PERFORMANCE INCOMPETITIVE ENVIRONMENTS: GENDER DIFFERENCES* URI GNEEZY MURIEL NIEDERLE ALDO RUSTICHINI Eventhough the provision of equal opportunities for men and women has beena priorityin manycountries, large gender differences prevail in competitive high-rankingpositions. Suggested explanations include discrimination and dif- ferencesin preferencesand human capital. In this paper we present experimental evidencein support of anadditionalfactor: women may be lesseffective than men incompetitive environments, even if they are able to perform similarly in non- competitiveenvironments. In a laboratoryexperiment we observe, as we increase thecompetitiveness of theenvironment, a signicant increasein performancefor men,but not for women. This results in a signicant gendergap inperformance intournaments, while there is no gap whenparticipants are paid according to piecerate. This effect is stronger when women have to compete against men than insingle-sex competitive environments: this suggests that women may be ableto performin competitiveenvironments per se. I. INTRODUCTION Allocationsacross genders of high prole jobs remain largely favorableto men, and area majorfactor in thegender gap in earnings.For example, Bertrand and Hallock[2001] found that only2.5 percentof the vehighestpaid executivesin alargedata setof U.S.rmsare women (for areviewon genderdifferences in wages,see Blau and Kahn [2000]). Thenumerous attempts to explain this fact can beclassi ed intotwo broad categories.The rstexplanation restson gender differences in abilities and pref- erencesand hencein occupationalself-selection [Polachek 1981]. Thesecond class ofexplanations relatesto discrimination in the workplace,which leads todifferential treatmentof men and womenwith equal preferencesand abilities [Black and Strahan 2001; Goldin and Rouse2000; Wennerås and Wold1997]. In this paper wepropose and experimentallytest an addi- tional explanation:women may be less effective than menin competitiveenvironments. This fact will reducethe chances of successfor women when they compete for new jobs, promotions, *Wethank Daniel Brodkey, StefanoDella Vigna, Gerhard Orosel,Nikita Piankov,Alvin Roth, Lise Vesterlund, and seminar participants at numerous universities.This work was nanciallysupported by theBinational Science Foun- dationand by the German Israeli Foundation. © 2003by thePresident and Fellowsof Harvard Collegeand theMassachusetts Institute of Technology. The Quarterly Journal ofEconomics, August 2003 1049 1050 QUARTERLY JOURNALOF ECONOMICS etc.Similar argumentscan be found in theevolutionary psychol- ogyliterature, 1 and evenin thepopular press.They also form the basis forthe recent wave of support forsingle-sex schooling. The basic argumentis that girls,when shielded fromcompetition with boys,have a higherchance of developingtheir skills and interests in science.Surprisingly, however,there has beenno direct experi- mentaltest of this assertion:in psychologicalresearch, gender differencesin competitionor attitudes toward competitionare hardly mentioned. 2 Totest whether men and womendiffer in theirability orpro- pensity toperform in competitiveenvironments, we run controlled experiments.They allow us tomeasure performance precisely, and toexclude any discriminationand any expectationof discrimination. Wehave groups of three men and threewomen perform the task of solvingcomputerized mazes. In thebenchmark treatment, the pay- off toparticipants depends onlyon their own performance: each one is paid axedpiece rate for every maze solved over a periodof fteen minutes.We nd nostatistically signicant genderdifference in performance.To study theeffect of competition, we use a tourna- ment:the size and compositionof the group and thetask are the sameas before,but nowonly the participant whosolves the largest numberof mazes is paid proportionallyto the output. The average performanceof men increases, while that ofwomen is notaffected. As aresult,men outperform women on average, and moreso than in thenoncompetitive environment. 3 Thetournament design differs fromthe piece rate condition in twoways: payment is uncertain,and it depends ontheperfor- manceof others. A possibleexplanation ofthe observed gender differenceis that womenare more risk averse, so that if effortis costly,the introduction of uncertainty into payments will affect menand womendifferently. 4 Weintroduce uncertainty without 1.In one of theimportant books of thistradition [Daly and Wilson 1988, p. 161],it is stated “ Intrasexualcompetition is far moreviolent among men than amongwomen in everyhuman society for which information exists.” 2.See for instance, the special issue PsychologicalSex Differences of the American Psychologist [March 1995],pages 145– 171. In this issue even the contributionof the social psychologist [David Buss, “ Originsthrough Sexual Selection,”pages 164 –168]never mentions different attitude to competition as a differenceamong genders. 3.In the noncompetitive treatment, men outperform women but not signi - cantlyso. The gender gap inaverage performance in mixed tournaments is signicant, and signi cantly higher than in thenoncompetitive treatment. 4.For the psychology literature see Byrnes, Miller, and Schafer [1999]. In general,the results seem mixed, with a possiblyhigher degree of risk aversion amongwomen. PERFORMANCEIN COMPETITIVE ENVIRONMENTS 1051 competitionin thenext treatment. Again, onlyone participant is paid (as in thetournament), but this participant is nowchosen at random.We do not ndstatistically signicant genderdifferences in this treatment,and thegender gap in performanceis lower than in thetournament. All theabove experiments were conducted in mixedgroups of threemen and threewomen. But womenmight perform differ- entlyin single-sexgroups than in mixedgroups. As mentioned above,this argumentis usedto support single-sexschools or classes.The basic argumentis that girls in asingle-sexenviron- menthave a higherchance of developingtheir skills and interests in science.Two main types ofreasoning may support this.The rstis that if girls areless inclined to compete than boys,the environmentin single-sexschools for girls mightbe less competi- tivethan in mixedsex schools, and hencebe more suitable for girls.The second argument is that girls do notdislike competi- tion:they only do notcompete against boys.Hence, in single-sex schoolsgirls will bemore competitive, and educationmore effec- tivethan in mixedschools. 5 Todiscernthe effect of competitionper se on theperformance ofwomen, we measure the performance of women and menin single-sextournaments. We conduct tournaments as before,ex- ceptthat noweach group of six competitorsconsists of either only womenor only men. We nd that theperformance of women is signicantly higherin single-sextournaments than in thenon- competitivetreatment. Hence there are competitive environ- mentsin whichwomen’ s performanceincreases. Furthermore, thegender gap in performanceis notdifferent fromthe one in noncompetitiveenvironments and issmallerthan thegender gap in mixedtournaments. Whydo we observethis differencein reactionto competition? Thebehavior of men and womenin acompetitiveenvironment maydiffer becauseof differences in skill,talent, and beliefs.A competitiveenvironment may produce differences in behavioras subjectsadjust theirbest choices to different strategicenviron- ments.In particular, if subjectsbelieve (even if incorrectly)that menare more skillful at solvingmazes than women,and effortis 5.See Schuss [2001] and Solnick [1995] and for overviews Harwarth, Maline, andDeBra [1997]and the AAUW EducationalFoundation 1998 report “ Separated bySex: A CriticalLook at Single-SexEducation for Girls.” 1052 QUARTERLY JOURNALOF ECONOMICS costly,one would expectmales to put in moreeffort than females in thewinner-takes-all tournaments. Adifferent explanation is based onthe argument that pref- erencesover outcomes (that is,over individual effort,payment, and performance)are not independent of the institutional setup in whichthey are obtained and in particular ofthe competitive natureof the institution. The crucial element in this argumentis that male’s and female’s preferencesare affected differently by changesin theinstitution (its competitiveness,gender composi- tion,etc.). II. EXPERIMENTAL DESIGN We rstestablish an environmentin whichwe can measure theeffects of different incentiveschemes on performance.For this purposewe conduct experiments in whichparticipants haveto solvea realtask. 6 II.A. TheTask Participants weretold that thetask theyhave to perform is tosolve mazes. 7 Themaze game has velevels of difculty, from 1 5 easy to 5 5 hard. Each participant was askedto solve one mazeof dif culty level 2 in orderto get familiar with thetask. After eachparticipant nished onemaze, the nal part ofthe instructionswas distributed. Only this nal part differed between treatments. Thegame is solvedby operatingthe arrows on thekeyboard, trackinga markerthrough a mazeappearing onthe screen. Participants wereallowed touse only the arrows to move the cursor.The game was consideredsolved when the marker reachedthe end of the maze. The skill requiredto solve the problemrequires a moderateamount of familiarity with acom- puter,plus theability tolook forward in themaze to detectdead ends.After nishing amaze,participants wereasked to use the mousein orderto click “ OK”and “Newmaze,” and thenstart the newmaze using onlythe arrows. They were instructed not to use any otherfunction. After nishing amaze,they were asked to recordthis in atable.The experimenter