psychology of popular media culture violent video games and

Psychology of Popular Media Culture

Violent Video Games and Real-World Violence: RhetoricVersus DataPatrick M. Markey, Charlotte N. Markey, and Juliana E. FrenchOnline First Publication, August 18, 2014. http://dx.doi.org/10.1037/ppm0000030

CITATIONMarkey, P. M., Markey, C. N., & French, J. E. (2014, August 18). Violent Video Games andReal-World Violence: Rhetoric Versus Data. Psychology of Popular Media Culture. Advanceonline publication. http://dx.doi.org/10.1037/ppm0000030

Violent Video Games and Real-World Violence:Rhetoric Versus Data

Patrick M. MarkeyVillanova University

Charlotte N. MarkeyRutgers University

Juliana E. FrenchVillanova University

Laboratory and correlational studies often find a link between violent video gamesand minor or benign forms of aggressive behaviors (e.g., exposing an opponent toan unpleasant noise). Based on these studies, the media, lawmakers, and researchersoften imply a link between violent video games and violent criminal behavior.Using a similar methodology employed by researchers to examine predictors ofsevere violent behaviors (Anderson et al., Journal of Personality and SocialPsychology 73: 1213–1223, 1997), 4 time-series analyses investigated the associ-ations among violent crime (homicides and aggravated assaults), video game sales,Internet keyword searches for violent video game guides, and the release dates ofpopular violent video games (both annually and monthly). Contrary to the claimsthat violent video games are linked to aggressive assaults and homicides, noevidence was found to suggest that this medium was positively related to real-worldviolence in the United States. Unexpectedly, many of the results were suggestive ofa decrease in violent crime in response to violent video games. Possible explana-tions for these unforeseen findings are discussed and researchers are cautionedabout generalizing the results from laboratory and correlational studies to severeforms of violent behavior.

Keywords: video games, time series, violence, homicide, ARIMA

Controlling the use of violent video games is one stepwe can take to help protect our society from vio-lence.—Brad Bushman (2013)

. . . high exposure to media violence is a major con-tributing cause of the high rate of violence in modernU.S. society.—Craig Anderson (2000), testimony be-fore the U.S. Senate Commerce Committee on theimpact of interactive violence on children.

There is considerable evidence relating vi-olent video games to aggressive behaviorsand cognitions. In a comprehensive meta-analysis, Anderson et al. (2010) identified 74

studies that used the “best practices” (i.e.,those studies that used valid measurementsand sound methodologies), and concludedthat exposure to violent video games is acausal risk factor for increased aggressivecognitions, aggressive affect, and aggressivebehaviors. Although some researchers havecautioned that the apparent negative effects ofviolent video games are small and may be aresult of publication bias (Ferguson, 2007),the popular media, lawmakers, and research-ers have often linked violent video games tosevere acts of violence. The current articleexamines whether the findings from thesestudies, which have been conducted primarilyin laboratories with college students, general-ize to severe forms of violent behavior occur-ring in the “real world.”

In the aftermath of the 1999 Columbine HighSchool shootings, many media outlets discussedviolent video games as one of the potentialcauses of this tragic event (cf., Simpson &

Patrick M. Markey, Department of Psychology,Villanova University; Charlotte N. Markey, Department ofPsychology, Rutgers University; and Julianan E. French,Department of Psychology, Villanova University.

Correspondence concerning this article should be ad-dressed to Patrick M. Markey, Department of Psychology,Villanova University, 800 Lancaster Avenue, Villanova, PA19085. E-mail: [email protected]

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Psychology of Popular Media Culture © 2014 American Psychological Association2014, Vol. 3, No. 2, 000 2160-4134/14/$12.00 DOI: 10.1037/ppm0000030

1

Blevins, 1999). Following the shootings at Vir-ginia Tech, local and national media noted thatthe gunman, Seung-Hui Cho, was a fan of theviolent video shooter game Counterstrike1 (cf.Benedetti, 2007). In a similar manner, mediasources reported that the Sandy Hook Elemen-tary School gunman, Adam Lanza, played thevideo game Call of Duty, a game that mimicswartime violence (cf., Smeltz, 2012).2 A searchof an online database of newspapers (ProQuestNewsStand) found that nearly 5,000 articleswere released in the aftermath of these threetragedies, which discussed video games in thecontext of these three school shootings. Theimplication in many of these articles was thatthese violent acts were precipitated and perhapseven caused by exposure to violent videogames. For example, on the popular ABC newsprogram 20/20, one TV commentator noted, “Inevery school shooting, we find that kids whopull the trigger are video gamers” (Thompson,2000).

The growing concern about a link betweenviolent video games and severe forms of violentbehavior prompted President Barack Obama in2013 to encourage scientists to research theeffects of violent video games (Molina, 2013).In the 30 years preceding this request, federaland local lawmakers conducted numerous hear-ings, proposed various legislative acts, andpassed approximately a dozen laws in an effortto regulate the sale of violent video games. Oneof the most salient political events concerningvideo games was the 1993 hearing on videogame violence led by Senator Joseph Lieber-man, resulting in the creation of the Entertain-ment Software Ratings Board (ESRB; Kent,2010). The ESRB is a self-regulatory organiza-tion whose purpose is to assign age and contentratings to video games. In 2011, the UnitedStates Supreme Court struck down a Californialaw prohibiting the sale of violent video gamesto youth, thereby affording video games thesame first-amendment protection as films, mu-sic, and other artistic works (Helle, 2011). Thisdecision by the Supreme Court has not curtailedthe concern of lawmakers. Following the trag-edy at Sandy Hook Elementary School, severallocal and federal bills were introduced, includ-ing the federal bill “Video Games EnforcementAct” (H.R. 287), which would regulate the saleof violent video games. Various legislators con-tinue to be concerned that violent video games

are a main contributor to youth violence, withSenator Lamar Alexander arguing that “ . . .video games is (sic) a bigger problem than guns,because video games affect people” (Linkins,2013).

In addition to lawmakers and the media, vi-olent video game researchers have linked thismedium to serious and deadly assaults. Thisconnection has been explicit at times, such aswhen researchers described violent video gamesas “murder simulators” (Grossman, 1998), orwhen arguing that video games can train chil-dren to kill in a manner similar to how a flightsimulator teaches a person to pilot a plane(Bushman, 2008; Gentile & Anderson, 2003).Some researchers have even contended that thenegative effect of violent video games on publichealth is similar to the causal relationship be-tween smoking and lung cancer (cf., Bushman& Anderson, 2001). Other times this link hasbeen more subtle, such as when researchersreference real-world violence to substantiate therationale of their research. For example, in thepeer-reviewed “best practices” studies identi-fied by Anderson et al. (2010), 28% of thestudies discussed severe forms of violence,most often within the introduction or abstract ofthe article.3 Of these studies, 42% presentedtheir research in the context of the ColumbineHigh School shooting, with the remaining dis-cussing other school shootings (e.g., the HeathHigh School shooting, Westside Middle Schoolshooting, etc.), homicide rates, and terrorism,including the September 11th attacks on theWorld Trade Center and the Pentagon. Outsideof journal pages, researchers have also linkedlaboratory findings with severe forms of vio-lence during interviews with the popular media.For example, in searching for possible motiva-tions of the 2013 Washington Navy Yard shoot-ings, one prominent researcher noted that “ . . .video game use may have been a contributing

1 A governmental panel created after the Virginia Techshootings found no evidence that Seung-Hui Cho everplayed or owned the game Counterstrike or any other vio-lent video game (Virginia Tech Review Panel, 2007).

2 A governmental report noted that although the shooterowned Call of Duty, he spent most of his time playingnonviolent games, including Dance-Dance Revolution andSuper Mario Brothers (Sedensky, 2013).

3 The first author of the current research article is also theauthor of one of the “best practices” studies that discussedviolent video games in the context of school shootings.

2 MARKEY, MARKEY, AND FRENCH

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factor,” and argued the shooter was probably amore accurate shot because he liked to play thevideo game Call of Duty (Bushman, 2013).

The concern about violent video games ex-pressed by the media, lawmakers, and research-ers may be justifiable, given the prevalence ofthis medium. Media researchers define a videogame as violent if a character in the game dis-plays realistic or cartoonish aggressive behaviortoward another character. This classification isnot focused on how graphic the violence is in agame; rather, it centers on whether the behaviorthe game character exhibits is intentionallyharmful to another game character (cf., Gentile,Saleem, & Anderson, 2007; Thompson &Haninger, 2001). This definition is consistentwith claims that cartoonish violence in E-ratedgames has the same negative effects on violentbehavior as realistic violence portrayed in M-rated games (Gentile et al., 2007). Conse-quently, regardless of a game’s ESRB rating,games that contain cartoonish and realistic vio-lence are both considered to be violent. Forexample, the violent video games used in thestudies identified as using the “best practices”(Anderson et al., 2010) included a cartoonishplatformer (Ty2; Rated E – content is suitablefor everyone), a violent first person shooter(Call of Duty; Rated M – content is suitable for17 years and up), an exaggerated version ofbaseball (MLB Slugfest; Rated E – content issuitable for everyone), and an adventure gamewhere the main character uses cartoonish at-tacks such as “pepper breath” (Herc’s Adven-ture: Rated E – content is suitable for every-one). According to this definition, the majorityof video games contain violence (Gentile, 2009;Thompson & Haninger, 2001; Thompson,Tepichin, & Haninger, 2006). In fact, among themost popular games sold in the past 5 years,more than 90% portray some form of violentbehavior.4

Realistic and cartoonish violent video gameshave been linked to aggressive behavior andcognitions in numerous correlational, experi-mental, and longitudinal studies (for reviewssee Anderson & Bushman, 2001; Anderson etal., 2010; Ferguson, 2007; Sherry, 2001). Thetypical correlational study in this area usesmainly questionnaires, asking participants tofirst describe their video game playing habitsand then self-report feelings or behaviors re-lated to aggression and violence. For example,

Anderson and Dill (2000) found that preferencefor violent video games was related to self-reported aggressive delinquency. The majorityof experimental studies involve having onegroup of participants play a violent video game(e.g., Grand Theft Auto, Call of Duty, etc.) andanother group play a nonviolent video game(e.g., Tetris, Top Spin Tennis, etc.) for a veryshort period (e.g., 15 minutes). Immediatelyafter playing the assigned video game, the ag-gressive cognitions or behaviors of the partici-pants are measured. Researchers using thismethodology have found that individuals whoplay violent video games are more likely toexpose others to “noise blasts” (a loud soundthat punishes others with an unpleasant noise;Anderson & Dill, 2000), report feeling morehostile on a questionnaire (Markey & Scherer,2009), and even give hot sauce to hypotheticalindividuals who do not like spicy food (Barlett,Branch, Rodenheffer, & Harris, 2009).

One limitation of previous research examin-ing violent video games and aggressive behav-ior is the manner in which “aggressive behav-ior” is operationalized. The majority of researchstudies in this area assess minor forms of ag-gression (e.g., giving an unpleasant noise or toomuch hot sauce to another person) or self-reports of aggressive feelings or behaviors. Aspointed out by others (Anderson, Bushman, &Groom, 1997), laboratory studies are somewhatlimited because how aggressive behavior ismeasured in these contexts is different fromsevere forms of aggression in the “real world,”which can involve aggravated assaults and ho-micides. In other words, is a person’s indicationthat they would give another person hot sauceanalogous to shooting another person?

Given the ethical problems associated withstudying real violence in a laboratory setting,researchers who study such severe forms ofviolence have often examined changes in vio-lent crime rates in relation to changes in avariable of interest across time. Consistent withthis notion, Anderson and colleagues havestressed the importance of examining changesin criminal data to determine whether these data

4 Represents the percent of game units sold between 2007and 2011, as reported by the sale tracking site vgchartz.com,which has an ESRB content descriptor for any type violence(e.g., intense violence, fantasy violence, cartoonish vio-lence, etc.).

3REAL-WORLD VIOLENCE

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point to the same conclusion as results fromother methodologies (e.g., laboratory studies;Anderson, 1987; Anderson et al., 1997). Be-cause each type of methodology affords differ-ent strengths and weaknesses, the confidence inthe validity of a finding is strengthened if di-verse methods support the same hypothesis.Conversely, if they do not support the samehypothesis, then the validity of the hypothesis iscalled into question.

To illustrate this notion, Anderson et al. (1997)presented a series of studies that examined the“heat hypothesis”—the idea that uncomfortablyhot temperatures increase aggressive behaviors.These researchers found that between the years1950 to 1995, the average annual temperatureswere positively related to aggravated assaults andhomicides, even after controlling for trends andserial dependency in the time series. What is per-haps most impressive about this study is, althoughviolent behavior has a multitude of causes, theeffect of heat was strong enough to express itselfin real forms of violent behavior. By linking tem-perature to the changes in violent behavior acrosstime, the authors of this study concluded that the“heat effect is real and significant when applied tolarge populations.” (Anderson et al., 1997, p.1222).

To determine whether violent video gameshave a “real and significant” effect when ap-plied to large populations, the current study alsoexamined changes in aggravated assaults andhomicides across time. Based on previous re-search and the speculation from the popularmedia, lawmakers, and researchers, it was pre-dicted that years or months where many indi-viduals were exposed to violent video gameswould yield relatively high rates of serious anddeadly assaults. To examine this prediction,four time-series analyses were conducted to in-vestigate the relations between various assess-ments of video game habits and violent crimewithin the United States. Analysis One exam-ined annual changes in video game sales andchanges in violent crime between 1978 and2011. Analysis Two investigated monthly videogames and monthly reports of aggravated as-saults and homicides between 2007 and 2011.Analysis Three examined how changes in Inter-net searches for video game walkthroughs andguides of popular violent video games wererelated to monthly changes in serious anddeadly assaults. Analysis Four investigated the

change in aggravated assault and homicide ratesfollowing the release of three extremely popularviolent video games. In each analysis, both con-current and delayed effects were examined. It ishoped that this comprehensive and diverse setof analyses will be able to detect any possiblelinks between violent video games and real-world violent behavior.

Analysis One: Annual Changes in VideoGame Sales and Violent Crime:

1978 to 2011

Although the video game industry began in1971, with the first commercially sold coin-operated video game Computer Space, it did notgain widespread attention until the release of theAtari 2,600 game console in 1977 (Goldberg &Vendel, 2012). Over the past 40 years, the videogame industry has grown to include hundreds ofcompanies, with worldwide sales expected togrow to $82 billion by 2017 (Gaudiosi, 2012). It isestimated that four of five homes in the UnitedStates with a male child have a video game sys-tem, with children playing video games an aver-age of 9 hr a week (13 hr for boys and 5 hr forgirls; Gentile, Lynch, Linder, & Walsh, 2004;Sherry, 2001). However, during this same period,violent crime has decreased. In 1978, the homi-cide rate in the United States was 9.0 homicidesper 100,000 people, but this rate dropped dramat-ically to 4.7 homicides per 100,000 people in 2011(United States Department of Justice, 2013).Given the prevalence of violence in most popularvideo games (Gentile, 2009; Thompson &Haninger, 2001; Thompson et al., 2006), the firstanalysis examined the link between overall videogame sales between 1978 and 2011 and changesin aggravated assaults and homicides.

Method

Data and sources.Annual video game sales. Annual game

sale data between 1978 and 2011 were providedby researchers at SuperData. SuperData is an in-dependent marketing company that collects datafrom publishers and developers to examine vari-ous trends within the video game market space(Van Dreunen, 2011). A second set of annualvideo game sales data were obtained from theNPD Group for the years 1997 to 2011 (data werenot available from this group prior to 1997). The


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NPD Group is a market research company thatcollects actual sales data from retailers and distrib-uters in addition to tracking consumer-reporterpurchasing behavior (NPD Group, 2013). Basedon these data, the NPD Group releases monthlyand annual reports to subscribers concerningvideo game sales. Both of these data sources pro-vided almost identical sales information fromoverlapping years (r � .92) and sales data wereaveraged for overlapping years. Annual sales fig-ures were then adjusted for inflation, and annualpopulation counts from the United States wereused to derive the amount of money spent onvideo game merchandise per 100,000 individuals(Figure 1).

Violent crime rates. The Federal Bureau ofInvestigation’s annual Uniform Crime Reports(UCRs) were used to compute annual aggravatedassault and homicide rates (United States Depart-ment of Justice, 2013). The UCRs contain crime-related statistics from most law enforcement agen-cies located in the United States, and consist ofmore than 17,000 city, county, state, and federallaw enforcement agencies who voluntarily submitdata concerning various crimes brought to theirattention. Aggravated assaults are defined as anunlawful attack on a person with the intent ofinflicting severe or aggravated bodily injury andoften involve the use of a weapon. Homicidecounts include the willful killing of another hu-man being and exclude deaths caused by negli-gence or accidents. For each violent crime, annualcrime rates per 100,000 were computed between1978 and 2011 (Figure 1).

Analytic Strategy and Results

All analyses were conducted using SPSS 21.Simple correlations revealed that annual videogame sales were negatively related to aggra-vated assault (r(32) � �.40, p � .05) andhomicide (r(32) � �.84, p � .01) rates. How-ever, these results need to be interpreted withextreme caution, as time series often contain aconsiderable amount of autocorrelation, indicat-ing that an observation for a given period iscorrelated with past periods (Sadler, Ethier,Gunn, Duong, & Woody, 2009; Warner, 1998).Autocorrelations and trends were removed fromeach time series using the Box–Jenkins ap-proach to fit time-series data to an autoregres-sive integrated moving average (ARIMA) sta-tistical model (Box, Jenkins, & Reinsel, 2008).

ARIMA models are a popular technique fordealing with time-series data and have beenused in numerous research studies across vari-ous disciplines. For each time series, anARIMA model is created by identifying auto-correlations and trends in the data. This modelis then used to estimate the parameters for agiven time series. By applying resultingARIMA models to each time series, a set ofresiduals for each series can be generated,which are free of trends, cycles, and autocorre-lations (a process called prewhitening; West &Hepworth, 1991).

The removal of trends is especially impor-tant; otherwise, a spurious relationship may befound between two time series simply becausethey share similar (or opposite) trends. For ex-ample, video game sales have tended to becomemore popular across these 36 years, whereascrime (especially homicide) has tended to de-crease during this period (Figure 1). Strongerevidence of the link between video game salesand violent crime would be provided if devia-tions from these trends were related to eachother. To examine this possibility, the residualsfrom each of the time series were related to eachother using the cross-correlation function(CCF). The CCF allows comparisons at thesame time point in both series (concurrent ef-fect) and up to a specific number of laggedperiods (see Warner, 1998 and West & Hep-worth, 1991, for additional information).

Based on autocorrelation and partial correla-tion functions, it was found that both annualreports of video game sales and aggravated as-sault were fit by an ARIMA (2,1,0) model, andan ARIMA (1,1,0) model was adequate to fitannual homicide rates (for additional informa-tion about ARIMA models, see Box et al.,2008). Ljung–Box Q tests for white-noise resid-uals revealed that when this model was appliedto video game sales (Ljung–Box Q at lag 10 �5.43, P � .86), aggravated assault rates (Ljung–Box Q at lag 10 � 7.86, P � .64), and homicide(Ljung–Box Q at lag 10 � 7.59, P � .70) rates,there were nonsignificant autocorrelationsamong the residuals. The ARIMA residuals forvideo game sales were then cross-correlatedwith the residuals for the crime assessmentsboth concurrently and up to a 4-year lag. Asseen in Figure 2, violent annual video gamesales were unrelated to concurrent rates of ag-


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Figure 1. Annual changes in video game sales and violent crime between 1978 and 2011.


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gravated assaults and homicides and remainedunrelated up to 4 years later.

Analysis Two: Monthly Changes in VideoGames and Violent Crime: 2007 to 2011

Results from the previous analysis revealedno link between changes in annual video gamesales and changes in serious and deadly assaultsacross 33 years. However, it is possible thatrather than affecting violent behavior yearslater, the negative effects of violent videogames are only expressed months later. Such apossibility is consistent with one large-scalemeta-analysis that found that, after controllingfor gender, violent video games have a smallbut significant concurrent effect on aggressivebehavior assessed in the laboratory (average r �.14), but this effect becomes much smaller whenexamined longitudinally (average r � .07; An-derson et al., 2010). To investigate the possibil-ity that the negative effects of violent videogames express themselves quickly, the secondanalysis examined monthly video game salesand monthly reports of aggravated assault andhomicide between 2007 and 2011.

Method

Data and sources.Monthly video game sales. Monthly video

game sales data were provided by the NPDGroup. For the current analyses, the NPD Groupprovided monthly sales data between January2007 and December 2011. Monthly sales wereadjusted for inflation, and yearly populationcounts were then used to derive the monthlyamount of money spent on video game mer-chandise per 100,000 individuals (Figure 3).

Monthly crime rates. The UCRs were usedto compute monthly aggravated assault and ho-micide rates between January 2007 and Decem-ber 2011 (Figure 3). Because the current anal-ysis focused on monthly reports of violent crimeonly, law enforcement agencies that consis-tently provided monthly crime statistics for agiven year were included in the analyses.


Simple correlations revealed that monthlyvideo game sales were negatively related toaggravated assault rates (r(58) � �.45, p �.01) and were unrelated to homicide rates

Figure 2. Cross-correlations between annual video game sales and violent crime. Note. Thehorizontal lines represent the 95% confidence interval under the null hypothesis.


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(r(58) � �.15, p � .25). However, as before,owing to the trends and dependency containedwithin these time series, these findings need tobe interpreted with caution. Because monthly

reports of video game sales and violent crimefollow a seasonal pattern (Figure 3), the sea-sonal ARIMA (SARIMA) extension was used(Box et al., 2008). SARIMA models are able to

Figure 3. Monthly changes in video game sales and violent crime between 2007 and 2011.


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deal with a time series that possesses a seasonalcomponent that repeats every s observations(e.g., every 12 months). The removal of sea-sonal trends is especially important if two timeseries share similar (or opposite) cycles. Forexample, video game sales peak during the win-ter (around December), whereas violent crimeincrease during the warm months (as predictedby the heat hypothesis; Anderson et al., 1997).Similar to the previous analysis, each time se-ries was prewhitened to remove trends, cycles,and autocorrelations. The residuals from thesetime series were then related to each other usingthe CCF both concurrently and up to 4 monthslater.

Using the autocorrelation and partial correla-tion functions, game sales could be fit with theseasonal model SARIMA (0,1,0)(0,1,1)12. Ag-gravated assault required two additional autore-gressive terms (SARIMA [2,1,0][0,1,1]12), andhomicide required four autoregressive terms(SARIMA [4,1,0][0,1,1]12) to achieve adequatefit and remove trends and cycles in the data (foradditional information about SARIMA models,see Box et al., 2008). Ljung–Box Q tests forwhite-noise residuals revealed that when thisseasonal model was applied to video game sales(Ljung–Box Q at lag 12 � 4.19, p � .98),

aggravated assault rates (Ljung–Box Q at lag12 � 6.95, p � .86), and homicide rates(Ljung–Box Q at lag 12 � 9.52, p � .66), therewere nonsignificant autocorrelations among theresiduals. The SARIMA residuals for videogame sales were then cross-correlated with theresiduals for the crime assessments both con-currently and up to a 4-mo lag. As seen inFigure 4, a negative relationship was found be-tween video game sales and concurrent rates ofaggravated assault (r � �.39). There were nosignificant lagged correlations, indicating thatmonthly video game sales were unrelated tomonthly rates of assaults and homicide up to 4months later.

Analysis Three: Keyword Searchers forViolent Video Games and Violent Crime:

2004 to 2011

Although the majority of video games con-tain some form of violence (Gentile, 2009;Thompson & Haninger, 2001; Thompson et al.,2006), Analysis Three examined the possibilitythat only extremely violent and realistic videogames affect serious forms of violent behavior.The current analysis focused solely on popularM-rated video games, which contain graphic

Figure 4. Cross-correlations between monthly video game sales and violent crime. Note.The horizontal lines represent the 95% confidence interval under the null hypothesis.


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and realistic forms of violence. Additionally,instead of examining the sales of video games,Analysis Three used a different assessment ofgame play.

One way to assess when individuals are play-ing a specific game is to examine behaviors thatare related to this activity. When playing videogames, players often use “walkthroughs” orstrategy guides to augment their play experi-ence. Before the popularity of the Internet, retailsales of the strategy guides for specific gamesfrequently sold more than 1 million copies(Snider, 2004). However, since the Internet hasbecome popular and widely accessible, a simplesearch using Google allows players to quicklyfind these guides online. Such walkthroughs andgame guides are available on various Web sites,one of the most popular being the CBS Interac-tive-owned “GameFaqs.” (Alexa, 2013). To es-timate when a large group of individuals areplaying violent video games, Analysis Threeexamined the Internet searches for walk-throughs and game guides for popular M-ratedviolent video games between 2004 and 2011.

The current analysis investigated Internetkeyword searches via the popular search engineGoogle. Using this service, a person might typethe words “walkthrough Grand Theft Auto” or“gamefaqs Grand Theft Auto” into Google’ssearch engine when attempting to find a walk-through or game guide to assist him or her withplaying this video game. For example, Figure 5displays the frequency of searches for the term

“walkthrough Grand Theft Auto” during thefirst year Grand Theft Auto IV was released. Aswould be expected, searches for this keywordphrase peaked in May following the release ofthe game on April 29, 2008. If playing the videogame Grand Theft Auto contributed to violentcrime, it seems likely a similar increase in crimewould have also occurred around May. Pastresearchers have successfully used Internet key-word searches to examine interest in a widevariety of topics, including seasonal affect dis-order (Yang, Huang, Peng, & Tsai, 2010), diet-ing (Markey & Markey, 2013), suicide (McCar-thy, 2010), pornography searches (Markey &Markey, 2010a, 2011), and even to track H1N1outbreaks (Ginsberg et al., 2009). In a similarmanner, Analysis Three examined whetherthere was a link among keyword searches forviolent video game walkthroughs and gameguides and concurrent and future rates of aggra-vated assault and homicide.

Method

Data and sources.Keyword searches for violent video game

walkthroughs and guides. Google Trendswas used to determine how often individualssearched for walkthroughs and game guides ofpopular violent video games between January2004 (the earliest time point data were avail-able) and December 2011. Violent video gamesearches included the keywords “walkthrough”

Figure 5. Internet keyword searches for Grand Theft Auto guides following the release ofthe Grand Theft Auto IV on April 29, 2008.


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or “gamefaqs” along with the name of popularM-rated violent video games sold within thisperiod (e.g., Call of Duty, Grand Theft Auto,Gears of War, Halo, etc.). For example, a userwho searched for “walkthrough of Halo” wouldbe included in this analysis, but a user who onlysearched for “Halo” or “walkthrough” would beexcluded. Google Trends examines Google Websearches to determine how many searches for thegiven set of keywords had been conducted in agiven week relative to the average number ofsearches on Google for those keywords over theentire observed period. Search data were stan-dardized by dividing the search volume for eachperiod by the greatest search volume and mul-tiplying by 100. In this range, a value of 100would indicate the period with the greatest over-all searches for a set of keywords. A period withhalf of the keyword searches as the highestperiod would receive a value of 50, and so forth(Google, 2013). Weekly reports were then ag-gregated to estimate the volume of Internetsearches for walkthroughs and game guides ofviolent video games that occurred each monthbetween January 2004 and December 2011(Figure 6).

Monthly crime rates. Violent crime statis-tics from the UCRs were used to computemonthly violent crime rates for aggravated as-sault and homicide. In the current analyses,monthly reports were collected between Janu-ary 2003 and December 2011 (Figure 6).


Searches for violent video game walk-throughs and guides were negatively related toaggravated assault (r(94) � �.31, p � .01) andwere unrelated to homicide (r(94) � �.12, p �.27). SARIMA models were used to prewhiteneach time series. Using autocorrelation and par-tial correlation functions, it was found that key-word searches for violent video game guidesand tips fit a SARIMA (1,0,0)(0,1,1)12 model,and both aggravated assault and homicide timeseries were fit by the same seasonal models usedin the previous analysis. Ljung–Box Q tests forwhite-noise residuals further revealed that whenthese models were applied to keyword searches(Ljung–Box Q at lag 12 � 9.49, p � .66),aggravated assault (Ljung–Box Q at lag 12 �10.00, p � .61), and homicide (Ljung–Box Q atlag 12 � 8.15, p � .83), it produced nonsignif-

icant autocorrelations among the residuals. Theresiduals of these time series were then relatedto each other using CCF concurrently and up to4 months later. As seen in Figure 7, keywordsearches for violent video game walkthroughsand guides were negatively related to both ag-gravated assaults (r � �.22) and homicides(r � �.22) 2 months later. None of the otherlags produced significant relations between key-word searches for violent video walkthroughsand guides, aggravated assaults, or homicides.

Analysis Four: Violent Crime Following theRelease of Three Popular Violent Video

Games

Video game releases are similar to movie re-leases in that the majority of the public consumesthe product when it is first released. The violentfirst person shooter, Call of Duty: Black Ops,earned $360 million the first day it was released,$650 million within the next 4 days, and morethan $1 billion in sales by 41 days (AssociatedPress, 2010). These impressive sales are not lim-ited to this single game. For example, between2003 and 2011, three of the most popular M-ratedviolent video games (Grand Theft Auto: San An-dreas, Grand Theft Auto IV, and Call of DutyBlack Ops) combined earned more than $3.5 bil-lion in sales. Given the violent content of thesegames and their popularity, the media, lawmakers,and researchers have linked Call of Duty andGrand Theft Auto to serious acts of violence in thereal world. Some have implied that Call of Dutywas a causal factor in numerous mass shootings,including the 2011 Norway attacks, the SandyHook Elementary School shooting in 2012, theToulouse and Montauban shootings in 2012, andthe Washington Navy Yard shootings in 2013(Bushman, 2013; Smeltz, 2012). Grand TheftAuto has been associated with both general trendsin violence and specific violent crimes, includingthe arrests of William and Josh Buckner in 2003for homicide; Devin Moore in 2003 for first-degree murder; Cody Posey in 2004 for homicide;Ryan Chinnery in 2008 for rape and grievousbodily harm; Stephen Attard, Samuel Philip, Dy-lan Laired, and Jaspreet Singh in 2008 for variousrobberies and assaults; and Zachary Burgess, only4 days after the release of Grand Theft Auto IV, in2013 for vehicle theft and kidnapping (cf., Crow-ely, 2008; Newcomb, 2013).


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If violent video games are causes of seriousviolent crimes, it seems probable that seriousand deadly assaults would increase followingthe release of these three popular violent video

games. To examine this hypothesis, the finalanalysis used an interrupted time-series analy-sis. Such a methodology has been used in thepast to examine numerous health and social

Figure 6. Monthly changes in searches for violent video game guides and violent crimebetween 2003 and 2011.


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issues and is among the strongest, quasi-experiment design available to evaluate longi-tudinal effects of “real world” outcomes (Wag-ner, Soumerai, Zhang, & Ross-Degnan, 2002).It is predicted that following the release of theseextremely popular violent video games, therewill be an increase in aggravated assaults andhomicides. Because the duration of this effect isunknown, increases in violent crime will beexamined for continuous periods of 1 to 12months after the release of these violent videogames.

Method

Data and sources.Release dates of popular violent video

games. The North American release dates ofGrand Theft Auto: San Andreas, Grand TheftAuto IV, and Call of Duty: Black Ops wereobtained from each game’s publisher (Figure 6).These three video games were selected becausethey were among the top-selling M-rated videogames during the period examined and owing totheir frequently discussed links with violentcriminal behavior (cf., Bushman, 2013; Crow-ely, 2008; Newcomb, 2013; Smeltz, 2012).

Monthly crime rates. UCR crime statisticsfrom the previous analysis were used to com-pute monthly violent crime rates for aggravatedassault and homicide between January 2003 andDecember 2011 (Figure 6).


Interrupted time-series analyses were com-puted to compare violent crime before and afterthe release of three popular violent videogames. In the current analysis, the violent crimerates following the release of Grand Theft Auto:San Andreas, Grand Theft Auto IV, and Call ofDuty: Black Ops were examined to determinewhether these games were related to changes inaggravated assaults and homicides. Specifically,monthly changes in violent crime were exam-ined for continuous periods of 1 to 12 monthsafter the release of these violent video games.This methodology provides insight into whetherthe release of these violent video games pre-dicted violent crime over and above the predic-tion derived from understanding the trends andcycles of violent crime, 1 to 12 months afterthese games were released.

Figure 7. Cross-correlations between searches for violent video game guides and violentcrime. Note. The horizontal lines represent the 95% confidence interval under the nullhypothesis.


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The same SARIMA models used in AnalysisThree were again used to eliminate trends, cy-cles, and autocorrelated errors in each time se-ries. Binary dummy variables were then used tomodel pulse effects on violent crime for contin-uous periods of 1 to 12 months after the releaseof these violent video games. Ljung–Box Qstatistics at a lag of 12 revealed nonsignificantautocorrelations among the residuals for each ofthe 24 analyses (12 for aggravated assault and12 for homicide). The resulting t tests for thepulse effects of each period were transformed tor-values to provide assessments of effect sizes.As can be seen in Figure 8, aggravated assaultrates tended to show a decrease following therelease of these three violent video games, butthis change failed to reach significance. Homi-cides also decreased after these violent videogames were released and displayed significantdecreases 3 and 4 months following the releaseof these games.

Discussion

Laboratory and correlational studies suggestviolent video games are a causal risk factor forincreased aggressive cognition, aggressive af-

fect, and aggressive behavior (Anderson &Bushman, 2001; Anderson et al., 2010; Fergu-son, 2007; Sherry, 2001). Based on the resultsfrom these studies, the media, lawmakers, andresearchers have linked violent video games toserious forms of violent behavior, including ag-gravated assaults and homicides. The currentstudy sought to examine whether such studies,which tend to examine mundane forms of ag-gression (e.g., giving an unpleasant noise or toomuch hot sauce to another person), generalize toserious and deadly assaults reported in the realworld. Crime data provided by the FBI for thepast 30 years along with sales of video games,Internet keyword searches for violent videogame guides, and release dates of popular vio-lent video games were examined annually andmonthly using large-scale time-series data ana-lytic techniques (e.g., ARIMA, SARIMA, inter-rupted time designs, CCFs, etc.). Concurrenteffects of violent video games and lagged ef-fects lasting months and years were considered.

Contrary to the claims that violent videogames are linked to aggressive assaults andhomicides, no evidence was found to suggestthat this medium was a major (or minor) con-tributing cause of violence in the United States.

Figure 8. Changes in aggravated assault and homicide rates following the release of threepopular violent video games. Note. The horizontal lines represent the 95% confidence intervalunder the null hypothesis.


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Annual trends in video game sales for the past33 years were unrelated to violent crime bothconcurrently and up to 4 years later. Unexpect-edly, monthly sales of video games were relatedto concurrent decreases in aggravated assaultsand were unrelated to homicides. Searches forviolent video game walkthroughs and guideswere also related to decreases in aggravatedassaults and homicides 2 months later. Finally,homicides tended to decrease in the monthsfollowing the release of popular M-rated violentvideo games.

The findings that violent crime was morelikely to show decreases instead of increases inresponse to violent video games were contraryto what was expected. One possible explanationfor this reduction in violence is that playingviolent video games leads to a catharsis. Inother words, when people play violent videogames, they are able to release their aggressionin the virtual world instead of in the real world.Consistent with this notion, adolescent boystend to report feeling less angry after playingviolent video games, and even actively select touse this medium to control their aggression (Ol-son, Kutner, & Warner, 2008). However, otherresearchers have found little evidence to suggestthat venting one’s anger on a safe target actuallyreduces aggression (cf. Bushman, 2002).

A more parsimonious and less contentiousexplanation than the catharsis effect focuses onthe qualities and desires of people who areinnately predisposed to violent behavior (cf.,Ferguson et al., 2008; Pinker, 2002). Individu-als who are prone to aggression and violencetend to seek out violent media, like videogames, to provide them with models that ex-press behaviors and desires consistent with theirown innate motivational system (Markey, inpress; Surette, 2012). When violent games, likeGrand Theft Auto or Call of Duty, are released,these aggressive individuals likely spend timeplaying these video games. Such a behavioreffectively removes these individuals from thestreets or other social venues where they mighthave otherwise committed a violent act. In otherwords, because violent individuals are playingviolent video games in their homes, there maybe a decrease in violent crime when popularviolent video games are released.

The results from this study should be consid-ered within the context of the methodologicallimitations of this study. Given both the number

of analyses conducted and the unexpected di-rection of the results in the current study, re-searchers should examine whether these resultsgeneralize to future periods and other geo-graphic regions. Additionally, although theoriesof video game violence operate at the level ofthe individual, data for the current study werecollected at the aggregate level. Owing to thisecological fallacy, caution is warranted whenattempting to draw causal relations betweenthese variables, as trends sometimes becomealtered when subpopulations are aggregated (i.e., Simpson’s paradox; Wagner, 1982). How-ever, even with this concern, prominent videogame researchers have argued that theoriesframed at the individual level can translate intoconcrete empirical predications at the aggregatelevel (Anderson et al., 1997). Consistent withthis notion, it was predicted that years ormonths when many individuals were exposed toviolent video games would yield relatively highserious and deadly assault rates. Such an empir-ical prediction is falsifiable, constituting “a le-gitimate test of the theory despite its cross-levelnature” (Anderson et al., 1997, p. 1221).

This research is also limited because it onlyexamined a single risk factor for violent behav-ior—violent video games. Researchers have of-ten adopted a risk factor approach when dis-cussing the negative effects of violent videogames. This approach acknowledges there aremany risk factors for violent crime. Each factormay elevate the risk for violent behavior, andwith enough risk factors present, it becomeslikely a person will act violently (Anderson,Gentile, & Buckley, 2007). No scientist hassuggested violent video games are the onlycause of violent behavior, just as no scientisthas suggested that heat is the only cause ofviolent crime or smoking is the only cause oflung cancer. Of course, risk factors like heat andsmoking are strong enough that when it be-comes hotter, there is a significant increase inviolent crime (Anderson et al., 1997), and asmore people have stopped smoking, there hasbeen a dramatic decrease in lung cancer rates(Centers for Disease Control and Prevention,2013). Such a pattern does not exist for violentvideo games. As more people have been ex-posed to violent video games, serious anddeadly assaults have not increased. It appearsthat any adverse effects violent video gameshave on serious violent behavior are either non-


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existent or they are dwarfed by the effects ofother factors that make the effects of violentvideo games appear nonexistent.

The rhetoric used by some in generalizing thefindings of research conducted primarily in lab-oratories and with questionnaires to serious anddeadly assaults appears to be unfounded. Thecurrent study found no evidence that violentvideo games are contributing to the high rate ofviolence in the United States (Anderson, 2000)or that controlling the use of violent videogames would protect our society from violentcrime (Bushman, 2013). The effect of violentvideo games on public safety does not appear tobe equivalent to the effect of smoking on lungcancer (Bushman & Anderson, 2001). Althoughvideo games might “affect people,” it is un-likely they are a bigger problem than guns(Linkins, 2013). If video games are really theequivalent of flight simulators training people tokill (Bushman, 2008; Gentile & Anderson,2003; Grossman, 1998), it is difficult to explainwhy homicide rates would go down after mil-lions of these “murder simulators” have beensold. When the media, politicians, or research-ers link the murderous rampages of male ado-lescents with violent video games, they are con-veying a classic illusory correlation (Ferguson,2013). These individuals are ignoring that 90%of young males play video games (Lenhart,2008). Finding that a young man who commit-ted a violent crime also played a popular videogame, such as Call of Duty, Halo, or GrandTheft Auto, is as pointless as pointing out thatthe criminal also wore socks. The rhetoric aboutviolent video games does not match the data.

It is important to note that in no way does thisconclusion imply previous research examiningviolent video games is unimportant. There isample evidence that violent video games doincrease aggressive cognition, aggressive affect,and some aggressive behaviors. It is possiblethat although violent video games are not re-lated to severe forms of violence, they mayaffect other types of less aggressive behaviors,such as bullying, spreading gossip, minor fightsat school, pushing and shoving, or hurling in-sults. This study also does not provide insightinto whether certain subpopulations are ad-versely affected by violent video games. Al-though research has been mixed on this issue(Ferguson & Olson, 2014), it is possible thatviolent video games adversely affect only some

individuals, and those who are affected havepreexisting dispositions (e.g., high levels ofpsychoticism, anger, etc.), which make themsusceptible to such violent media (Markey &Markey, 2010b; Markey & Scherer, 2009) Fi-nally, the current research does not address howexposure to violent video games at a young agemight affect later adult behavior. As scientists,we can reflect about such a relationship basedon available research, but we need to be upfrontthat this is only supposition. We need to be clearwith our peers and the general audience aboutthe claims we make that are backed up byresearch and those that are speculation. In short,as scientists, we need to be careful that we donot blur the line between our scientific resultsand our scientific conjecture.

References

Alexa. (2013). How popular is gamefaqs? Retrievedfrom http://www.alexa.com/siteinfo/gamefaqs.com

Anderson, C. A. (1987). Temperature and aggres-sion: Effects on quarterly, yearly, and city rates ofviolent and nonviolent crime. Journal of Person-ality and Social Psychology, 52, 1161–1173. doi:10.1037/0022-3514.52.6.1161

Anderson, C. (2000). Violent video games increaseaggression and violence: Senate Commerce Com-mittee hearing on the impact of interactive vio-lence on children. Retrieved from http://www.psychology.iastate.edu/faculty/caa/abstracts/2000-2004/00Senate.html

Anderson, C. A., & Bushman, B. J. (2001). Effects ofviolent video games on aggressive behavior, ag-gressive cognition, aggressive affect, physiologicalarousal, and prosocial behavior: A meta-analyticreview of the scientific literature. Psychological Sci-ence, 12, 353–359. doi:10.1111/1467-9280.00366

Anderson, C. A., Bushman, B. J., & Groom, R. W.(1997). Hot years and serious and deadly assault:Empirical tests of the heat hypothesis. Journal ofPersonality and Social Psychology, 73, 1213–1223. doi:10.1037/0022-3514.73.6.1213

Anderson, C. A., & Dill, K. E. (2000). Video gamesand aggressive thoughts, feelings, and behavior inthe laboratory and in life. Journal of Personalityand Social Psychology, 78, 772–790. doi:10.1037/0022-3514.78.4.772

Anderson, C. A., Gentile, D. A., & Buckley, K. E.(2007). Violent video game effects on children andadolescents. New York: Oxford University Press.doi:10.1093/acprof:oso/9780195309836.001.0001

Anderson, C. A., Shibuya, A., Ihori, N., Swing, E. L.,Bushman, B. J., Sakamoto, A., . . . Saleem, M.(2010). Violent video game effects on aggression,


Thi

sdo

cum

ent

isco

pyri

ghte

dby

the

Am

eric

anPs

ycho

logi

cal

Ass

ocia

tion

oron

eof

itsal

lied

publ

ishe

rs.

Thi

sar

ticle

isin

tend

edso

lely

for

the

pers

onal

use

ofth

ein

divi

dual

user

and

isno

tto

bedi

ssem

inat

edbr

oadl

y.

empathy, and prosocial behavior in eastern andwestern countries: A meta-analytic review. Psy-chological Bulletin, 136, 151–173. doi:10.1037/a0018251

Associated Press. (2010). Call of duty breaks salesrecord. Retrieved from http://www.cbc.ca/news/technology/call-of-duty-breaks-sales-record-1.949952

Barlett, C., Branch, O., Rodenheffer, C., & Harris, R.(2009). How long do the short-term violent videogame effects last? Aggressive Behavior, 35, 225–236. doi:10.1002/ab.20301

Benedetti, W. (2007). Were video games to blame formassacre? NBC News. Retrieved from http://www.nbcnews.com/id/18220228/#.UpNk9sQhijM

Box, G. E., Jenkins, G. M., & Reinsel, G. C. (2008).Time series analysis: Forecasting and control.Hoboken, NJ: Wiley. doi:10.1002/9781118619193

Bushman, B. J. (2002). Does venting anger feed orextinguish the flame? Catharsis, rumination, dis-traction, anger, and aggressive responding. Per-sonality and Social Psychology Bulletin, 28, 724–731. doi:10.1177/0146167202289002

Bushman, B. (2008). Grand theft summer vacation.Detroit Free Press. Retrieved from http://www.rcgd.isr.umich.edu/news/bushman.06.29.08.freep.pdf

Bushman, B. (2013). Do video games play a role inshootings? CNN.com. Retrieved from http://www.cnn.com/2013/09/18/opinion/bushman-video-games/

Bushman, B. J., & Anderson, C. A. (2001). Mediaviolence and the American public: Scientific factsversus media misinformation. American Psychol-ogist, 56, 477–489. doi:10.1037/0003-066X.56.6-7.477

Centers for Disease Control and Prevention. (2013).Lung cancer trends. Retrieved from http://www.cdc.gov/cancer/lung/statistics/trends.htm

Crowely, K. (2008). Video villains come to life. NewYork Post. Retrieved from http://nypost.com/2008/06/26/video-villains-come-to-life/

Ferguson, C. J. (2007). The good, the bad, and theugly: A meta-analytic review of positive and neg-ative effects of violent video games. PsychiatricQuarterly, 78, 309–316. doi:10.1007/s11126-007-9056-9

Ferguson, C. J. (2013). Don’t link video games withmass shootings. CNN.com. Retrieved from http://www.cnn.com/2013/09/20/opinion/ferguson-video-games/

Ferguson, C. J., & Olson, C. K. (2014). Video gameviolence use among “vulnerable” populations: Theimpact of violent games on delinquency and bul-lying among children with clinically elevated de-pression or attention deficit symptoms. Journal ofYouth and Adolescence, 43, 127–136. doi:10.1007/s10964-013-9986-5

Ferguson, C. J., Rueda, S. M., Ferguson, D. E., Fritz,S., & Smith, S. M. (2008). Violent video gamesand aggression: Causal relationship or byproductof family violence and intrinsic violence motiva-tion? Criminal Justice and Behavior, 35, 311–332.doi:10.1177/0093854807311719

Gaudiosi, J. (2012). New reports forecast globalvideo game industry will reach $82 billion by2017. Forbes. Retrieved from http://www.forbes.com/sites/johngaudiosi/2012/07/18/new-reports-forecasts-global-video-game-industry-will-reach-82-billion-by-2017/

Gentile, D. A. (2009). The rating systems for mediaproducts. In S. Calvert & B. J. Wilson (Eds.), Thehandbook of children, media, and development,(pp. 527–551), Hoboken, NJ: Wiley.

Gentile, D. A., & Anderson, C. A. (2003). Violentvideo games: The newest media violence hazard.In D. A. Gentile (Ed.), Media violence and chil-dren: A complete guide for parents and profession-als (pp. 131–152), West Port, CT: Praeger.

Gentile, D. A., Lynch, P. J., Linder, J. R., & Walsh,D. A. (2004). The effects of violent video gamehabits on adolescent aggressive attitudes and be-haviors. Journal of Adolescence, 27, 5–22. doi:10.1016/j.adolescence.2003.10.002

Gentile, D. A., Saleem, M., & Anderson, C. A.(2007). Public policy and the effects of mediaviolence on children. Social Issues and Policy Re-view, 1, 15–61. doi:10.1111/j.1751-2409.2007.00003.x

Ginsberg, J., Mohebbi, M. H., Patel, R. S., Brammer,L., Smolinski, M. S., & Brillian, L. (2009). De-tecting influenza epidemics using search enginequery data. Nature, 457, 1012–1014. doi:10.1038/nature07634

Goldberg, M., & Vendel, C. (2012). Atari Inc.: Busi-ness is Fun. Carmel, NY: Syzygy Company Press.

Google. (2013). Google trends. Retrieved fromhttps://support.google.com/trends/?hl�en

Grossman, D. (1998). Trained to kill. ChristianityToday. Retrieved from http://www.christianitytoday.com/ct/1998/august10/8t9030.html?order�&start�12

Helle, S. (2011). Back in the game. Chicago Tribune.Retrieved from http://articles.chicagotribune.com/2011-06-28/opinion/ct-oped-0629-video-20110628_1_games-and-aggressive-behavior-video-games-azeroth

Kent, S. (2010). The Ultimate History of VideoGames: From Pong to Pokemon and beyond. . .the story behind the craze that touched our livesand changed the world. New York, NY: RandomHouse Digital, Inc.

Lenhart, A. (2008). New Pew Internet/MacArthurreport on teens, video games and civics. Pew In-ternet and American Life Project. Retrieved fromhttp://www.pewinternet.org/Commentary/2008/


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September/New-Pew-InternetMacArthur-Report-on-Teens-Video-Games-and-Civics.aspx

Linkins, J. (2013). Lemar Alexander says videogames are ‘A bigger problem than guns’ but no,they aren’t. Huffingtonpost. Retrieved from http://www.huffingtonpost.com/2013/01/30/lamar-alexander-video-games-guns_n_2584837.html

Markey, P. M. (in press). Video games and mentalhealth. In H. Friedman (Ed.), Encylopedia of men-tal health. Elsevier Ltd., Oxford, UK.

Markey, P. M., & Markey, C. N. (2010a). Changes inpornography seeking behaviors following politicalelections: An examination of the Challenge Hy-pothesis. Evolution and Human Behavior, 31,442–446.

Markey, P. M., & Markey, C. N. (2010b). Vulnera-bility to violent video games: A review and inte-gration of personality research. Review of GeneralPsychology, 14, 82–91.

Markey, P. M., & Markey, C. N. (2011). Pornogra-phy seeking behaviors following midterm politicalelections in the United States: A replication of thechallenge hypothesis. Computers in Human Be-havior, 27, 1262–1264. doi:10.1016/j.chb.2011.01.007

Markey, P. M., & Markey, C. N. (2013). Annualvariation in Internet keyword searches: Linkingdieting interest to obesity and negative health out-comes. Journal of Health Psychology, 18, 875–886. doi:10.1177/1359105312445080

Markey, P. M., & Scherer, K. (2009). An examina-tion of psychoticism and motion capturecontrols asmoderators of the effects of violent video games.Computers in Human Behavior, 25, 407–411. doi:10.1016/j.chb.2008.10.001

McCarthy, M. J. (2010). Internet monitoring of sui-cide risk in the population. Journal of AffectiveDisorders, 122, 277–279. doi:10.1016/j.jad.2009.08.015

Molina, B. (2013). Obama seeks research into violentvideo games. USA Today. Retrieved from http://www.usatoday.com/story/tech/gaming/2013/01/16/obama-gun-violence-video-games/1839879/

Newcomb, A. (2013). Game over for man who al-legedly went on ‘Grand Theft Auto’ crime spree.ABC News. Retrieved from http://abcnews.go.com/blogs/headlines/2013/09/game-over-for-man-who-allegedly-went-on-grand-theft-auto-crime-spree/

NPD Group. (2013). About NPD. Retrieved fromhttps://www.npd.com/wps/portal/npd/us/home/

Olson, C. K., Kutner, L. A., & Warner, D. E. (2008).The role of violent video game content in adoles-cent development boys’ perspectives. Journal ofAdolescent Research, 23, 55–75. doi:10.1177/0743558407310713

Pinker, S. (2002). The blank slate: The modern denialof human nature. New York: Penguin.

Sadler, P., Ethier, N., Gunn, G. R., Duong, D., &Woody, E. (2009). Are we on the same wave-length? Interpersonal complementarity as sharedcyclical patterns during interactions. Journal ofPersonality and Social Psychology, 97, 1005–1020.

Sedensky, S. J., III (2013). Report of the State’s Attor-ney for the Judicial District of Danbury on the Shoot-ings at Sandy Hook Elemetary School and 36 Yoga-nada Street, Newtown, CT on December 14, 2012.Retrieved from http://cbsnewyork.files.wordpress.com/2013/11/sandy_hook_final_report.pdf

Sherry, J. L. (2001). The effects of violent videogames on aggression: A meta-analysis. HumanCommunication Research, 27, 409–431.

Simpson, K., & Blevins, J. (1999). Did Harris pre-view massacre on ‘Doom?’ Denver Post. Re-trieved from http://extras.denverpost.com/news/shot0504f.htm

Smeltz, A. (2012). Video games a flash point inConnecticut school rampage’s aftermath. Mc-Clatchy - Tribune Business News. Retrieved fromhttp://triblive.com/news/editorspicks/3203767-74/games-video-violent#axzz2lfYZVfnK

Snider, M. (2004, December 9). Strategy guides areas hot as video games. USA Today. Retrieved fromhttp://usatoday30.usatoday.com/life/books/news/2004-12-09-gaming-books_x.htm

Surette, R. (2012). Cause or catalyst: The interactionof real world and media crime models. AmericanJournal of Criminal Justice, 38, 1–18.

Thompson, J. (Speaker). (2000, March 23). ABCNews: 20/20. New York: American BroadcastingCompany.

Thompson, K. M., & Haninger, K. (2001). Violencein E-rated video games. Journal of the AmericanMedical Association, 286, 591–598. doi:10.1001/jama.286.5.591

Thompson, K. M., Tepichin, K., & Haninger, K.(2006). Content and ratings of mature-rated videogames. Archives of Pediatrics & Adolescent Med-icine, 160, 402–410. doi:10.1001/archpedi.160.4.402

United States Department of Justice. (2013). FederalBureau of Investigation: Uniform crime reportingprogram data: Offenses known and clearances byarrest, 1978–2011. Retrieved from http://www.icpsr.umich.edu/icpsrweb/NACJD/series/57/studies?archive�NACJD&q�county-level&paging.rows�25&sortBy�7

Van Dreunen, J. (2011). A business history of videogames: Revenue models from 1980 to today. Pre-sented at the Game Behind the Video Game: Busi-ness, Regulations, and Society in the Gaming In-dustry Conference, New Brunswick, NJ.

Virginia Tech Review Panel. (2007). Mass shootings atVirginia Tech. Retrieved from http://www.governor.virginia.gov/TempContent/techPanelReport.cfm


Thi

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dby

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anPs

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logi

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ocia

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oron

eof

itsal

lied

publ

ishe

rs.

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tend

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Wagner, A. K., Soumerai, S. B., Zhang, F., & Ross-Degnan, D. (2002). Segmented regression analysisof interrupted time series studies in medication useresearch. Journal of Clinical Pharmacy and Ther-apeutics, 27, 299–309. doi:10.1046/j.1365-2710.2002.00430.x

Wagner, C. H. (1982). Simpson’s paradox in real life.American Statistician, 36, 46–48.

Warner, R. M. (1998). Spectral analysis of time-series data. New York, NY: Guilford Press.

West, S. G., & Hepworth, J. T. (1991). Statisticalissues in the study of temporal data: Daily experi-

ences. Journal of Personality, 59, 609–662. doi:10.1111/j.1467-6494.1991.tb00261.x

Yang, A. C., Huang, N. E., Peng, C. K., & Tsai, S. J.(2010). Do seasons have an influence on the inci-dence of depression? The use of an internet searchengine query data as a proxy of human affect.PLoS ONE, 5, e13728. doi:10.1371/journal.pone.0013728

Received November 26, 2013Revision received January 31, 2014

Accepted February 3, 2014 �


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