliffe and Farrington, 2006; Kaukiai-nen et al., 1999], rather than children in middlechildhood. The present findings indicated thatempathy was significantly negatively correlated withthe participants’ direct aggression intentions, butnot their indirect aggression intentions. Consistentwith this, hierarchical multiple regression analysesrevealed that the equation predicting direct aggres-sion involved two significant predictor variables: ageand children’s empathy. In contrast, age was theonly significant predictor in the equation predictingindirect aggression.There are several points to be made about these

findings. First, although previous research hasshown that empathy can facilitate pro-social beha-vior in young children [e.g., Eisenberg et al., 1990;Krevans and Gibbs, 1996; Litvack-Miller et al.,1997; Roberts and Strayer, 1996; Strayer andRoberts, 2004; Warden and Mackinnon, 2003], thepresent finding makes clear that greater empathy isassociated with lower direct aggression intentions.On this basis, there appear to be good grounds forfacilitating the development of empathy in youngchildren as one strategy aimed at reducing children’sdirect aggression intentions and, perhaps, theirdirect aggression.A second issue concerns the basis upon which the

empathy effect occurs. It is possible that empathymight result in a decrease in aggression intentionsbecause empathy simply conflicts with aggression, orbecause empathic children feel compassion or

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sympathy for the potential victims. Alternatively, itis possible that empathic children might be moresensitive to societal expectations and hence aremore prone to managing their behavior and givingmore socially acceptable (i.e., anti-aggression)responses. However, although the fact that theparticipants declined to conform to the groupaggression norms adds weight to the latter view,the present results do not provide any resolution tothis issue. Additional research will be required todetermine which explanation is correct.A final point concerns the fact that empathy

predicted the participants’ direct aggression inten-tions, but not their indirect aggression intentions.The most straightforward explanation for thisdifference is that it simply reflects a difference inthe severity of the behaviors involved in the twoaggression types, especially as perceived by childrenin middle childhood. That is, direct aggressionintentions may be considered to be more severebecause they involve a physical aspect (e.g., pushing,hitting, taking things) that indirect aggressionintentions do not. According to this view, the moresevere effects of direct aggression arouse and engageyoung children’s empathy, whereas the less severeeffects of indirect aggression do not. The presentfindings that both younger and older children weremore prepared to display indirect rather than directaggression intentions would appear to be consistentwith this view.

Age, Gender, and Children’s AggressiveIntentions

Contrary to some earlier findings, the participants’aggression intentions in this study were unrelated totheir gender. In particular, there was no participantgender� aggression type interaction effect on parti-cipants’ aggression intentions. Males did not engagein more direct vs. indirect aggression, with femalesdisplaying more indirect vs. direct aggression, asCrick and associates reported in their research withpreschool children [Crick et al., 1997, 2006; Ostrovand Crick, 2007]. Instead, at 6 years of age, bothboys and girls revealed the same amount of indirectaggression intentions and (a lesser amount of) directaggression intentions.Moreover, although Cairns et al. [1989] and

Bjorkqvist and Lagerspetz [1992] reported genderdifferences in types of aggression by 10 and 11 yearsof age, respectively, such was not the case with the9-year-old children in this study. Instead, consistentwith other research [e.g., Atlas and Pepler, 1998;Galen and Underwood, 1997; Rys and Bear, 1997],

the findings did not reveal more indirect aggressionintentions by girls than boys. Moreover, in thisstudy, the boys vs. girls did not reveal greater directaggression intentions, contrary to the results of someresearch [Cairns et al., 1989; Bjorkqvist andLagerspetz, 1992].One possibility, of course, is that the present

results reflect aggressive intentions, rather thanactual aggression. Alternatively, it might simply bethe case that the present findings add to the growingnumber of studies that question the claim that thereare clear-cut gender differences in the types ofaggression displayed by children [e.g., Atlas andPepler, 1998; Galen and Underwood, 1997; Littleet al., 2003; Rys and Bear, 1997; Salmivalli andKaukiainen, 2004; Tomada and Schneider, 1997]. Itseems that, on occasion, and in some situations,boys and girls might reveal differences in the types ofaggression intentions, and aggression, that theydisplay, but that this is not a gender universal [seealso Salmivalli and Kaukiainen, 2004].

CONCLUSIONS

Although the importance of the social context onchildren’s aggression has been pointed out by severalresearchers [e.g., DeRosier et al., 1994; Fraczek,1996; Kiesner et al., 2002; Salmivalli et al., 1998], ithas thus far received comparatively little researchattention. This study sought to address this over-sight and revealed that 6 and 9-year-old childrenassigned to a social group evidenced enhancedaggressive intentions in a competitive intergroupcontext. However, although previous research hasalso attested to the influence of social group normson children’s attitudes and behaviors, the presentresults indicated that children will sometimes resistconforming to group norms, at least when theyinvolve aggression. Although the basis for thisremains to be addressed in future research, onepossibility is that this may occur when ingroupnorms are contrary to the norms in the widercommunity and, perhaps, there is the possibility ofdetection by adults.The findings also revealed the important inhibiting

effect of emotional empathy on children’s direct, butnot their indirect, aggression intentions. Moreresearch will be needed to illuminate the basis ofthis difference, as well as the extent to which thepositive effects of emotional empathy can act as acounter-weight to children’s aggression intentions.Finally, this study suggests that the simulation

paradigm holds considerable promise as a technique

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for the experimental examination of children’saggressive intentions, if not their actual interperso-nal aggression. Of course, while this limitation hasinfluenced the nature of experimental research onchildren’s aggression since the earliest work byBandura et al. [1961, 1963], research with adults[e.g., Ajzen, 1991; Fox-Cardamone et al., 2000;Terry et al., 1993], as well as children [e.g., Crickand Dodge, 1994] has shown that behavior inten-tions have a demonstrated predictive significancefor actual behavior. Given the considerable impor-tance of the need to fully understand the instigationand inhibition of young children’s aggression, itwould seem that any approaches that have thecapacity to shed further light on this socialphenomenon would appear to be worthy of utiliza-tion by researchers.

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