Authors: Katarzyna Grunt-Mejer, dr, Univerisity of Zielona Góra, Faculty of Education, Sociology and Health Sciences, Division of Rehabilitation and Psychology Jacek Grunt-Mejer, mgr, Warsaw University, Faculty of Psychology, Department of Cognitive Psychology Title: Not only a car: the relationship between the choice of transportation mode and road aggression Corresponding Author: Dr Katarzyna Anna Grunt-Mejer, k.gruntmejer@wpsnz.uz.zgora.pl Title: Not only a car: the relationship between the choice of transportation mode and road aggression Abstract: The study was to explore influence of choice of transportation means and locus of control on road aggression. Three phenomena are explored: active aggression (aggressive behavior on the road), driving anger (emotion caused by others' behavior) and risky driving. Risky driving is the lowest among people who alternate between public and private transportation. The latter also have the lowest level of active aggression, despite a high level of anger while driving. People alternating between a car and a bike display the lowest level of driving anger. Women express higher levels of anger while driving, while men are more prone to active aggression and risky driving. Locus of control is connected with anger while driving. Abstrakt: Celem badania była analiza wpływu wyboru środka transportu u umiejscowienia kontroli na agresję drogową w jej trzech wymiarach: agresję aktywną (wrogie zachowanie kierowane ku innym kierowcom), gniew podczas jazdy (emocja odczuwana w wyniku zachowań innych uczestników ruchu) oraz ryzykowną jazdę. Ostatnie zjawisko występuje najrzadziej u osób korzystających wymiennie z samochodu i komunikacji miejskiej. Ta grupa przejawia także najniższy poziom agresji aktywnej, lecz najwyższy gniewu podczas jazdy. Najniższy poziom gniewu podczas jazdy przejawiają kierowcy, które alternatywnie używają roweru. Kobiety mocniej odczuwają gniew podczas jazdy, a mężczyźni mają większe tendencje do aktywnej agresji i ryzykownej jazdy. Wewnętrzne umiejscowienie kontroli ma związek z niższym odczuwaniem agresji podczas jazdy. Keywords: Driving anger; road rage; transportation mode; risky driving; locus of control. Słowa kluczowe: gniew za kierownicą, furia drogowa, środek transportu, ryzykowna jazda, umiejscowienie kontroli Introduction Driving aggression is an increasing problem in most countries around the world (DePasquale, Geller, Clarke & Littleton, 2001; Parker, Lajunen & Summala, 2002). According to the Gallup Survey (2003) more than a half of drivers declared that they have been a victim of another person’s driving aggression during the year preceding the research. Although Poland was not included in this survey, data from the Polish government indicates that the situation here is worse: 80% of Polish drivers are exposed each week to some manifestations of aggression on the road (National Road Safety Council, 2004). Poland has one of the worst results in Europe in the terms of road safety (European Transport Safety Council, 2011) and driving aggression is largely responsible for that result (with experts considering aggression a cause of up to 23% of accidents (Goniewicz & Goniewicz, 2010). Therefore it is important to explore the factors that contribute to the intensity of the phenomenon and propose solutions to curb it. Definitions of road aggression Considering that terms related to road aggression are often overlapping, it is advisable to clarify the three most common definitions, often used interchangeably: aggressive or risky driving, road rage and anger while driving. Aggressive driving is a term describing reckless and dangerous behaviors such as speeding and other expressions of disrespect towards road traffic regulations. Numerous studies show increasing frequency of this phenomenon (e.g. Joint, 1995; Lex Report on Motoring, 1996; Mizell, 1997). Road rage is an extreme form of road aggression, connected with a physical attack on other road users, most frequently using a car or another dangerous object (Harding, Morgan, Indermaur, Ferrante & Blagg, 1998). Although the number of cases of road rage increases by a few percent each year (American Automobile Association, 1997), the phenomenon is still relatively rare. It also attracts media attention, which downplays the role of other forms of road aggression, which are much more dangerous in everyday life (Brewer, 2000; Lex Report on Motoring, 1996; Lawton, Parker, Stradling & Manstead, 1997; Parker, Lajunen & Stradling, 1998). According to this distinction the broad term road aggression should be used to describe all aggressive behavior on the road and it should not be used interchangeably with the term road rage (Ward, Waterman & Joint, 1998), which defines only the extreme expression of this phenomenon. More moderate symptoms of road aggression are easily observed in everyday life. The most often of them are honking, flashing lights, shouting at other drivers, tailgating and making obscene gestures (Joint, 1995; Naatanen & Summala, 1976; Parry, 1968; Shinar, 1998). The reason given most often by drivers for these behaviors is perceiving another driver’s speed as too slow or too fast (Lex Report on Motoring, 1996). Parker, Lajunen and Summala (2002) found that these as well as other behaviors considered to be frustrating (e.g. breaking the law, careless driving, staying in the left lane without intending to overtake) were annoying cross-culturally and caused the same kind of angry reactions. These behaviors are strictly interrelated and for this reason we labeled them together as active aggression. A term that is closely related to those mentioned earlier is anger while driving, an emotional state whilst driving a car, regardless of the results of the arousal. This means that anger while driving can, but does not necessarily, lead to behavioral expression of aggression. Deffenbacher, White and Lynch (2004) suggest that anger increases the possibility of risky behavior on the road, which in turn increases the risk of accidents. A state of anger also has a negative effect on perception, attention, information processing and reflexes, which may directly or indirectly be the cause of an accident. Individual and environmental factors of road aggression Among the individual factors potentially affecting the level of road aggression, the differences between men and women have been examined the most often. Despite that, the data does not allow firm conclusions to be drawn. Some research shows that the road situation creates an area of anonymity, in which women become as aggressive as men (Lightdale & Prentice, 1994) or even more so (e.g. Sullman, 2006; Brewer, 2000). However, most research supports the thesis that there is no difference between women and men in the general level of road aggression (Deffenbacher, Richards, Filetti & Lynch, 2005; Deffenbacher, Richards & Lynch, 2004). Sometimes the gender difference appears in terms of the way anger is expressed. For example, Lawton and Nutter (2002) proved that women often express their aggression in indirect ways by complaining or keeping the emotion bottled up rather than taking a harmful action. On the other hand, men are more predisposed to one of the direct forms of aggression or to more aggressive driving (which is also confirmed by the following studies: Esiyok, Yasak & Korkusuzt, 2007; Deffenbacher, Huff, Lynch, Oetting & Salvatore, 2000; Deffenbacher, Filetti, Lynch, Dahlen & Oetting, 2002; Deffenbacher, 2008; Arnett, Offer & Fine, 1997; Shinar & Compton, 2004). Small differences are also noticeable for stimuli that trigger anger in women and men: women experience more anger in the face of other’s law violations, while men express their anger more when police are present or another driver is driving slowly (Deffenbacher, Oetting & Lynch, 1994). Aggressive drivers are usually associated with young age and low driving experience. This statement is true for risky driving, however for other symptoms of road aggression research reveals the reverse to be true. Results of some studies point out that young drivers are more tolerant of stressful situations and respond with less aggression (Lajunen, Parker & Stradling, 1998; Sullman, 2006; Yasak & Esiyok, 2009). Some studies show no association between age, driving experience and the various manifestations of road aggression (Deffenbacher et al., 2000; Parkinson 2001). Road aggression was correlated with some psychological traits such as impulsive behavior; sensation seeking; conscientiousness; susceptibility to boredom (Dahlen, Martin, Ragan & Kuhlman, 2005; Schwebel, Severson, Ball & Rizzo, 2006); the Big Five features (Dahlen & White, 2006; Britt & Garrity, 2006); the tendency to forgive and thinking about future consequences (Moore & Dahlen, 2008); time perspective (Zimbardo, Keough & Boyd, 1997) and locus of control (Iversen & Rundmo, 2002; Gidron, Gal & Desevilya, 2003; Guastello & Guastello, 1986; Montag & Comrey, 1987). This last factor could influence the level of aggression in two ways. Firstly, individuals with a high level of internal locus of control are more willing to take responsibility for their own contribution to the difficult situation on the road, which should lead to a lower level of anger (Gidron, Gal & Desevilya, 2003). Secondly, individuals with a high level of internal locus of control could be more motivated to seek alternative possibilities for commuting, decreasing the risk of being dependent only on a car. Certain environmental factors such as traffic congestion, obstacles on the road, high temperature and the anonymity of drivers could be potential triggers for hostile behavior on the road (Shinar, 1998; Deffenbacher et al., 2005; Ellison-Potter, Bell & Deffenbacher, 2001; Potter, Govern, Petri & Figler, 1995; Kenrick & MacFarlane, 1986). Among them, traffic congestion has attracted the greatest attention of researchers. This factor has been repeatedly reported as a catalyst for road aggression as a result of environmental stress (Johnson, 1997; Shinar, 1998; Novaco, 1991). However, studies comparing conditions of high and low congestion lack coherent results: some of them report no significant difference in the level of road aggression (Lajunen, Parker & Summala, 1999; Deffenbacher, 2008), while others indicate that higher congestion leads to increased aggression (Underwood, Chapman, Wright & Crundall, 1999; Hennesy & Wiesenthal, 1997; Shinar & Compton, 2004). The current study In this study we have considered another situational factor, possibly contributing to increased road aggression, which is using a car as the only means of transportation. We assumed that a wide choice of transport modes can mitigate the level of stress related to commuting in two ways. Firstly, due to the existence of a choice depending on the circumstances and the lack of total dependence on a car when it is more advantageous to use another mode of transport (e.g. choice of a bike instead of a car in rush hours). Secondly, due to a greater level of empathy among car drivers, who also use public transport, bicycle or motorbike, especially in the situation when the possible obstruction is due to these means of transport. Other road users in this case would be not perceived as an inimical group, but rather as the same group, just temporarily in another situation. Some other factors related to road aggression were also included in the research, such as locus of control, driving experience, age, and gender. Internal locus of control has been found to be related to decreased anger while driving (e.g. Lajunen & Summala, 1995). Additionally, we assumed that individuals with internal locus of control would be prone to take control of their transportation mode choice, leading to conscious avoidance of potentially frustrating situations on the road. Driving experience, age and gender have been analyzed in an exploratory manner. The influence of the factors mentioned above was measured on three dimensions of road aggression: active aggression (easily observed behaviors, violent or rude, directed towards other road users), driving anger (emotion caused by others’ behavior, not necessarily openly expressed) and risky driving behavior. Two main hypotheses were assumed: 1. Road aggression in all three forms will be higher when individuals use only a car than when they use also alternative means of transport. 2. Road aggression in all three forms will be higher among individuals with a high level of external locus of control Additional analysis covering age, gender and experience were also conducted. Method Research participants 321 Polish license holders volunteered to take part in the study by completing an online questionnaire. The subjects were recruited by advertisements on internet forums related to automobile issues, whilst ensuring that women were not underrepresented. For this reason some specifically female forums were also chosen. In the end, of the 321 people who completed the survey, 205 were women (64%). The subjects’ age ranged from 18 to 74 yr (mean 27 yr). 13 subjects only finished primary school (4%), 144 had secondary education (44.9%) and 164 graduated from high school or had a university degree (51.1%). All subjects came either from large Polish cities where many possibilities of commuting are available or city outskirts where public transportation is also well developed. All subjects had driving experience and held a driving license. The largest group were people who commute only by car (42.5% - 136 people)(C). Next in line was the group using both a car and public transport (31.9% - 102 people)(CT), then people using a car, public transport or a bicycle interchangeably (11.3% - 36 people)(CTB) followed by a group using both a bicycle and a car (5.3% of the respondents - 17 people)(CB). The percentage of people commuting only by public transportation was 3.4% (11 people)(T). 7 people (2.2%) used a bicycle and public transport (BT) and the same number of people commuted only by car and motorcycle (CM). Two people (0.6% of respondents) used only bicycles (B) and the same number used a motorcycle, a bicycle and public transportation (MBT). As an indicator of experience, subjects were asked to estimate the number of kilometers driven. 129 people (40.6% of respondents) declared less than 10 thousand kilometers, 116 people (36.5% of respondents) said they had driven between 10 and 100 thousand kilometers and 73 people (23% of respondents) had driven more than 100,000 kilometers. Materials Three questionnaires were used. The shortened, 14 item version of the Driving Anger Scale (DAS; Deffenbacher et al., 1994; Deffenbacher et al., 2001) was translated to a Polish version. The Cronbach alpha coefficient for our sample was satisfactory (alpha = 0.807). The second questionnaire was created by authors according to the two different types of road aggression: active aggression and risky driving. This scale contained 14 items. After the PCA analysis with Equamax rotation we obtained four subscales of which two met the main criteria: each one was based on factors with an eigenvalue >1.5; each individual item was correlated with the factor concerned at the 0.45 level or above; only items with a communality of >0.50 were selected; the internal consistency of each subscale was >0.6. The first subscale referred to active aggression, defined as hostile behavior on the road (i.e. light flashing, making obscene gestures, honking the horn, making eye contact with another driver when angry, and starting an argument). Possible answers were: I never do it (1 point), I almost never do it (once a month or less) (2 points), I do it sometimes (several times a month) (3 points), I do it frequently (several times a week) (4 points), I always do it (several times a day) (5 points). Cronbach’s alpha coefficient for this subscale reached 0.71 (n=5). The second scale measured risky driving style. It contained the following questions: I often change lanes to overtake slower drivers, I respect speed limits (inverted), I try to rush other drivers by tailgating, I feel that people who overtake me drive too fast (inverted). Possible answers were: I never do it (1 point), I almost never do it (once a month or less) (2 points), I do it sometimes (several times a month) (3 points), I do it frequently (several times a week) (4 points), I do it always, when it is possible (5 points). Cronbach’s alpha coefficient for this subscale reached also 0,71 (n=4). To measure locus of control questionnaire "Delta" was used. This questionnaire was created by Drwal (1979) and is based on the Rotter theory (1966). The questionnaire contained 20 sentences stating a belief about one’s own control in life. A subject could agree or disagree with each of the sentences. A sample questions of scale is: My failures are the result of bad luck. Individual responses were aggregated using a key with the points. Furthermore, the questionnaire included eight questions to create lie scale (e.g. “I am never late”). Responses of people who received more than five points on the scale were not taken into account in the study. Results Choice of transport mode and road aggression To verify the first hypothesis subjects were divided into two groups: the first using only a car as a means of transport and the second, using a car and other forms alternatively. People who did not use a car at all were excluded from this calculation. As predicted, individuals commuting solely by a car revealed a greater level of risky driving than individuals using different means of transport (X =9,52, n = 136, SD = 2.86 and X = 8,79, n = 125, SD = 2,66, respectively, t(1, 259) = 2,13, p<.05). Post-hoc Tukey’s test showed that only the CT group was responsible for this differentiating result. Motorcyclists (CM) displayed the highest level of risky driving (in comparison with C, p=.09, with CT, p<.005, with CB, p=.17, with CTB, p<.05). Only CT was significantly less aggressive than C, p<.05. There was no difference between C and CB or CTB (p=.99 and p=.87 respectively). The difference between C and CT could be interpreted as a disproportionate amount of time spent on the road as a car driver, therefore not a real difference in propensity to road aggression, but rather in the opportunity to show it. For this reason an additional analysis was carried out, linking the average distance driven per year for both types of drivers with the frequency of risky driving. Although the C group had a greater average mileage (7604 km per year) than the CT group (6349 km per year), this difference was not significant, t(1,224) =1.05, p=0.29. There was also no significant correlation between the frequency of risky driving and the mileage for the CT group, r=.162, p=.12, but the correlation is significant for the C group: r=.34, p<.001. The second type of road aggression – active aggression - was the most common among drivers who were also motorcyclists or bicyclists, although these differences are significant only in comparison with CT (p=.059 and p<.05 respectively). Some differences between groups were shown in DAS results. The level of anger while driving was significantly lower for CB than CT (p<.005) and CM (p<.05). There was no statistical difference between other groups, although a tendency was visible between CT and C (p=.052), where C obtained a lower result. Women, who are more prone to anger while driving (see below) made up the majority of the CT group and this could explain the high results of anger while driving in the CT group. Because of this, ANOVA was conducted separately for both genders, revealing similar results, i.e. for men significant differences between CB and CT (p<.001), as well as between CT and C (p<.005) and for women between CB and CT (p<.001) and between CB and C (p<.005). Both genders have the lowest level of anger while driving in the CB group. Relationship between gender, means of transport and expression of aggression on the road. Since the use of means of transport is different for both genders, additional analysis was carried out: firstly to check the differences in all three phenomena related to driving aggression and secondly to see if there was a relationship between gender and aggression depending on means of transport. Chi square analysis showed that there was no difference in the number of men and women in the T (p=.55), C (p=.26) and CM groups (p=.70), but men were underrepresented in CT group (chi=12.02, p<.001) and women were underrepresented in CB group (chi = 7.44, p<.01). These results could be interpreted as a difference in the usage of a car, lower among women, for whom the average mileage per year reached 5772 km, while for men it was 9745 km (z(299) = 5.29, p<.0001). U MannWhitney’s test was conducted taking into account the difference in the number of men and women. In general, men obtained higher results for risky driving behavior (z(299)=4,22, p<.0001) and for active aggression (z(299)=3,50, p<.0001, but lower for anger while driving (z(299)=5.29, p<.0001). Women and men did not differ in any expression of road aggression when the CM, CMTB and CB groups were examined. Women tend to express more anger while driving than men in the C, CT and CTB groups (z(136)=2,53, p<.02, z(102)=3,30, p<.001, z(36)=2,25, p<.05, respectively). Men are more prone to risky driving behavior than women in the C group (z(136)=3.65, p<.001) and the CT group z(102)=3.29, p<.001). They are also more inclined to show active aggression in the C group, z(136)=3.39, p<.001). Relationship between road aggression and locus of control. Before exploration the relationship between aggression and locus of control, two effects were assumed: the choice of transport will be predicted by locus of control (internal locus leading to more independent choice of a transport mean, such as a bike) and locus of control will correlate with the level of aggression on the road in all three forms (the more external locus, the higher level of road aggression). To explore the first effect, discriminant analysis was conducted. Only car drivers were chosen for this analysis to preclude the effect of car accessibility. Locus of control was significantly related to an alternative choice of transportation mode, F(5,294)=2.45, p<.05, where the C group was compared with the rest. The specific results showed that the CBT and CB groups obtained the highest results in internal locus of control, followed by the C and CT groups, and the CM and CMBT groups displayed the lowest level of internal locus of control. The most significant differences occurred between following groups: CM and CB (p<.05), CM and CBT (p<.01), CBT and CT (p<.05), CBT and C (p<.05). Three choices seem to be important in these differences: using a bicycle (related to higher results in internal locus), using a motorcycle (related to a more external locus), using neither of them (moderate level of internal locus). The second assumption – correlation between locus of control and road aggression – was tested by regression analysis, with significant results obtained for anger while driving (F(1,296)=12.3, p<0.001, b0=43,92, b1=0,63). More internal locus of control resulted in a lower level of anger while driving. Risky driving and active aggression were not related to locus of control (p=.71 and p=.58, respectively) . Discussion The research revealed differences in the level of risky driving between car users and people who aside of a car also use public transportation. This result cannot be interpreted just in terms of lower frequency of car use in the CT group, since there is no relation between the amount of time spent behind the wheel and the level of risky driving in this group. However, this effect is observed for car users and could be related to the means of measurement, indicating how often during a week a subject engaged in an aggressive action. Considering this, it is possible then that people that use both a car and public transportation could have a lower tendency toward aggressive driving. There are two hypotheses to explain this effect: the CT group could not feel as self-confident behind the wheel as the C group, which leads them to use the services of professional drivers or they could have specific personality traits, including greater patience and being in less of a rush, leading to both using public transportation and safer driving. The results indicating that motorcyclists are the group with the greatest propensity toward risky driving is consistent with intuition. This group also reveals the greatest level of active aggression which are on a par with CB. Surprisingly high level of active aggression among cyclists could be related to very difficult conditions for bike riding in Polish cities and widespread failure to respect the rights of cyclists by car drivers (which occurs inter alia in the worst results in fatal accidents involving cyclists in the whole of Europe). For this reason cyclists may behave more aggressively, getting into arguments or shouting at others when they feel threatened or when they want their rights to be respected. DAS results indicate that the highest level of anger while driving is displayed by the CM and CT groups. Although the result for CM is not easy to interpret, it is consistent with two other expressions of road aggression and could lie at the root of them. The high level of anger while driving for the CT group could be interpreted in two ways. Firstly, despite major changes in this area in recent years, public transportation in Poland is still not sufficiently prioritized and independent from traffic. For example, one badly parked car on a tramline can block tram traffic for several hours without serious consequences for the car driver. Secondly, a high level of anger is common in the CT group, which leads to the choice of public transport in place of relying solely on a car. In other words, a person that tends to feel angry while driving may deliberately limit the amount of time spent behind the wheel. The research demonstrated that women have a greater tendency than men to feel driving anger. For both genders using a bicycle is associated with lower levels of anger while driving, which may be linked with avoiding many stressful situations on the road, very common for car drivers. Hostile and aggressive driving behaviors are more visible among men. Locus of control appeared to be associated with the choice of specific means of transport. Individuals with internal locus of control are more likely to use a bicycle, while a person with external locus of control are more apt to use a motorcycle. While both motorcycles and bicycles allow their users to avoid many situations in which car drivers would have problems (e.g. such as a lack of parking spaces), bicycles use is a choice that is more independent of road conditions (such as traffic jams, traffic management changes and repairs) and is the first choice for people who opt for full independence. A low level of internal locus of control, therefore the belief in fate and a lack of control over the life, may explain the reason motorcyclists choose a more dangerous means of transport. This could also be a reason for which the level of risky driving is the highest in this group. The hypothesis about the relationship between internal locus of control and road aggression was confirmed only for anger while driving, indicating that locus of control is more important for the explanation of a level of emotion on the road than for aggressive behavior. 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