The Journal of Social Psychology, 155: 12–29, 2015 Copyright © Taylor & Francis Group, LLC ISSN: 0022-4545 print / 1940-1183 online DOI: 10.1080/00224545.2014.959884

The Campbell Paradigm as a Conceptual Alternative to the Expectation of Hypocrisy in Contemporary Attitude Research FLORIAN G. KAISER Otto-von-Guericke University

KATARZYNA BYRKA University of Social Sciences and Humanities

ABSTRACT. Hypocrisy—professing a general attitude without implementing corresponding attitude-relevant behavior—is, according to Ajzen and Fishbein (2005), commonly found in attitude research that aims to explain individual behavior. We conducted two studies that adopted the Campbell paradigm, an alternative to the traditional understanding of attitudes. In a laboratory experiment, we found that specific attitude-relevant cooperation in a social dilemma was a function of people’s pre-existing general environmental attitude. In a quasi-experiment, we corroborated the reverse as well; engagement in attitude-relevant dietary practices was indicative of environmental attitude. When using Campbellian attitude measures, there is no room for hypocrisy: People put their general attitudes into specific attitude-relevant practices, and differences in people’s general attitudes can be derived from their attitude-relevant behavior. Keywords: attitude-behavior consistency, attitudes, conservation (ecological behavior), environmental attitudes, social dilemmas

LAYPERSONS COMMONLY EXPECT THAT ENVIRONMENTALISTS are more likely to refrain from using cars than nonenvironmentalists, and that members of environmental organizations in contrast to nonmembers are more likely to act pro-environmentally in general. However, such consistency expectations regarding an empirical relation between a person’s general environmental attitude and his or her specific pro-environmental behavioral conduct are at odds with one of the dominant traditions in contemporary attitude research. According to Ajzen and Fishbein (2005), rather than consistency between general attitudes and specific behavior, one should typically expect hypocrisy:1 this is the practice of professing a certain general attitude (e.g., favoring environmental protection to a certain extent) without implementing corresponding behaviors (e.g., reusing shopping bags). Typically, it has been found that hypocrites (i.e., attitudeinconsistent actors) do not differ from attitude-consistent actors in their general attitudes (see Address correspondence to Florian G. Kaiser, Otto-von-Guericke University, Institute of Psychology, P.O. Box 4120, D-39016 Magdeburg, Germany. E-mail: [email protected]; or to Katarzyna Byrka, University of Social Sciences and Humanities, Social Psychology Department, Ostrowskiego 30b, 53-238 Wroclaw, Poland. E-mail: [email protected]

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Ajzen, Brown, & Carvajal, 2004; Sheeran, 2002). Hypocrisy—the apparent behavior-irrelevance of verbal expressions of general attitude—is also challenging for applied social psychology, which usually describes behavior as a function of attitudes (e.g., Fishbein et al., 2001).2 In this article, we argue that the hypocrisy standard is eliminated if we revisit the contemporary view of what attitudes are. Most conceptual notions in social psychology are governed by the idea that attitudes represent unobservable, latent properties that are manifested when a person professes more or less appreciation for an attitude object (e.g., Eagly & Chaiken, 1993). These unobservable properties are in turn expected to causally and deterministically control behavior (see e.g., Milfont & Duckitt, 2004), as with the claim, for example, that an attitude must be activated before it can bring about a certain behavior (cf. Fazio, Sanbonmatsu, Powell, & Kardes, 2008). As a seemingly causal effect of behavior on attitude as measured with evaluative statements has also been acknowledged, people’s perceptions of their own activities have been taken to feed into the formation of their attitudes (e.g., Bem, 1967). Thus, portraying the attitude-behavior relation as a causal one has traditionally led to scientific debates not only about hypocrisy but also about the causal direction of the relation. An alternative conception of attitudes was captured in the 1960s by DeFleur and Westie (1963; see also Campbell, 1963). They described attitudes as inferred properties that can be “. . . equated with the probability of recurrence of behavior forms of a given type or direction” (p. 21). Such an understanding portrays attitude and behavior as indivisible in that it renders the attitude-behavior relation to be a formal rather than causal one (see also Greve, 2001). This latter notion remained dormant in attitude research until recently. Kaiser, Byrka, and Hartig (2010) adopted DeFleur and Westie’s (1963) definition of attitudes and developed what they call the Campbell paradigm. Before we turn to the specific hypotheses of this research, we will describe the Campbell paradigm, which we understand will be unfamiliar to many readers.

The Campbell Paradigm Donald Campbell (1963) had originally proposed a transitive item structure as the measurement model for individual attitudes. According to Campbell’s proposal, a person’s esteem for an attitudinal object (e.g., environmental protection) or goal (e.g., protecting the environment) becomes increasingly obvious in the face of increasing difficulties, such as painful sacrifices that come with an action. Thus, for example, if a person aspires to protect the environment, then he or she can be expected to engage in a set of activities that reflect his or her attitude. The person may publicly express the importance of energy conservation, may recycle cardboard regularly, may claim to refrain from using cars, and may engage in a variety of other activities relevant to that goal. The more obstacles or difficulties a person overcomes and the more effort that person expends toward implementing the particular goal, the stronger that person’s commitment to the goal and, thus, the stronger the person’s attitude. Why would someone recycle glass and commute by bike in inclement weather and endure lower temperatures at home and give money to environmental organizations if he or she was not dedicated to environmental protection? Conversely, when the slightest inconvenience is enough to stop a person from taking the appropriate behavioral steps, his or her environmental attitude is probably rather weak. Campbell (1963) proposed using the deterministic Guttman model (see Guttman, 1944) to implement his measurement idea for individual attitudes. Kaiser and colleagues (2010) viewed

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this proposal as unrealistically stringent, and as an alternative, they proposed using the probabilistic Rasch model (see Rasch, 1960/1980). For their formulation of the Campbell paradigm, establishing a transitive structure of the behavioral indicators of an attitude thus becomes essential. However, it is not essential that the behavior from which the attitude is inferred is exclusively comprised of observed overt acts; verbal acts—that is, self-reports of behavioral engagement or conventional attitude items (i.e., expressions of appreciation toward an attitude object, such as environmental protection or pro-environmental behavior)—will suffice as well. Expectedly, Byrka and Kaiser (2013) confirmed that traditional attitude items in the form of verbal expressions of appreciation for behaviors, together with straightforward self-reports of such behaviors, represent a single category of indicators of verbal behavior, as they represent a transitively ordered class (see also Brügger, Kaiser, & Roczen, 2011). A similar conclusion based on a related measurement model can be found in Andrich and Styles (1998). In other words, a successful Rasch model test corroborates that the behavioral indicators from which the attitude is inferred fall on a single dimension and thus represent a transitively ordered class of indicators. So far, Kaiser and colleagues have successfully performed such Rasch model tests with various sets of behavioral self-reports (see e.g., Kaiser, 1998; Kaiser, Oerke, & Bogner, 2007; Kaiser & Wilson, 2000, 2004). Within the Campbell paradigm, referring to the general attitude in order to explain the specific self-reports of behavior from which the general attitude is derived would be circular and thus conceptually trivial (Greve, 2001: also Campbell, 1963; DeFleur & Westie, 1963). It would not be circular, however, if a general attitude—and here we are interested in environmental attitude— as derived from self-reports of a large range of pro-environmental behaviors was predictive of a single, overt pro-environmental behavior that was not included in the original assessment of the general attitude (Study 1). Conversely, it would not be trivial if a specific attitude-relevant selfreport that was not included in the original assessment of the general attitude was found to account for systematic differences in people’s general environmental attitude (Study 2). Note that these two expectations are in contrast to findings from traditional attitude research (see e.g., Ajzen et al., 2004) that employed the usual approaches to the measurement of individual attitudes (see e.g., Eagly & Chaiken, 1993).

Research Goals The objective of this research was to assess two nontrivial empirical claims reflecting the conceptualization of an attitude as a property that can be inferred from individuals’ behavioral self-reports. Our research extends the available evidence regarding the Campbell paradigm in two new directions. In Study 1, we experimentally tested our prediction that the extent to which a person holds a general attitude (i.e., environmental attitude) would explain the occurrence of an overt, specific, attitude-relevant pro-environmental behavior (i.e., energy consumption in a commons dilemma), provided that the attitude measure represents a Rasch scale and, thus, a Campbellian measure of general attitude. In Study 2, we predicted the converse: We anticipated that differences in expressions of engagement or nonengagement in a specific behavior with objectively demonstrable attitude-relevance (i.e., avoiding the consumption of meat and other animal products) would correspond with individuals’ general environmental attitude but only when general attitude was assessed with a Campbellian attitude measure.

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STUDY 1 Social dilemmas are public-good or resource dilemmas that stem from open access to a resource (see e.g., Komorita & Parks, 1995). In such situations, people are confronted with what is assumed to be a conflict between their personal self-interest and the greater collective interest. More often than not, people do not cooperate for collective benefit but rather exploit resources to their personal advantage. The pursuit of self-interest is the dominant strategy in such dilemmas, and, thus, cooperation with others is the relatively more demanding behavioral choice (Gifford & Hine, 1997). Many contemporary environmental problems can be conceptualized as social dilemmas as illustrated by Garrett Hardin (1968) in his seminal article “The Tragedy of the Commons.” Surprisingly, environmental attitude (which is traditionally measured on the basis of expressions of appreciation), to our knowledge, has never been found to promote cooperation in simulated social dilemmas (see, e.g., Smith & Bell, 1992). Although people have been found to differ in their inclination to cooperate with one another in social dilemmas (Kramer, McClintock, & Messick, 1986), this inclination is almost exclusively linked with people’s prosocial orientation and their thoughts about others (Gifford & Hine, 1997; Kollock, 1998; Komorita & Parks, 1995; Weber, Kopelman, & Messick, 2004). It is grounded either in social conformity, altruistic values, and moral principles, such as equality or equity (van Dijk & Wilke, 1995), in a person’s individual expectations of others’ behaviors (Ledyard, 1995), or in a person’s social value orientation (van Lange, 1999). For the last item, prosocials are thought to be dispositionally inclined to cooperate with others (Brucks & van Lange, 2007). Expectedly, a prosocial disposition, reciprocity, and other justice or fairness considerations have been proposed to be at the core of people’s inclination to cooperate in social dilemmas (Kollock, 1998; Weber et al., 2004). Accordingly, cooperation with others at its best means dividing the common resource into equal parts and extracting one’s fair share at a rate that allows replenishment (i.e., avoids depletion and guarantees sustained use; Gifford & Hine, 1997). Thus, we should not expect less but also not more cooperation in social dilemmas even from individuals who aspire to maintain a fair balance between the interests of others and their own self-interests. Due to self-interest, it would be irrational to restrain oneself more than necessary from using the common resource beyond what guarantees the sustained use of the resource. However, “die-hard” environmentalists hold a different perspective. Extreme environmentalists view environmental protection as an absolute. Thus, for such persons with comparatively high environmental attitudes, self-sacrifices can be expected—even beyond limiting oneself to one’s fair share (Gifford & Hine, 1997; Hardin, 1968). In Study 1, we predicted that the extent of a person’s environmental attitude would determine cooperation in a social dilemma if cooperation was related to an attitude-relevant specific behavior such as energy consumption. To our knowledge, no such effect has ever been demonstrated before. In addition, we controlled for a person’s social value orientation, the one person property that, to date, best explains the variance in cooperation in social dilemmas (Gifford & Hine, 1997). Originally, we had suspected that the link between energy consumption and its environmental relevance might not be immediately obvious to all our participants. Thus, as a precautionary measure, we explicitly stressed the environmental relevance of energy consumption to some of our participants. This is why we included a second hypothesis: Cooperation will follow only if the attitude relevance of energy consumption is made salient.

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METHOD Participants The selection of the participants was based on their level of environmental attitude measured 2 years previously. We re-contacted 502 persons from the original convenience sample of 1,746 residents of Eindhoven, The Netherlands, first by mail and subsequently by telephone. Persons with relatively high levels of environmental attitude had scores at least 1 SD above (i.e., at 0.59 logits3 and over) the average attitude score (M = –0.17 logits). Low environmental attitude was defined as an average score or lower. The quantitative distinction between persons high and low in environmental attitude was, thus, minimally 1 SD (i.e., ≥ 0.76 logits). Of the 502 persons contacted, 344 (68.5%) were considered low and 158 (31.5%) high in their environmental attitudes. Sixty-eight (13.5%) persons could not be reached, and 259 (51.6%) refused to come to the laboratory. Of the 175 (34.9%) persons who agreed, 131 (26.1%) persons with a mean age of 54.9 actually came to the laboratory: 57 (43.5%) high and 74 (56.5%) low in environmental attitude; 79 (60.3%) men and 52 (39.7%) women. Experimental Setup For the social dilemma game in which the participants’ aim was to collect as much of the resource as possible, we deliberately selected a common variant, played in 10 rounds, in which the resource was replenishable (cf. Hine & Gifford, 1991). Each round ended with a participant’s choice to remove a certain amount of the resource (either kiloWatt [kWatt] or points) followed by randomly generated feedback telling the participant whether the demanded amount was granted or not. The dependent variable was the number of units requested from the maximally available resource (i.e., 10 kWatt or points). Each person was allowed to maximally demand 50% of the resource (i.e., 5 kWatt or points). Experimental conditions. In addition to a person’s level of environmental attitude, two other between-subjects factors were included. First, the environmental relevance of energy consumption either was or was not explicitly made salient. Half of the participants received a video message that explicitly connected energy consumption with environmental risks and pollution such as weather-related disasters and oil spills. The other half did not receive such a message; for them, the connection was left implicit. Second, the social dilemma game was presented in either an attitude-relevant or -irrelevant format. In the environmental attitude-relevant format (i.e., the energy consumption condition), the resource was presented as a shared power generator producing energy on a pristine island, and energy was presented as a means for accessing commodities (e.g., the cooling of air or beverages). In the environmental attitude-irrelevant condition, the game was presented as a game for points, and the resource was presented as a pool of credit points. The available resource in each round was fixed at 10 units of either kWatt or points. Pay-off function. For our experiment, a pay-off function had to be determined; we adopted the one proposed by Suleiman and Budescu (1999) with the exception that our resource was fixed at 10 units (instead of being variable). The individual pay-off was determined by using the

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available resource as the benchmark. If the demand exceeded 10 units, no credits were received. If the total demand was 10 or fewer units, the requested amounts were granted. Procedures The participants were invited to the laboratory in groups of four to eight individuals to take part in a study about decision-making. They were welcomed by an experimenter and seated in separate cubicles equipped with personal computers. Subsequently, the instructions were presented on the computer screen. The participants learned that they would engage in a group task together with four other persons connected via the Internet. In fact, they were not connected to the Internet, and the other participants were simulated. Participants were asked to generate nicknames. These nicknames then appeared on the screen together with two other nicknames, allegedly representing contenders. While waiting for two more imaginary contenders to log in, participants were asked to fill out the social value orientation measure. When completed, participants were informed that the remaining contenders had, in the meantime, logged in, and that the experiment was about to begin. Except for the environmental attitude condition, participants were randomly assigned to the experimental conditions. After completing the social dilemma game, the participants were asked to report their environmental attitude a second time along with some questions asking for socio-demographics. Participants were offered C 6.50 for their time and effort. One month after the experiment, participants who had consented to our offer were informed about the purpose and the results of our research. Measures The average demand of the resource in each of the 10 experimental trials was our dependent variable. Note that cooperation with others can be defined accordingly as 2 kWatt or points because two units represent a person’s fair share in a five-person game consisting of 10 units. Environmental attitude was measured in the Campbellian sense as a Rasch scale (see Kaiser et al., 2010). For that, we had originally used 50 self-reported pro-environmental behaviors adopted from the General Ecological Behavior (GEB) scale (Kaiser & Wilson, 2004). Typical examples of items are “I reuse my shopping bags” and “I am a member of an environmental organization.” In order to avoid bothering participants with a large number of identical questions in the second assessment 24 months after their first assessment, 20 behavioral self-reports were randomly selected for each individual from the original 50 behavior items. Whereas persons with an originally high environmental attitude were not given extremely easy items, persons originally low in their environmental attitude were not given extremely difficult items. Such a procedure is feasible due to the technical features of the Rasch model (i.e., uniform item discrimination). Operational Rasch scales entail that the indicator items (in our case, self-reports of behavior) from which a person property (in our case, general environmental attitude) is inferred represent a single—for all persons—transitively ordered class of items. Also, the inferred property must be sufficient for accurately anticipating the responses of the persons. Successful Rasch model tests are thus true empirical tests that can fail (see, e.g., Bond & Fox, 2007). The extent of a person’s attitude was determined on the basis of a maximum likelihood approach, which is the conventional way to score people with Rasch scales (see, e.g., Embretson & Reise, 2000). Environmental attitude had a reliability of rel = .70 (N = 131), which

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corresponded with the first assessment 2 years earlier (rel = .71). Moreover, our assessment of people’s environmental attitude was highly consistent despite a time lag of about 24 months: r = .67; rcorr = .96 when corrected for measurement error attenuation (for calculation details, see Charles, 2005). Social value orientation was measured with nine questions developed by van Lange, de Bruin, Otten, and Joireman (1997). Each of these nine questions has three response alternatives. Typically, a person is asked to grant points to another person and to himself or herself according to personal preference. One of the options represents a prosocial choice (e.g., 500 points for oneself, and 500 points for the other), one an individualistic choice (e.g., 500 points for oneself, and 400 points for the other), and one a competitive choice (e.g., 400 points for oneself, and 100 points for the other). A particular value orientation is assigned when a person prefers the same type of choice at least six out of nine times. Of the 131 participants, 113 (86.3%) were classifiable. When using this measure, it is common to find that a certain percentage of participants will answer the nine questions inconsistently and thus cannot be classified reliably. These unclassifiable persons were excluded from the statistical analyses that involved the social value orientation measure. The vast majority of our participants were prosocials (n = 86; 65.7%), with only 27 (20.6%) proselfs (i.e., 18 [13.7%] individualists and 9 [6.9%] competitors).

RESULTS With our 2 × 2 × 2 factorial design [environmental attitude (high/low), salience of environmental relevance (explicit/implicit), environmental-attitude-relevance of experimental setup (energy/points)], we conducted two planned orthogonal contrasts to test our hypotheses (an approach recommended by Maxwell & Delaney, 2004). In the first contrast, we compared participants high in environmental attitude in the attitude-relevant energy-consumption condition who had been made aware of the environmental relevance of energy (i.e., explicit salience: n = 14) with the ones who had not been made aware of it (i.e., implicit salience: n = 14). Note that the test used the total sample’s pooled variance, which provided more degrees of freedom than a conventional t-test and thus had more power. The salience of the link between energy consumption and its environmental relevance did not significantly affect the energy demanded by participants high in environmental attitude in the attitude-relevant energy-consumption condition: 1.49 kWatt for receiving the message and 1.87 kWatt for not receiving the message; t(123) = 1.5, p = .07 (one-tailed). In other words, the environmental attitude-relevance of energy consumption already appeared to be obvious to people high in environmental attitude. Accordingly, for our second contrast, pooling participants from the explicit and implicit salience conditions seemed reasonable. Note that pooling made the subsequent test relatively more conservative given that explicit salience, if anything, enhanced rather than reduced the anticipated effect. The second planned comparison confirmed our theoretically anticipated interaction: Participants with high levels of environmental attitude cooperated significantly more with others in the attitude-relevant (i.e., energy consumption) condition than the participants in the other three conditions combined: t(123) = 2.8, p < .005 (one-tailed), η2 = .06. Evidently, and as predicted, those in the high attitude/attitude-relevant condition took out substantially less than those in the other three experimental groups: the two attitude-irrelevant conditions (points as the resource)

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FIGURE 1 Points/kWatt allocated as a function of people’s environmental attitude and of the attitudinal relevance of the common resource. Note: N = 131 (n = 38, n = 29, n = 36, n = 28; from left to right); vertical bars indicate the 95% confidence intervals.

and even the group with persons low in environmental attitude in the attitude-relevant condition (energy as the resource; see Figure 1). In other words, people with high levels of environmental attitude removed less of the resource if the resource was attitude-relevant (i.e., energy) and, thus, if cooperation meant energy conservation.4 Note that this effect did not depend on the inclusion of the least cooperative people (people in the low attitude/attitude-irrelevant condition; see Figure 1) in the comparison. Participants with high levels of environmental attitude still cooperated significantly more with others in the attituderelevant (i.e., energy consumption) condition than the participants in the other two conditions combined (i.e., the high attitude/attitude-irrelevant and low attitude/attitude-relevant conditions): t(123) = 1.8, p = .04 (one-tailed), η2 = .02. Even more surprisingly, persons high in environmental attitude in the attitude-relevant condition requested significantly less—even in a statistical sense—than what could be seen as their fair share, which is noticeable in Figure 1 (for more details, see Cumming & Finch, 2005): The 95% confidence interval of the average amount of energy demanded by people with high environmental attitudes (M = 1.68 ± 0.26) did not cross the line of social justice (indicating the fair share). Thus, these people engaged in self-sacrifice as they requested less than two units of the resource (i.e., their fair share) on average. This finding was not only an aggregated effect across the 10 rounds of the social dilemma game. As the only ones out of the four experimental groups, the participants with high levels of environmental attitude in the attitude-relevant condition engaged in self-sacrifice from the first round on with an average request rate below the line of social justice. Apparently, self-sacrifice was their norm, although the learning experience of the environmentalists in the environmental attitude-relevant condition paralleled the experience of the members of the other three experimental groups. This correspondence in learning was reflected by a gradual decline in the average demand that was similar across all four experimental conditions for the 10 rounds of the dilemma game.

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Our main finding even held when we controlled for social value orientation. In a supplementary ANOVA with social value orientation (prosocials/proselfs), environmental attitude (high/low), and attitude-relevance (energy/points) as its factors, we did not find that social value orientation significantly affected cooperation: F(1, 108) = 0.1, p = .70. Again, the attitude/attitude-relevance interaction remained significant: F(1, 108) = 4.9, p < .01, η2 = .09. Evidently, it is a person’s level of general commitment to environmental protection in combination with the specific nature of the resource and not their social value orientation that determined cooperation in our social dilemma game.

DISCUSSION Corroborating Campbell’s paradigm, we found that a general attitude (i.e., people’s environmental attitude) significantly determined performance in a demanding and overt specific individual behavior (i.e., cooperation in a social dilemma game). However, as we had expected, this occurred specifically when the behavior involved kWatt rather than points as the resource in question. To our knowledge, this is the first time that environmental attitude (derived from mere selfreports) has been found to significantly promote cooperation in an experimentally simulated social dilemma (cf. Smith & Bell, 1992). Although the environmental relevance of energy did not have to be made salient to be apparent to participants high in environmental attitude, stressing this connection would probably have increased the effect. In other words, using a video message that connects energy consumption with environmental hazards to make people explicitly aware of their environmental attitudes presumably exacerbated the effect. Attitude awareness might even explain the occurrence of the effect in the condition without a video message. Participants in this condition also played for kWatt (i.e., the power unit in physics), which in turn could have implicitly made the link to energy, energy consumption, and, hence, to a person’s environmental attitude salient. The question of whether awareness of one’s environmental attitude is indispensable for driving conduct or not has to be left to future research to disentangle. Conventionally, the inclination to cooperate with others in social dilemmas is expected to originate from individuals’ prosocial orientation (Gifford & Hine, 1997). Accordingly, cooperation with others traditionally means dividing the resources into fair portions and extracting one’s fair share. From a social justice point of view, self-sacrifices in terms of cooperation below one’s fair share and below the replenishable rate would be unreasonable. However, we observed such a result in Study 1. On average, participants with high levels of environmental attitude removed significantly less energy than their fair share as dictated by the pay-off function (indicated by the line of social justice in Figure 1). Environmentalists playing for energy already started below their fair share and never rose above the line of social justice in any of the 10 rounds of the dilemma game. It would be logical to assume that the social dilemma would even disappear if only environmentalists were involved in the consumption of energy. Necessarily, any dilemma involves two unfavorable outcomes: the destruction of the environment or the forfeiting of self-interest. With environmentalists, one can expect that self-sacrifice (cf. Hardin, 1968), which means forfeiting self-interest, is the lesser concern. Accordingly, we found that persons with an unusually high environmental attitude self-sacrificed even under artificial experimental conditions. The effect remained irrespective of people’s social value orientation

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(van Lange, 1999), which is probably the most predictive universal psychological determinant that has been found in social dilemmas to date (Gifford & Hine, 1997).

STUDY 2 According to the Campbell paradigm, demanding behaviors require marked levels of attitudes. Thus, if we wish to forecast differences in general attitudes on the basis of whether a person engages in or reports engaging in a specific behavior or not, we need quantitative knowledge about the difficulty of the behavior in question. Arguably, previous attempts to forecast attitude levels from behavioral records have failed because behavioral difficulties were disregarded (see Ajzen et al., 2004; Sheeran, 2002). In Study 2, like Sheeran (2002) and Ajzen and colleagues (2004), we compared consistent environmentalists (i.e., self-reported vegetarians) and inconsistent environmentalists (i.e., selfreported nonvegetarians). Our behavioral choice was determined by two facts. First, in previous research, we found that self-reports of behavior had a reasonable overlap with people’s actual behavior (see Kaiser, Frick, & Stoll-Kleemann, 2001). Second, a vegetarian diet is one objective and effective way to reduce one’s ecological footprint according to experts in industrial ecology (Taylor, 2000). At the same time, only about 4–7% of the population in most Western societies commit themselves to such a diet (e.g., Nederlandse Vegetariërsbond, n.d.; Stahler, 2006). Such a low popularity of engagement in a vegetarian lifestyle makes the majority of people in Western societies appear to be environmental hypocrites (i.e., inconsistent environmentalists) as Western societies have been found to verbally express high levels of environmental concern (Dunlap, 2002). According to the Campbell paradigm, the low popularity of vegetarianism—an objectively resource-conservation-relevant performance—by contrast, speaks predominantly of the apparent difficulty of maintaining such a diet in Western societies (irrespective of whatever might cause this difficulty). On the basis of the logic of the Campbell paradigm, we anticipated that active vegetarians would hold a comparatively higher environmental attitude than nonvegetarians due to the fact that vegetarians had been successfully maintaining such a diet in their daily lives. In Study 2, we compared the environmental attitudes of self-declared vegetarians and nonvegetarians. On the basis of our rather rough approximation of the difficulty of the target behavior, we hypothesized that self-declared vegetarians (i.e., the attitude-relevant, specific behavior) would display higher levels of environmental attitude (i.e., the general attitude) than nonvegetarians.

METHOD Participants and Procedures Participants were recruited via a free monthly newsletter sent to subscribers of the online Vegetarian Journal (www.vrg.org/journal) published by the Vegetarian Resource Group. The Vegetarian Resource Group is a nonprofit American organization dedicated to educating the public about vegetarianism and related issues such as health, ecology, ethics, and world hunger. In the May 2006 newsletter, we invited subscribers to participate in a survey, and we provided a link

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to the study on the Internet. For each participant, the order of questions was arranged arbitrarily. As an incentive, a vegetarian recipe was posted. Of the 227 people who originally agreed to participate, 222 respondents with a mean age of 39.3 returned a completed questionnaire. The vast majority were female (89.3%); only 24 individuals were male (10.7%). Of the 222 participants, 177 (79.7%) were self-declared vegetarians; 45 (20.3%) were nonvegetarians. Evidently, we dealt with a biased sample in terms of gender, vegetarianism, and most likely environmental attitude as well. For the present purpose, representativity of the sample was not a crucial requirement. Thus, it was sufficient that the sample was without indication of severe restriction of range on the dependent variables, particularly on the two environmental attitude measures. We had no concerns given the unremarkable kurtosis values of 1.7 (NEP) and of –0.1 (GEB). On the basis of their responses to the following three dichotomous statements, we classified the 177 vegetarians concerning the extent of their devotion to vegetarianism: (1) I am a vegetarian, (2) I do not eat honey, and (3) I do not wear leather shoes. Basic vegetarians (n = 50) were the ones who answered only the first statement affirmatively. Advanced vegetarians (n = 60) were the ones who declared being vegetarians (Statement 1) and also refused either to eat honey (Statement 2) or to wear leather shoes (Statement 3). Extreme vegetarians (n = 67) were the ones who answered all three statements affirmatively. Measures Environmental attitude was measured in two distinct ways. One instrument, the New Ecological Paradigm (NEP) scale, is a conventional and often-used environmental attitude measure in environmental psychology (Dunlap, Van Liere, Mertig, & Jones, 2000). As with all such nonCampbellian measures, the item difficulties are not generalizable across persons and, thus, they do not represent a transitively ordered class of indicator items. For the other instrument, the Campbellian attitude measure, we again used—as in Study 1—the 50 self-reported proenvironmental behaviors from the General Ecological Behavior (GEB) scale (Kaiser & Wilson, 2004). With the non-Campbellian NEP, we followed conventional procedures and had our participants rate each of 15 items on a 5-point scale ranging from 1 (strongly disagree) to 5 (strongly agree). Typical item examples are: “Humans are severely abusing the environment” and “Humans were meant to rule over the rest of nature” (i.e., a negatively formulated item). We reversed the coding of the seven negatively formulated items and calculated mean scale scores for each person. We found a mean NEP score of 4.23 (SD = 0.46; range: from 2.25 to 5.00). The 15 NEP items turned out to be internally consistent with a Cronbach’s α of .71. As in Study 1, we followed the recommended procedures for calibrating the GEB instrument (e.g., Kaiser & Wilson, 2004). Another typical item example is “I buy seasonal produce.” Of the behavioral self-reports, 19 represented nonengagement in pro-environmental activities; such negatively formulated items were reversed in their coding. Engagement in 18 behaviors was verified with a yes/no format and in 32 behaviors with a 5-point frequency scale ranging from 1 (never) to 5 (always). The responses to the latter set of items were recoded into a dichotomous format by collapsing never, seldom, and occasionally into unreliable pro-environmental engagement. Often and always were collapsed into reliable pro-environmental engagement. This type of recoding of the behavioral self-reports into a dichotomous format has proven to diminish measurement error

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rather than substantive information relevant for a valid assessment of interindividual differences in people’s attitudes (see Kaiser & Wilson, 2000). The extent of a person’s attitude was—as in Study 1—determined in the typical manner for a Rasch scale based on a maximum likelihood approach. The reliability of the Campbellian environmental attitude measure was rel = .78. The correlation between the NEP and GEB was r = .32, which corresponds to rcorr = .43 when corrected for measurement error (for calculation details, see Charles, 2005).

RESULTS To test our hypothesis that self-declared vegetarians should, on average, be higher in their environmental attitude than self-declared nonvegetarians, we computed two separate ANOVAs: one with the NEP and one with the GEB as the dependent environmental-attitude measure (see Figure 2). With the NEP, the conventional and thus non-Campbellian measure of environmental attitude, we found that vegetarians and nonvegetarians did not differ significantly in their general environmental attitude: M veg = 4.22 versus M nonveg = 4.25; F(1, 220) = 0.9; p = .77. When we additionally distinguished vegetarians by the extent of their devotion, we nonetheless found a marginally significant difference: F(3, 218) = 2.5; p = .06; η2 = .03 (see Figure 2). Post hoc comparisons (employing Scheffe tests) revealed that the difference between basic and extreme vegetarians could be held accountable for this statistical attitude effect (p = .06).

FIGURE 2 Environmental attitude (measured with the NEP or GEB) as a function of the extent of people’s self-reported vegetarianism. Note: N = 222 (n = 45, n = 50, n = 60, n = 67; from left to right); vertical bars indicate the 95% confidence intervals.

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For the GEB, the Campbellian measure of environmental attitude, and in contrast to the NEP, we corroborated our expectation that vegetarians and nonvegetarians would differ significantly in their general environmental attitude: F(1, 220) = 4.0; p = .05; η2 = .02 (M veg = 0.46 vs. M nonveg = 0.18). When vegetarians were additionally distinguished concerning the extent of their devotion, we even found that the linear trend was significant: F(1, 218) = 8.8; p = .003; η2 = .05 (see Figure 2).

DISCUSSION With this study, we found that self-declared vegetarians significantly outperformed nonvegetarians in their average General Ecological Behavior (GEB) score, a measure of general environmental attitude grounded in what Kaiser et al. (2010) call the Campbell paradigm. As in previous investigations (Ajzen et al., 2004; Sheeran, 2002), no substantial attitudinal difference was found with the New Ecological Paradigm (NEP) scale, which is a non-Campbellian and probably the most frequently used environmental attitude measure in environmental psychology to date. Inconsistency or hypocrisy—that is, professing a pro-environmental attitude while simultaneously not engaging in an attitude-relevant specific behavior—only occurred with the traditional non-Campbellian attitude measure (i.e., the NEP) but not with the Campbellian attitude measure (i.e., the GEB). Our findings in Study 2 again supported the Campbell paradigm, a conception of attitude as an inferred property derived from a difficulty-based transitive ordering of attitude-relevant performances, including self-reports of performances. In this paradigm, it is mandatory that one can both (a) predict engagement in a specific attitude-relevant behavior from a person’s general (e.g., environmental) attitude, and, vice versa, (b) predict differences in levels of a general (e.g., environmental) attitude on the basis of whether or not a person engages in a specific attituderelevant behavior. Such predictions require knowledge about the attitude-relevance of the specific activity and about the difficulty of the behavior—in this case, approximated by the prevalence of a vegetarian lifestyle. Such predictions also require that the difficulty of a behavior be generalizable across persons (see Kaiser et al., 2010). In a sample in which approximately 90% of the participants were female and 80% were selfdeclared vegetarians, selection bias is an issue. The way we recruited our participants may explain this otherwise surprising self-selection: Most likely, only people who were at least minimally attracted to vegetarianism took part in our study. Consequently, even our control group might have consisted of people tending toward a vegetarian lifestyle. In other words, even the controls did not represent extreme nonvegetarians. This probably resulted in somewhat less marked attitude differences, thus making the empirical comparison of attitude-consistent (i.e., vegetarians) and attitude-inconsistent actors (i.e., nonvegetarians) more challenging for us. Expectedly, the presumed attitude difference would likely turn out to be more pronounced with a less biased sample.

GENERAL DISCUSSION In this article, we provided two essential pieces of evidence that we hope will help to instigate a paradigm shift in attitude research (see Kaiser et al., 2010), but we are well aware that much more

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evidence will be needed for such a shift to eventually occur. With our research, we challenged the typical hypocrisy expectation that dominates the state-of-the-art understanding of the attitudebehavior relation in contemporary attitude research. According to Ajzen and Fishbein (2005), one must not expect empirical consistency between a person’s general attitude and his or her specific attitude-relevant behavioral conduct. Inconsistency is as likely and, thus, hypocrites (i.e., attitude-inconsistent actors) are not expected to differ in their general attitudes when compared with attitude-consistent actors (see e.g., Ajzen et al., 2004). The Campbell paradigm provides a conceptual alternative to the traditional understanding of the attitude-behavior relation in contemporary attitude research. In this paradigm, attitudes are inferred from behaviors (in our case, self-reports of behavior) and, thus, attitudes are formally rather than causally related to behavior (Kaiser et al., 2010). The measurement of attitudes, hence, requires that attitudes be derived from a transitively ordered class of specific attituderelevant behaviors (see e.g., Kaiser, 1998; Kaiser et al., 2007). Accordingly, we argue that the inconsistency or hypocrisy so often found in attitude research is a conceptual conundrum rooted in portraying the attitude-behavior relation as a causal rather than a formal one and in disregarding the figurative costs involved in realizing a specific behavior. This formal relation between the general attitude of an individual and that person’s specific behavioral engagement can be mathematically captured with the Rasch model (see Formula 1):  ln

pki 1 − pki

 = θ k − δi .

(1)

According to the Rasch model, the engagement probability5 of a specific behavior i is equated with the arithmetic difference between a person k’s general attitude (θk ) and the composite of the behavioral costs epitomized by the difficulty estimate of behavior i (δi ; see Formula 1). Attitudes for persons and difficulties for behaviors are directly inferred from the relative frequencies of the behavioral self-reports under scrutiny. Correspondingly, people are distinguishable with respect to the extent of their general attitudes, and specific behaviors are distinguishable by how demanding such behaviors are to implement. (Note that in Rasch scale calibrations, the accuracy of the Rasch model—attitude and difficulty estimates included—to anticipate the data is tested empirically.) In Study 1, on the basis of a Campbellian measure of people’s environmental attitude, we were able to forecast cooperation in a social dilemma game. We corroborated our prediction despite the highly artificial nature of the setup: sitting in front of a computer in a cubicle playing a game for attitude-irrelevant point earnings or attitude-relevant amounts of energy. In Study 2, we found that performers and nonperformers of an objectively demanding pro-environmental and, thus, attitude-relevant behavior, differed in their general environmental attitudes as long as the attitudes were measured with a Campbellian instrument. Simultaneously, we also replicated the usual finding of hypocrisy with a conventional, non-Campbellian environmental attitude measure (i.e., the NEP: see Dunlap et al., 2000). Evidently, hypocrisy is more apparent than real as it disappears when environmental attitudes are derived from a set of self-reports of pro-environmental behaviors. Predicting specific attitude-relevant behavior with a behavior-based general attitude measure raises logical circularity concerns (e.g., Greve, 2001). Such concerns do not apply to the research reported in this article. In our two studies, we also went beyond solely connecting past with

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future behavior. In Study 1, we tested a nontrivial hypothesis; we predicted a specific attituderelevant behavior (i.e., choosing a cooperative option in a social dilemma when playing for energy) that was not already part of the original Campbellian measure of general environmental attitude (see Kaiser & Wilson, 2004). In Study 2, we tested a second nontrivial hypothesis; we predicted differences in general environmental attitude on the basis of whether a person reported engaging in or not engaging in an objectively but not obviously attitude-relevant specific behavior (i.e., vegetarianism), which was also not part of either of the two general attitude measures employed. From these two tests of the Campbell paradigm, we conclude that the notion of apparent hypocrisy in contemporary attitude research presumably derives from an inappropriate causal and deterministic view of the attitude-behavior relation. Although people’s attitudes are defined by the attitude-relevant class of specific behavior in the Campbell paradigm, this inseparability of attitude and behavior does not require that a behavior be deterministically implemented (a weakness of Campbell’s original 1963 measurement proposal). The fact that individuals differ in their abilities to perform certain acts, that they have unique life circumstances, and that they can choose from various behavioral options to implement their attitudes creates irregularities that speak against a deterministic view. For instance, if an experimenter provides a certain opportunity to reveal pro-environmental engagement in the lab (e.g., separating waste), a research participant might fail to do so, but she or he might nonetheless take the staircase rather than the elevator to reach the lab (a behavior beyond the scope of the experiment). Allowing for such irregularities implies that we cannot do better than model the probability of engagement in an attitude-relevant behavior, which is the probabilistic alternative to Campbell’s original proposal (see Kaiser et al., 2010). As a consequence of implementing Campbell’s idea with a probabilistic measurement alternative, hypocrisy is only apparent; it can be seen to lie in the eye of a deterministically thinking beholder rather than in the stochastic implementation of an attitude by a performer who has a variety of options for manifesting an attitude with the given personal skills and life circumstances. Thus, with the Campbell paradigm and a proper assessment of individual attitudes—based on a broad range of attitude-relevant behaviors (verbal or otherwise)—there is no room for hypocrisy: People express their general attitudes with specific practices, and, vice versa, general attitudes can be derived from specific practices.

ACKNOWLEDGEMENTS We wish to thank Oliver Arnold, Siegmar Otto, Terry Hartig, Robert Scherer—the executive editor—and two anonymous reviewers for helpful comments on earlier versions of this article, and Jane Zagorski for her language support.

FUNDING This research was supported by a grant from the J. F. Schouten Graduate School of User-System Interaction Research at Eindhoven University of Technology, Eindhoven, The Netherlands.

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NOTES 1. Note that we exclusively use the term hypocrisy in its colloquial meaning for verbally professing a general course of action (e.g., doing something for the environment) without implementing corresponding behaviors. 2. Employing general instead of specific measures of attitude as well as of behavior is the traditional way to improve the correspondence between attitude and behavior (e.g., Weigel & Newman, 1976). However, such aggregate measures are not the solution to hypocrisy, which refers to general attitudes’ inability to anticipate specific behavior, and vice versa: engagement or nonengagement in a specific behavior to anticipate differences in general attitude. 3. Logits stand for the natural logarithm of the engagement/nonengagement probability ratio across the entire response vector of a person. The smaller a logit value, the lower the particular person’s environmental attitude. 4. In addition to the anticipated interaction, one can also recognize an unanticipated main effect in the data. Specifically, people high in environmental attitude harvested less from a resource in general, independent of the condition, t(127) = 3.3, p < .05, η2 = .08. We refer the reader to Kaiser and Byrka (2011) for the discussion of this post hoc test, the tentative findings, and related evidence that suggests that environmentalists have a tendency to act prosocially in general. 5. Technically correct, it is not the engagement probability (pki ) but the natural logarithm of the ratio of the probability (pki ) that person k reports to engage in a specific behavior i relative to the probability that person k reports to not engage in behavior i (1-pki ).

AUTHOR NOTES Florian G. Kaiser is a Professor of Personality and Social Psychology at the Otto-von-Guericke University, Magdeburg, Germany. His research interests include theory and measurement of individual behaviors and attitudes (particularly with respect to nature conservation and environmental protection), psychological policy support, and large-scale behavior change. Katarzyna Byrka is an Assistant Professor in the Social Psychology Department at the University of Social Sciences and Humanities, Wroclaw, Poland. Her research primarily focuses socio-psychological phenomena that can be employed in domains of environmental conservation and health promotion.

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Received February 21, 2014 Accepted August 11, 2014

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