Journal of Environmental Management 135 (2014) 91e99

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Journal of Environmental Management journal homepage: www.elsevier.com/locate/jenvman

An extension of the Theory of Planned Behavior to predict willingness to pay for the conservation of an urban park Natalia López-Mosquera 1, Teresa García*,1, Ramo Barrena 1 Universidad Pública de Navarra, Dpto. Gestión de Empresas, Campus de Arrosadía, 31006 Pamplona, Spain

a r t i c l e i n f o

a b s t r a c t

Article history: Received 15 July 2013 Received in revised form 31 October 2013 Accepted 11 January 2014 Available online 10 February 2014

This paper relates the concept of moral obligation and the components of the Theory of Planned Behavior to determine their influence on the willingness to pay of visitors for park conservation. The sample consists of 190 visitors to an urban Spanish park. The mean willingness to pay estimated was 12.67V per year. The results also indicated that moral norm was the major factor in predicting behavioral intention, followed by attitudes. The new relations established between the components of the Theory of Planned Behavior show that social norms significantly determine the attitudes, moral norms and perceived behavioral control of individuals. The proportion of explained variance shows that the inclusion of moral norms improves the explanatory power of the original model of the Theory of Planned Behavior (32e40%). Community-based social marketing and local campaigns are the main strategies that should be followed by land managers with the objective of promoting responsible, pro-environmental attitudes as well as a greater willingness to pay for this type of goods. Ó 2014 Elsevier Ltd. All rights reserved.

Keywords: Local strategies Moral norms Theory of planned behavior Urban park Willingness to pay

1. Introduction Today, nearly 75% of Europeans live in cities and urban areas, and by 2020 this is expected to rise to 80% (European Comission, 2010). Urban areas are, thus, the places where environmental problems directly affect citizens’ daily lives. However, the role of parks in urban areas is usually undervalued, in spite of their usefulness for a variety of aesthetic, recreational, and sporting purposes, acting as they do as a play area for children, and as peaceful retreat for adults, among others things. This undervaluation of the multiple benefits and services offered by these parks relating to citizen welfare encourages behaviors that are not good for the environment and low economic valuations of their worth when people are asked about their willingness to pay (WTP) for the use and/or conservation of these goods (Cooper et al., 2004; Spash et al., 2009). In Spain this situation is even more pressing due to the scant familiarity of ordinary citizens with the economic valuation of public goods (Del Saz-Salazar and Rausell-Köster, 2008). Recent studies have focused not only on determining whether or not individuals behave in a pro-environmental way but also on determining the factors that underlie these intentions and conducts

* Corresponding author. Tel.: þ34 948 169386. E-mail addresses: [email protected] (N. López-Mosquera), [email protected] (T. García), [email protected] (R. Barrena). 1 Tel.: þ34 948 169396; fax: þ34 169404. 0301-4797/$ e see front matter Ó 2014 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jenvman.2014.01.019

(Ojea and Loureiro, 2007; Spash et al., 2009; Sauer and Fischer, 2010) with the aim of increasing the involvement of citizens in environmental issues and increase the amount of proenvironmental behavior. Initially, the analysis of the nature of pro-environmental behavior focused on the study of socioeconomic factors such as education, gender, age, income and marital status (Olofsson and Öhman, 2006; Torgler and García-Valiñas, 2007). It has also been pointed out that social structural variables explain only modest levels of variance in measures of environmental behavior (Sauer and Fischer, 2010). For this reason researchers have recently turned their attentions to other psycho-social constructs such as attitudes, beliefs and values, and these have turned out to be more successful in predicting pro-environmental behaviors (Hoyos et al., 2009; Spash et al., 2009; Groot and Steg, 2010). This second line of enquiry, which includes the present study, is based on the premise that individuals’ behavior towards the environment is influenced by what they feel and think with respect to the environment and with respect to pro-environmental action (Oreg and Katz-Gerro, 2006; Ojea and Loureiro, 2007). One of the most popular approaches of this second line of enquiry is the Theory of Planned Behavior (TPB) developed by Ajzen (1991). The TPB mainly reflects the attitudes and perceived possibilities necessary to carry out a specific behavior. The TPB posits that attitudes, norms and the perceived behavioral control help better understand environmentrelated behaviors (Ajzen, 1991). However, authors have indicated that pro-environmental behaviors have a moral component that is

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not included in the TPB and that it must be taken into account for an adequate analysis of this type of behavior (Kaiser, 2006; Peters et al., 2011; Han and Hansen, 2012). Thus it has been suggested that studying the influence of the moral obligation component could improve our understanding of environmentally relevant intentions and behaviors. Many of the studies analyzing environmental intentions and attitudes on the part of users have studied them by measuring their willingness to pay (WTP) for park conservation and use (Hoyos et al., 2009; Lo and Jim, 2010; among others). Previous studies have already pointed out that in order to determine respondents’ WTP non-economic factors, such as psycho-social motives, need to be included (Cooper et al., 2004; Sauer and Fischer, 2010). This has to do with a lack of habit when it comes to valuing public goods monetarily and to a great lack of information and inexperience in valuing them in relation to market goods. Thus, when they reply to WTP questions, people tend to resort to intuitive feelings regarding public goods (Ajzen and Driver, 1992). That is, they trust their intuitions, feelings and fundamental values when it comes to revealing their willingness to pay. Hence the need to quantify and include them in the WTP model for public goods. This paper seeks to contribute knowledge to the current environmental economics literature by analyzing how people think and feel about conservation and how these motivations could be a useful tool in finding a better explanation for their intention to perform their economic environmental behavior. By way of an expanded version of TPB, the present investigation aims to improve our understanding of the psycho-social factors which determine the intention to pay. Additionally, it will examine the contribution of moral norms to the understanding of the WTP of citizens for the conservation of an environmental good. The environmental good in question is a Spanish urban park, the Taconera Park, located in Pamplona (Navarre). We draw attention to the importance of investigating visitors’ monetary valuations of the conservation of these areas, and identifying their underlying motivations, in order to determine the level of public involvement in this type of goods and help boost their valuation and conservation. This study differs from previous research in two basic aspects. The first concerns the model of study used, an expanded version of TPB which relates the original components of TPB among themselves and also includes the moral norms in order to study their relationship with the original components of TPB and the behavioral intention in itself. Secondly, it must be pointed out that up to now the literature has included various expanded versions of TPB in order to explain other forms of pro-environmental intentions such as willingness to reduce personal car use (Nordlund and Garvill, 2003); recycling intentions (Mannetti et al., 2004) and willingness to pay for improving biodiversity (Spash et al., 2009) or for recreational benefits of urban forests (Bernarth and Roschewitz, 2008). However, up to now there have been no studies using this expanded model of TPB to examine the intention to pay for the conservation of an urban park; únicamente se ha aplicado el modelo original de la TPB (Karppinen, 2005; Bernarth and Roschewitz, 2008). The paper is organized as follows. Section 2 presents the theoretical framework. In Section 3, the data and survey methodology are presented. The analytical model results are presented in Section 4. Section 5 contains the discussion and Section 6 summarizes the main conclusions. 2. Theoretical framework and research hypothesis The TPB psycho-social model, which has origin in the fields of Psychology and Sociology, is grounded in self-interest and rational choice based deliberation, it is a model which mainly reflects the

attitudes and perceived possibilities necessary to carry out a specific behavior (Ajzen, 1991). It is safe to state that the TPB model reflects the respondent’s future willingness to change his or her attitudes and norms in response to circumstances perceived to have individual pay-back. The TPB is an extension of the theory of reasoned action (Ajzen and Fishbein, 1980) made necessary by the original model’s limitations in dealing with behaviors over which people have incomplete volitional control (Ajzen, 1991). According to the original TPB model, the most proximal predictors of behavior are behavioral intentions, which in turn are anteceded by (a) attitudes which reflect the individual’s positive or negative appraisal of a behavioral option; (b) a subjective or social norm, the social pressure from reference group members to enact the behavior and (c) perceived behavioral control, which refers to the perceived ease or difficulty of performing the behavior. As a general rule, the majority of studies have indicated that a more positive attitude and subjective norm and greater perceived behavioral control should strengthen the individual’s intention to perform the behavior under consideration (Ajzen, 1991; Liebe et al., 2011). To date, the original TPB model has been successfully used in environmental studies to analyze various behavioral intentions and behaviors such as recycling (Tonglet et al., 2004); intentions to engage in environmental activism (Fielding et al., 2008) or intentions to use natural reforestation (Karppinen, 2005). Few studies have analyzed the influence of attitudinal factors on WTP for the use or conservation of different natural resources (Cooper et al., 2004; Bernarth and Roschewitz, 2008; Spash et al., 2009). According to these studies, people who have a positive attitude towards payment for conservation (attitude), who perceive support from their family and peers (subjective norm), and also believe in their own ability to take an active part in the conservation (perceived behavioral control) should be more willing to pay for environmental conservation. Thus, based on the original components of TPB, it was hypothesized that: H1. As attitudes towards payment for the conservation of the park become more positive, a person’s intentions to pay for the park increases. H2. As subjective norms regarding payment for the conservation of the park become more positive, a person’s intentions to pay for the park increases. H3. As perceived behavioral control of payment for the conservation of the park improves a person’s intentions to pay for the park increases. Few studies have examined potential relationships between attitudes, subjective norms and perceived behavioral control, in spite of the high correlations that exist between these variables. Worthy of particular note are the strength of association between attitudes and subjective norms, which suggests subjective norms influence attitudes (Quintal et al., 2010). That is to say, people take the expectations of others into account when they form their own attitudes. It has also been demonstrated that the subjective norm determines the perceived control of behavior (Quintal et al., 2010; Peters et al., 2011). All of which is to say that the social pressure from those people who are important to us also facilitates or inhibits how individuals act. Thus. H4. As subjective norms about payment for the conservation of the park become more positive, a person’s attitude toward the payment becomes more favorable. H5. As subjective norms about payment for the conservation of the park become more positive, a person’s perceived behavioral control toward the payment increases.

N. López-Mosquera et al. / Journal of Environmental Management 135 (2014) 91e99

In spite of the fact that various studies have supported the view that the original constructs of TPB are useful for predicting the environmental intentions and behaviors of individuals, it is evident that TPB still leaves a substantial percentage of variance with no explanation in intention and behavior (Han and Hansen, 2012). For this reason various authors have expanded the original model of TPB to improve its explanatory power (Kaiser, 2006; Bamberg et al., 2007; Peters et al., 2011; Han and Hansen, 2012, among others). As previously pointed out, the TPB model has been the object of much criticism due to the absence of a moral obligation component which would reflect the perception of the individual about the moral correctness or incorrectness of a particular behavior (Ajzen, 1991). As a result, one of the most widely used factors for improving the explanation of pro-environmental behavior has been called personal norm, moral norm or moral obligation (Manstead, 2000). Thus, Thorgersen (1996) has argued that pro-environmental behaviors should be classed in the moral rather than in the economic sphere, given that people evaluate these environmentally relevant behaviors in terms of whether they are correct or not, rather than by balancing personal costs and benefits. Continuing in this line of study, various authors have determined that moral norms determine pro-environmental intentions and behavior and also that they improve the prediction of it (Thøgersen and Olander, 2006; Peters et al., 2011; Han and Hansen, 2012). Other authors, by contrast, have been skeptical of the inclusion of moral norms as a proximal or independent determiner of intention in the environmental area (Kaiser and Scheuthle, 2003; Kaiser et al., 2005). In the case of our study, as the WTP for the conservation of an urban park is an intention likely to contain elements of personal morality and social responsibility, it was considered appropriate to include this variable within the model. Thus, it was hypothesized that, H6. As moral norms about payment for the conservation of the park become more positive, a person’s intentions to pay for the park increases. Furthermore, it has been demonstrated that the moral norm is closely related with subjective attitudes and norms in the context of various behaviors (Conner and Armitage, 1998). Moral norms not only contribute to a better explanation of intentions but also the better predicting of individuals’ attitudes (Raats et al., 1995). Various studies have determined that people’s environmental attitude seems to be determined by moral norms (Kaiser, 2006; Arvola et al., 2008). That is to say, our perceptions of what is good and bad lead to a positive or negative valuation of what conduct to carry out. H7. As moral norms about payment for the conservation of the park become more positive, a person’s attitude towards payment becomes more favorable. It has also been demonstrated that the subjective norm determines the moral norms (Quintal et al., 2010; Peters et al., 2011). That is to say, the social pressure we receive from those around us, those people who are important to us, affects our moral perception about what is and is not correct. This leads us to this study’s eighth hypothesis.

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Figs. 1 and 2, respectively, show the initial and expanded TPB models with regard to WTP. 3. Methodology 3.1. Taconera Park Taconera Park, opened in 1830, is the oldest and best known urban park in Pamplona (Spain). It is located in the historic center of the city and it is surrounded by walls. Visitors can enjoy the presence of a wide variety of exotic trees and bushes within its 9 ha. In the central area of the park there is a small zoo which different kinds of animals. The park also has a dovecote, a cafe, fountains, paths, benches and a playground for children. 3.2. Procedure and measures Prior to the survey, a pilot study was carried out on a sample of 25 subjects to ensure the validity and user-friendliness of the questionnaire. The pilot study was developed and administered in a series of meetings and interviews with experts and focus groups who helped us make minor adjustments. Once the pilot study was carried out a random sampling of citizens of Navarra stratified by age and gender was done. Data were collected in November 2012 in 210 face to face interviews carried out with citizens who were walking through different areas of the park at the time of the survey. On average, respondents took 10e12 min to orally complete the questionnaire with the interviewers’ assistance. The final total of usable questionnaires was 190 with 20 refusals. Thus the return rate was 90.5%. On the basis of the final sample it can be seen that the sample obtained was made of 51.6% men and 48.4% women, aged 36 (35.82 years), 42.9% were university graduates and 67.9% had a middle class income between 1000V and 3000V. Finally, the socioeconomic profile of the sample matched the profile of the local population (Instituto Navarro de Estadística) in terms of average age (40.5 years) and gender (49.77% men; 50.23% women). It can thus be concluded that the sample adequately represents the population of Navarra. A four-part questionnaire was used. Part 1 contained questions about citizens’ attitudinal profile. Part 2 covered the question of monetary valuation by means of the Contingent Valuation Method (CVM) to elicit individuals’ WTP (Mitchell and Carson, 1989). Prior to the asking of the valuation questions, the valuation scenario was set out for respondents in as clear a manner as possible. They were thus reminded of the main services it offers to citizens (recreational, health and environmental) and the diversity of flora and fauna it possesses. Respondents were then asked to indicate their willingness to make a financial contribution towards the conservation of the park by means of an obligatory annual household tax that would be managed by the regional government. In Spain the

H8. As subjective norms about payment for the conservation of the park become more positive, a person’s moral norm towards payment becomes more positive. Finally, not only will the direct effects of the psycho-social factors on WTP be examined but the indirect effects that occur between them will also be looked at and this leads us to this study’s final hypotheses. H9. Subjective norms indirectly influence WTP through attitudes, moral morals and perceived behavioral control. H10. Moral norms indirectly influence WTP through attitudes.

Fig. 1. Initial model based on the original components of TPB to explain WTP. Circles denotes latent constructs, squares denote observed variables.

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N. López-Mosquera et al. / Journal of Environmental Management 135 (2014) 91e99 Table 1 Distribution of WTP responses. WTP

Taxes

Positive Real zero Protest zero Total

Total

15V

30V

45V

28 (44.4%) 18 (28.6%) 17 (27.0%) 63

25 (39.1%) 18 (28.1%) 21 (32.8%) 64

11 (17.5%) 27 (42.9%) 25 (39.7%) 63

64 (34%) 63 (33%) 63 (33%) 190

The mean WTP is calculated by

ZT Fig. 2. Expanded model of the TPB to explain WTP. Circles denotes latent constructs, squares denote observed variables.

mean WTP ¼



 1  Gwtp dW

(1)

0

local population can receive what is known in Spanish as “contribución especial” so that citizens can enjoy the benefits of certain public works (Del Saz-Salazar and García-Menéndez, 2007).2 Furthermore, respondents were reminded of their own spending limitations so that their responses would be as truthful as possible. WTP questions were elicited using the standard yes/no question format in combination with open-ended questions. A control question was added to identify the reasons for respondents’ unwillingness to pay.3 Three taxes 15V, 30V or 45V were selected and uniformly randomly distributed across citizens to ensure independence. The three taxes were set in accordance with other valuations previously made in similar contexts (Del Saz-Salazar and García-Menéndez, 2007) and the recommendations that emerged from the experts during the pre-testing process. The distribution of WTP according to tax values is shown on Table 1. As the cost raises the proportion of respondents willing to pay falls. Thus, people are willing to pay low-medium taxes for the conservation of the park. Environment related questions made up part 3 of the questionnaire (Table 2). All the scales used were adapted from the literature (Tonglet et al., 2004; Thøgersen and Olander, 2006; Bernarth and Roschewitz, 2008) to measure the attitudinal profile of the respondent with regard to payment for environmental conservation on 7 point Likert scales (1 ¼ strongly disagree, 7 ¼ strongly agree). The final part of the questionnaire was used to identify the socio-economic profile of the respondents. 3.3. Data analysis 3.3.1. Econometric model of willingness to pay The mean WTP is calculated through the contingent valuation method (Mitchell and Carson, 1989). WTP was presented in a dichotomous format in which those surveyed were asked to make a hypothetical payment for the conservation of the park. The dichotomous question was followed by two open questions to find the minimum and maximum WTP for each respondent. To calculate the mean WTP a simple model was used based on the work of Hanley et al. (1997).

2

In this study the selected means of payment is a tax, given that it is a payment vehicle to which most Spanish people are familiar. They know when and how the money will be collected, and can plan for this in their budget. This choice eased understanding and acceptance of the CVM scenario on the part of respondents. When no payment vehicle is specified or voluntary forms of payment such as donations are established, individuals have a difficult time planning for the expense since they do not know how or when it will be collected, which leads to lower WTP (Wiser, 2007). Bateman et al. (2003) have already compared different payment vehicles and found that stated that WTP obtained through taxes is substantially higher than the stated amount obtained with voluntary donations. 3 The proposed assessment scenario and the contingent valuation questions are explained in the Appendix 1.

where Gwtp is the distribution function of the true WTP. T is infinite for the true intention to pay and is truncated at some value for the purpose of estimation. 3.3.2. Measurement and structural model Structural equation models were selected to calculate the direct and indirect effects of psycho-social factors on WTP. The current study used AMOS 20.0 to analyze the data with the Maximum Likelihood algorithm. Following Anderson and Gerbing’s (1988) two-step approach, a measurement model was estimated using Confirmatory Factor Analysis (CFA) and Structural Equation Modeling (SEM) was used to test causal relationships. The following fit indices were calculated to determine how the model fitted the data: c2 (chi-square); CFI (comparative fit index), GFI (goodness fit index) and NFI (normed fit index) indices should be close to 0.9 or Table 2 Reliability and Confirmatory Factor Analysis for the expanded TPB model. Scalesa Attitude (a ¼ 0.96) I think the idea of paying to conserve the park is very positive I think the idea of paying to conserve the park is very responsible I think the idea of paying to conserve the park is very intelligent I think the idea of paying to conserve the park is very useful I think the idea of paying to conserve the park is very ecological Subjective norm (a ¼ 0.94) The people who are important to me think that one should pay The people who are important to me expect that I will pay The people whose opinions I value would pay for conservation Moral Norm (a ¼ 0.83) I feel that I should pay for the conservation of the park I feel guilty if I don’t pay for the conservation of the park Perceived behavioral control (a ¼ 0.50) It would be difficult for me to pay to conserve the park I think that me paying wouldn’t improve the current state of the park. I have the resources, time and opportunities to pay for the park.

Mean (s.d.)b

b

3.45 (2.06)

0.93

3.64 (2.01)

0.94

3.23 (1.91)

0.96

3.51 (2.00)

0.90

3.81 (2.09)

0.81

2.87 (1.88)

0.93

2.92 (1.88)

0.95

3.05 (1.80)

0.86

3.07 (2.01)

0.83

2.80 (2.01)

0.84

4.68 (2.17)

0.30

4.35 (1.88)

0.55

3.43 (2.11)

0.82

CR

AV

0.96

0.83

0.94

0.84

0.82

0.70

0.60

0.36

a The items listed in this table have been summarized for ease of presentation and comprehension. b s.d: Standard deviation; b: standard regression weight; a reliability (Cronbach’s a); CR: composite reliability; AV: average variance.

N. López-Mosquera et al. / Journal of Environmental Management 135 (2014) 91e99

1.0 and the RMSEA (robustness of mean squared error approximation) should ideally lie between 0.05 and 0.08. Finally, the Sobel test and a bootstrapping method (with n ¼ 5000 bootstrap resamples) were used to calculate the indirect effects. The Sobel test determines the potency of the mediator by creating a standard error of the effect that the independent variable has on dependent variable vis-à-vis the mediator. A t statistic is generated, and its significance is determined based on the degrees of freedom (n  3) (Sobel, 1982). The SPSS-macro provides an estimate of the true indirect effect and its bias-corrected 95% confidence interval (Preacher and Hayes, 2008).

95

environmental scales such as the perceived behavioral control developed here are sometimes reported with reliabilities below 0.60. For example, a ¼ 0.55 (Oreg and Katz-Gerro, 2006); a ¼ 0.58 (Kaiser et al., 2005); a ¼ 0.59 (Peters et al., 2011). Finally, we performed a test of the scales’ discriminant validity. Scale variables are sufficiently different from one another if a scale’s Cronbach alpha is greater than its shared variance with any other scale variable in the model (Berné et al., 1996). As Table 3 shows, this condition was met in our study. The correlation matrix also showed that all the constructs are highly correlated. Thus all the tests carried out show the reliability and validity of the proposed measurement model.

4. Results 4.3. Hypothesis testing 4.1. Willingness to pay analysis The mean WTP is calculated by integrating a Logit function (1) where the price is cut off on the basis of the maximum WTP offered by respondents (45V) and limited in order to be positive. The results reveal that the mean WTP is 12.67 Euro (ranged from 0 Euro to 45 Euro). The continuous variable provides the dependent variable for the subsequent structural equation modeling estimations. The significance of the bid price variable (b ¼ 0.05, t ¼ 9.91, p < 0.01) suggests the presence of starting-point bias. Additionally, a second Logit model with covariates was used to determine the socioeconomic variables which influenced the WTP of the respondents. A higher WTP for conservation was obtained from citizens with a higher income (b ¼ 0.91, t ¼ 7.80, sig 0.10) and perceived behavioral control (b ¼ 0.13, t ¼ 1.47, p > 0.10) with WTP could not be confirmed, and so H2 and H3 are rejected. Furthermore the effect that the subjective norm has on attitudes is confirmed (b ¼ 0.73, t ¼ 12.21, p < 0.01) as it is on perceived behavioral control (b ¼ 0.23, t ¼ 2.73, p < 0.01), which leads to the accepting of H4 and H5. The determinants, attitudes, subjective norm, and perceived behavioral control explain 32% of the variance in WTP. The expanded structural model (Fig. 3) has an acceptable model fit (c2 ¼ 131.24, RMSEA ¼ 0.07, GFI ¼ 0.92, CFI ¼ 0.97, NFI ¼ 0.95). The majority of the structural coefficients are again significant (p < 0.01) and personal norm appears to have the strongest effect (b ¼ 0.61, t ¼ 3.59, p < 0.05) on intention to pay followed by the attitudes (b ¼ 0.35, t ¼ 2.23, p < 0.05), so confirming H6 and H1 respectively. However, the relationships between the subjective norm (b ¼ 0.33, t ¼ 1.44, p > 0.10) and perceived behavioral control (b ¼ 0.03, t ¼ 0.30, p > 0.10) with WTP could not be confirmed, so leading us to continue to reject H2 and H3. Furthermore, the effect of the subjective norm on attitudes (b ¼ 0.42, t ¼ 2.67, p < 0.01), perceived behavioral control (b ¼ 0.24, t ¼ 2.62, p ¼ 0.01) and personal norm was confirmed (b ¼ 0.89, t ¼ 13.78, p < 0.01), which leads us to accept H4, H5 and H8. H7, which holds that the personal norm determines the attitudes of citizens to payments (b ¼ 0.35, t ¼ 2.17, p ¼ 0.05) was confirmed. Finally, the determinants, attitudes, subjective norm, personal norm and perceived behavioral control explain 40% of the variance in WTP. 4.4. Mediation analysis To complete the proposed study model, along with the direct effects calculated by way of the studies hypotheses, the existing indirect effects between the constructs was analyzed. As shown in Fig. 2, moral norm, perceived control and attitude mediate the effect between subjective norm and WTP; and attitude mediates the Table 3 Interconstruct correlations.a Attitude Attitude Subjective norm Personal norm Perceived control a

.96 0.73*** 0.72*** 0.18**

Subjective norm

Personal norm

Perceived control

.94 0.88*** 0.14*

.83 0.33***

.50

In bold, the Cronbach’s a; ***p < 0.01; **p < .05; *p < 0.10.

96

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Fig. 3. Structural model of WTP based on the expanded Theory of Planned Behavior model. b: standard regression weight.

effect between moral norm and WTP. Table 4 shows the indirect effects model for each mediator. The significant p-values of the Sobel’s test indicate that all the existing indirect effects are significant, except for behavioral control (p > 0.10). It is thus demonstrated that attitudes (b ¼ 35, t ¼ 5.64, p < 0.01) and the moral norm (b ¼ 0.31, t ¼ 3.78, p < 0.01) significantly measure the effect between the subjective norms and WTP, partially confirming H9. Furthermore, attitudes also significantly measure the effect between the moral norms and WTP (b ¼ 0.30, t ¼ 4.02, p < 0.01), so confirming H10. The bootstrap method also reveals that all the significant mediating effects do not lie between zero for the predicted confidence intervals. Thus, this mediated effects are significantly different from zero at p < 0.01. 5. Discussion Various studies have indicated that the inclusion of additional variables, such as the case of moral norms, substantially improve the explanatory power of the original model of the TPB (for example, Kaiser, 2006; Hunecke et al., 2007). There is consistent evidence that such moral-related concepts significantly contribute to the understanding of behavioral intentions and behaviors in the environmental context (Kaiser, 2006; Peters et al., 2011; Han and Hansen., 2012). However, their quantitative explanatory power has been rarely consolidated empirically (Parker et al., 1995; Harland et al., 1999; Tonglet et al., 2004), showing the necessity for further studies. In this context, therefore, the present study shows that the extended TPB model offers a useful and effective framework to analyze the inter-relationships that exist between attitudes, subjective norms, moral norms and perceived behavioral control. In the same way this extended model helps to identify how these psycho-social determinants motivate the intention to pay for the conservation of an urban park. This study represents, for the first time, the application of the TPB expanded by the addition of moral norms, in the context of urban parks. Therefore, the psychosocial approach developed may be very useful in public decision making.

Prior to the estimation of the path models, the contingent valuation estimates indicated a WTP of 12.67V per year for the conservation of an urban park. The average WTP values obtained in this study are similar to those seen in previous similar studies carried out in urban areas. In Spain, Del Saz and Rausell-Köster (2008) analyzed the non-market benefits derived from the use of a park and obtained a 7.6V/year average WTP. In Europe, Zoppi (2007) evaluated the desirability of three planning scenarios concerning outdoor recreation. He obtained a 16.42V/year average WTP in the “Park for Local Economic Development” scenario, 19.14V/year in the “Auto-organized Park” scenario and 25.95V/year in the “Park as a Service Project” scenario. Finally, in the USA Majumdar (2011) estimated tourists’ WTP for urban forests and obtained a $11.25 average WTP value. Furthermore, it is worth highlighting that only 34% of those surveyed at the Taconera Park declared their willingness to pay for the conservation. This percentage lies within the ranges obtained in other research on urban green spaces, such as Kriström (1997) where 33% of the subjects were found willing to pay and, Del Saz and García-Menéndez (2003) and Adams et al. (2008) where 35% positive WTP responses were obtained and Del Saz-Salazar and Rausell-Köster (2008), who obtained a positive response of 21%. These high percentages of refusal to pay suggest a certain degree of resistance to the bidding format used (bidding bias) and a lack of familiarity in Spanish society with valuation decisions for public goods, as has previously been indicated by other authors (Del Saz and García-Menéndez, 2007; Del Saz-Salazar and RausellKöster, 2008). The fact that out of the 66% of respondents with no WTP, 33% were protests because they felt they already paid too much tax or did not trust the way their money would be used should also be highlighted. Carson (1991) has already pointed out that CVM studies usually obtain a percentage of protests answers of approximately 30%. Having 33% protest votes is quite high, but not totally unknown in other CVM studies with comparable definitions of protest votes (e.g. 47.7% resp., 35% in Del Saz-Salazar and Rausell-Köster, 2008; Bernarth and Roschewitz, 2008). Furthermore, the world economic crisis, which in recent years has affected Spain, has had a negative influence on the WTP of respondents, lowering the amount these individuals are willing to pay for this type of goods. Additionally, it was determined that the socioeconomic profile of respondents influenced their WTP and that WTP was higher among women and among citizens with higher income levels, as also has been found by other authors (Del SazSalazar and García-Menéndez, 2007; Álvarez et al., 2010; Lo and Jim, 2010). In these circumstances, land managers must try to understand which other factors might lead to pro-environmental behaviors in order to obtain more information about the intentions of visitors to these resources. It is thus necessary to examine those motivational factors which determine pro-environmental economic intentions and behaviors, such as, for example, attitudes and moral norms which would lead to encouraging or strengthening this behavior. In order to examine these matters, through the use of an expanded TPB model, the present study examines whether the psycho-social

Table 4 Indirect effects. Independent variable

Mediator

Subjective norm Subjective norm Subjective norm Personal norm

Attitude Perceived behavioral control Moral norm Attitude

***p < 0.01.

Dependent variable

Value

WTP WTP WTP WTP

0.35*** 0.03 0.31*** 0.30***

se

0.12 0.02 0.09 0.07

Mediation confidence interval Lower

Upper

0.09 0.00 0.20 0.18

0.54 0.09 0.54 0.45

Z values

5.64 1.36 3.78 4.02

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motivations of visitors conditions, directly or indirectly, their valuation decisions. If we focus on the influence of each psycho-social construct on WTP, the results differ. Thus, the perception of the individual regarding the moral correctness or otherwise of being prepared to pay for the conservation of the park (moral norm) was found to be the strongest determinant of WTP (H6). The importance of the moral norm for predicting pro-environmental attitudes in individuals has been shown by a number of authors (Thøgersen and Olander, 2006; Peters et al., 2011; Han and Hansen, 2012). The general conclusion reached by them all has been that personal moral norms are a fundamental element in deciding whether citizens will be willing to behave in a pro-environmental way and, thus, this predisposition influences their decisions. In the case of our study the results show that appealing to feelings of personal obligation could be beneficial for directly or indirectly promoting (by way of citizens’ attitudes) environmentally aware behavior, such as, for example, paying for conservation. The next component which showed the greatest influence on WTP for the conservation of the park is the citizens’ attitude to the payments (H1). This supports the results found in previous studies by (Cooper et al., 2004; Ojea and Loureiro, 2007; Spash et al., 2009). It is obvious that citizens are not going to commit themselves to an annual payment for the conservation of an environmental good unless they have a good opinion of such systems and think that they can achieve good results. For this reason it is necessary to reinforce the positive attitudes of those already willing to pay for conservation and to change the attitudes of those who take a negative view of paying for this type of public goods. Furthermore, it was not possible to confirm the direct effect of social pressure on WTP (H2), something that Spash et al. (2009) were not able to confirm either. Arvola et al. (2008) have indicated that social norms may not be appropriate for use with the TPB as they are shared by a group and do not necessarily reflect the individual’s own with regard to behavior. The lack of impact of social norms in the environmental context has been revealed in previous studies (Milfont, 2009) who notes the effect of social desirability concerns is low or even non-existent in environmental behaviors. However, our study has confirmed the indirect effect of the subjective norm on WTP by way of attitude and moral norm (H9), as previously highlighted by (Thøgersen and Ölander, 2006). This means that social norms (or the expectations of others) do not directly affect our behavioral decisions. Social norms, by contrast, do indirectly affect us in the formation of our attitudes regarding complying with the will of others and when we personally evaluate our own actions, for example, being willing or not willing to pay for the conservation of a park. Neither has the effect of perceived behavior control on WTP for conservation been demonstrated (H3). Some authors have cited perceived behavioral control as one of the determinants of WTP for various environmental improvements (Pouta and Rekola, 2001; Spash et al., 2009), while others have found no significant link (Hinds and Sparks, 2008; Fielding et al., 2008). The non-significance of the subjective norm and perceived control in the prediction of WTP indicates that citizens think that they are self-sufficient and have complete control over their own behavior. That is to say, when citizens do not pay for conservation it is because they do not have any intention of doing so, it is not due to a lack of social support or the presence of some inhibiting factors or due to the absence of some of the necessary resources. By focusing on the inter-relations that exist between the psycho-social constructs it can be seen that social and moral norms are significant predictors of the attitudes of citizens with regards to paying for the conservation of the park (H4 and H7), a result that confirms the finding of a previous study (Quintal et al., 2010). This result seems to indicate that people’s attitudes to the behavior of

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conservation are represented by moral and social considerations and that personal interests and rational choice are pushed into the background (Kaiser and Scheuthle, 2003). Thus, moral and social norms may represent the essence of the evaluation of environmental attitudes. The notion that social pressure in the form of subjective norms influences perceived behavioral control and moral norms were also supported (H5 and H8). As such, important referents might have an even greater influence than previously thought. The effect of subjective norms on behavioral control and moral norms has been found in this and other studies (Quintal et al., 2010; Peters et al., 2011). That is to say that external social pressure arising from what others think facilitates or inhibits the way we act and conditions our moral norms or values which determine what we regard as correct or incorrect. (Ajzen, 1991; Manstead, 2000). Finally, it should be noted that our study of the expanded TPB model shows that its components - attitude, subjective norm, moral norm and perceived behavioral control e explain 40% of WTP while the initial model (attitude, subjective norm, perceived behavioral control) explains only 32% of it. It is thus demonstrated that moral norms contribute to a better comprehension of intentions (Manstead, 2000; Kaiser, 2006; Peters et al., 2011; Han and Hansen, 2012). This suggests that none of the original TPB components captures the impact of moral considerations on the intentions to display pro-environmental behaviors. The contribution of moral concepts in the TPB has been the subject of a great deal of controversy in environmental contexts. While the majority of scholars have seen the proportion of variance explained represents an impact in intentions of between 1 and 10% (Harland et al., 1999; Tonglet et al., 2004), others indicate an impact higher than 10% (Parker et al., 1995). These results indicate that the impact of moral norms on intentions probably varies over different domains of pro-environmental behavior as well as social/environmental contexts (Bamberg et al., 2007). In spite of the fact that the moral norm improves the predictive power of the TPB model and explains a reasonable percentage of WTP, a large amount of unexplained variance still remains. It is therefore necessary to consider other causal elements such as socioeconomic factors (income, age or educational level), personal factors (personal capacity, identity, past experiences) and contextual ones (risk factors, environmental uncertainty) to improve the predictive ability of TPB model and to obtain a better explanation of WTP (Stern, 2000). Furthermore, results suggest that there is a decline in the contributions of the original TPB components (attitude, subjective norm, behavior control) when moral norms are included in the model. This result suggests that the inclusion of personal norms can increase the conceptual clarity of TPB in the models related to proenvironmental behavior (Harland et al., 1999). In other words, moral norms adjust the TPB original components by controlling the personal normative impact that they do not capture by themselves. Finalmente, the results found here cannot yet be generalized to all urban parks. The sample used only represents those citizens who were visiting the urban park and for this reason the results obtained might not be repeated for all types of environmental goods. 6. Conclusions These results lend support for the usefulness of incorporating measures which capture affective and moral bases of behavioral intentions into the framework of TPB. As this study has shown, individuals with positive attitudes and strong moral norms show higher WTP for the conservation of an urban park. In this context the main challenge faced by urban managers is to try to re-educate citizens about what must be done and why there is a necessity to

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conserve urban parks. Deepening environmental knowledge could help managers determine which psycho-social factors are important for individuals to be more environmentally active and thus obtain a higher economic valuation for these resources. From a practical point of view, this study provides justification for using a moral dimension in marketing of urban parks. Based on earlier findings, we know that citizens tend to be aware of the positive environmental implications of conservation. This study indicates that many citizens experience conservation payment choice as a morally right thing to do, which provides an internal reward, and this moral feeling further relates to intentions to pay for the conservation of urban parks. With the purpose of extolling the moral duty of citizens towards this type of good it is necessary to communicate these norms to citizens through such external sources as community-based social marketing and local campaigns. These forms of local action could help to promote a sense of personal obligation among citizens which would help increase the possibility that they would pay for urban parks. The idea would be for citizens to see this personal norm as a social one, as a result of these campaigns which would promote a common way of feeling and acting within the local community. It must be remembered that personal norms are in fact internalized social norms (Schwartz, 1977). Communicating social norms could, in the long term, stimulate this internalization. In order for this internalization to lead to more environmentally responsible conduct the messages used must not only provide detailed information but also raise people’s consciousness and try to make them feel more responsible regarding the consequences of not paying for conservation (for example, the deterioration and/or loss of urban parks, reduction of space for recreation and lack of oxygenation). At the same time the local strategies of urban managers can be completed by focusing on “less important” issues like the aesthetics of the area, comfort or the space for leisure activities provided by urban parks, aspects that are very much appreciated by the citizens (Chiesura, 2004). That is to say that the objective should be to design local marketing campaigns that manage to create a link in the minds of citizens between these attributes and paying for conservation. Thus, when the moment for the final decision on payment comes, all these attributes along with the psycho-social factors will encourage the carrying out of this type of pro-environmental behavior. Media outlets such as TV, radio, the printed press, and social networks are useful tools when it comes to promoting knowledge and pro-environmental actions. The mass media can show the benefits and damages of pagar o no por la conservación de nuestros parques and “train” citizens in conservation habits, willingness to pay, etc. thus promoting certain behaviors. These informative strategies are particularly efficient when the pro-environmental behavior involved is relatively simple and does not require much in terms of money, time, effort and external restrictions (Gärling and Schuitema, 2007). With regard to the limitations of this study and to future directions of research, at the theoretical level we would like to point out that it would be interesting to examine the influence of these motivational factors on actual rather than intended WTP. Other ways of making payments such as donation or bid prices could also be considered, instead of the annual taxes. It could thus be determined whether using other payment methods would produce a change in WTP. Secondly, the sample used was made up exclusively of visitors to the park. In order to obtain a more representative sample of the local population it would be interesting to increase the sample size to include non-visitors and increase the size of the sample to include other urban parks. It would then be possible to determine if there exist differences in the environmental profile of users and non-users when it comes to their intentions regarding economic valuation of suburban parks.

Finally, it would be of interest to continue to make advances in the study of the environmental profile of the public through the use of other theoretical methodological perspectives such as Choice Experiments (Adamowicz, 1994) and Deliberative Methods (Zografos and Howarth, 2008) as well as others such as the MeansEnd-Chain Theory (Gutman, 1982). These techniques offer other definitions of the good that is the object of analysis, (for example by differentiating the attributes of the good in question) and postulate that decision-making processes would benefit by the promotion of a debate on environmental values, costs and benefits that could result in a degree of public consensus on environmental policy. Appendix Questions used in the contingent valuation: Valuation scenario. Taconera Park is a small green space in the center of Pamplona. It’s a place for rest and relaxation, with pleasant views and it also has an interesting variety of animal and plant life. It is a place of special interest for bird watchers and as well as the birds that are permanent residents in the park there is also an impressive variety living round and about it. We would now like you to place an economic valuation on the satisfaction or wellbeing that these aspects of the park produce for you, as well as your willingness to make an economic contribution to the conservation of the park. The payment would be made by way of a special, obligatory tax that households would pay on an annual basis. The tax would be paid to the regional government of Navarra. Please try to imagine a real payment and remember that the money that you spend on this tax will not be available for use for other purposes. Valuation questions. Taking into account all the possible benefits provided by the area as a whole, would you be willing to pay a special annual tax of X V? , Yes , No Bearing in mind that you would be willing to pay X V, how much more would you be willing to pay?.....V Bearing in mind that you would not be willing to pay X V, what is the maximum quantity you would be willing to pay?.....V If you are NOT willing to pay, please indicate your reasons by placing an X in the appropriate box

Reason for unwillingness to pay

Score

I already pay enough in taxes This environmental resource is not worth an entrance fee I’m not sure the money would be put to good use I think entrance should be free of charge I couldn’t afford to pay an entrance fee Don’t know/no answer

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