A Comparison of Three Psychometric Values Measures for Modeling Ecologically Conscious Consumption Behavior

We model environmentally conscious consumption behavior (ECCB) with three psychometric values constructs: Schwartz’s Self-Transcendence Values, Kahle’s List of Values, and Richins and Dawson’s Materialism. Comparison of competing models and non-nested specification tests lead to a statistically significant model of ECCB which reasonably fits our author-designed and collected survey data. In addition, benevolence and universalism (elements of Schwartz’s construct), and acquisition centrality (an element of Materialism) exhibit statistical significance and conform to expectations.


Introduction
With the advent of reference dependent preferences [1], "arbitrarily coherent" demand [2], and laboratory experiments revealing limited support for the neo-classical, preference-based model of consumer choice [3], researchers might welcome an alternative, stable construct on which to base models of consumer behavior. Values-"desirable transsituational goals… that serve as guiding principles in the life of a person…" ( [4], p. 21)-offer one such alternative. Values "can motivate action…" ( [4], p. 21) and have long been regarded as influencing individual attitudes, beliefs, and behaviors [4] [5] [6].
Environmentally-linked purchase behavior offers an attractive test case for linking values and behaviors. Environmental psychologists have found that separately and as a group, add explanatory power to a model of ECCB compared to a model based solely on socio-demographics. Neither LOV nor Materialism improves model fit, though one element of Materialism, acquisition centrality, does. These findings: 1) suggest psychometrics can enhance models of environmentally-linked consumer behavior and 2) emphasize the importance of construct selection in a values-based approach to modeling. Section 2 below develops the constructs we explore and our research hypotheses. Section 3 describes our sample and survey, while Section 4 describes the resulting data. Section 5 reports the statistical analysis. Section 6 concludes.

Ecologically Conscious Consumption Behavior
Roberts [9], [12] suggests separating socially responsive consumption into one category focusing on environmental awareness and another focusing on other aspects of social concern, e.g., donations to charities, hiring of minorities, and other socially conscious activities. We follow this convention and report in this note analysis of environmentally-linked behaviors (ECCB); other socially-oriented behaviors are reported elsewhere. Schwartz [4], [6] posits ten values: self-direction, stimulation, conformity, tradition, security, achievement, power, universalism, benevolence, and hedonism. As other-regarding constructs, benevolence and universalism offer the most promise for enhancing our understanding of ECCB. Schwartz [6] defines benevolence to focus on the welfare of people with whom one frequently interacts-one's ingroup. The motivational goal behind benevolence is the "preservation and enhancement of the welfare of people with whom one is in frequent personal contact" ( [6], p. 39). Schwartz ([6], p. 12) defines universalism based on the motivational goal behind its manifestation: "understanding, appreciation, tolerance, and protection for the welfare of all people and for nature." Schultz and Zelezny [13] examined the relationship between environmental attitudes and Schwartz's measures, finding that environmental attitudes con-

The LOV
Kahle [10] developed a nine item List of Values (LOV)-sense of belonging; excitement; warm relationships; self-fulfillment; being well-respected; fun and enjoyment of life; security; self-respect; and a sense of accomplishment. Items are measured on a nine point scale anchored by Very Unimportant (1) to Very Important (9). Kamakura and Novak [14] classified the LOV into five motivational domains: self-direction (LOV's self-respect and self-fulfillment), achievement (accomplishment, well-respected), enjoyment (fun and enjoyment, excitement, warm relationships), maturity (belonging, warm relationships), and security (security). As Schwartz [4], [6] merged his maturity value with other values dealing with the welfare of outgroups and nature, we postulate LOV's maturity measure bears a similar relationship: H 3 : Individuals with high levels of maturity engage in more ECCB.
The literature suggests that security is related to anthropocentric attitudes [13]. Thus, H 4 : Individuals with high levels of security engage in less ECCB.
Schwartz and Bilsky ( [5], p. 552) describe individuals high in self-direction as imaginative, independent, intellectual and logical who "refer to reliance on and gratification from one's independent capacities for decision making, creativity, and action." The more a consumer's perception of an organization (or product) corresponds to the individual's self-definition, the stronger the consumer-organization identification [15]. Since consumers' comparisons are likely based on human traits such as norms and values, we postulate: H 5 : Individuals with high levels of self-direction engage in more ECCB.
Kamakura and Novak's [14] achievement and enjoyment serve individual interests; consequently, H 6 : Individuals with high levels of achievement engage in less ECCB, and H 7 : Individuals with high levels of enjoyment engage in less ECCB.

Materialism
Materialism consists of success, acquisition centrality, and pursuit of happiness [11]. Success addresses the notion that people often judge their own and others' success by their possessions. Acquisition centrality refers to the central position material objects hold in the lives of materialistic people. Pursuing happiness through acquiring material objects is a hallmark of materialistic individuals. Richins

Sample
A random sample was drawn from the telephone directory of a large metropolitan area in the Southeastern United States. Potential respondents were pre-called and asked to participate in a study of "Consumer Purchase Behavior." The addresses of those agreeing to participate were verified and a survey and self-addressed, stamped envelope mailed to them. We mailed 290 surveys; 149 were returned, yielding a 51.38 percent response rate. We deleted surveys with missing variables, leaving 141 observations.

ECCB
While Roberts [9], [12], [16] and his colleagues [8] examined a range of environmentally and socially-oriented activities using 40 survey items, we focus on environmentally-related purchase behavior. Items that are repetitive, outdated, or reflect behavior motivated by a desire to save money [9] were excluded, leaving 20 items. These were measured on a 7-point scale anchored by "Never True" (1) and "Always True" (7).

Control Variables
Social desirability was measured by 10 items from the Marlowe-Crowne Social Desirability Scale [17]. These are "true" or "false" items which we summed, with one point per item for the response indicating social desirability. We also measured gender, household income, age, and education.

Values
The three values constructs were included in the survey. Schwartz's [6]  are 60 or older. The median household income range is $50,000 to $74,999.
To determine which items from Robert's instrument (described in Section 3.2.1) capture ECCB rather than other societally-oriented behaviors, we used SPSS to perform a principle components factor analysis using oblimin rotation on the 20 items jointly measuring both ECCB and non-environmental, societally-oriented behavior. The scree plot suggested two factors. We dropped one item which loaded on both factors at the 0.40 level and one which did not load at the 0.35 level on either factor. After deleting these two items, we repeated the factor analysis, resulting in two clean factors capturing 65.57 percent of the variance. The measures of Schwartz's Self-Transcendence Values (universalism: α = 0.90 and benevolence: α = 0.88) and Richins and Dawson's Materialism (success: α = 0.77, acquisition centrality: α = 0.76, and happiness: α = 0.81) also meet accepted standards for Cronbach's alpha. The only measure containing three items in the LOV motivational domain is enjoyment, and its alpha is also acceptable (0.78). Three LOV motivational domains contain two correlated items: self-direction (Spearman correlation coefficient (r) = 0.49, p = 0.00), achievement (r = 0.55, p = 0.00), and maturity (r = 0.51, p = 0.00). For statistical analysis, values variables contain scale means. We also include gender (a dummy variable with gender = 1 indicating female; gender = 0 indicating male) and age in years in subsequent analysis.

Regression Analysis
To determine which, if any, of the three values constructs is linked to ECCB, we first estimated a base model by regressing ECCB on a constant, social desirability, gender, and age. These estimates are reported in columns two and three of Table 2. Then, we estimated three models which augment the base model with variables representing the Self-Transcendence Values (columns four and five of Table 2), the LOV (columns six and seven), and Materialism (columns eight and nine). Table 2 includes an incremental F-statistic (denoted ΔF) and its associated p-value. This statistic tests the null hypothesis that the added variables as a group do not have explanatory power versus the alternative hypothesis that they do. We also report an F-statistic (denoted F) and p-value testing the statistical significance of the model as a whole (excluding the intercept). To measure model goodness-of-fit, we report the coefficient of determination (R 2 ), adjusted R 2 , and the Akaike Information Criterion (AIC) [19]. To test our research hypotheses, we report the estimated coefficient, standard error, t-value and two-tailed p-value for the explanatory variables. Table 2 columns two and three contain the estimates from regressing ECCB on a constant, social desirability, gender, and age. The goodness of fit measures are R 2 = 0.068, adjusted R 2 = 0.048, and AIC = 0.583. The model is significant at the 0.05 level (F = 3.34, p = 0.021). Aside from the intercept, only gender is significant among the explanatory variables (β = 0.684, t = 3.049, p = 0.003).

Self-Transcendence Model
Incorporating universalism and benevolence increases explanatory power, as

LOV Model
The LOV values are grouped into five motivational domains: maturity, security, self-direction, achievement, and enjoyment. Based on the associated incremental F-test, we fail to reject the null that the estimated coefficients of the added variables-maturity, security, self-direction, achievement, and enjoyment-jointly equal zero (∆F = 0.40, p = 0.848). In addition, the overall model fails to achieve significance (F = 1.48, p = 0.171) or improve fit (adjusted R 2 = 0.027 and AIC = 0.639). Of the explanatory variables, only gender is significant (β = 0.547, t = 2.117, p = 0.036); consequently, we fail to find support for H 3 through H 7 .

Materialism Model
Lastly, we add the three dimensions of Materialism-success, acquisition centrality, and happiness-to the base model. We fail to reject the null that the coefficients of the added variables jointly equal zero (∆F = 1.78, p = 0.154). Note, however, the model as a whole is significant (F = 2.59; p = 0.021), largely due to the individual coefficient of acquisition centrality exerting a negative effect on ECCB (β = −0.310, t = −2.137, p = 0.034), supporting H 9 , while gender positively affects it (β = 0.732, t = 3.176, p = 0.002). We fail to find support for H 8 or H 10 . including fitted values for Self-Transcendence and LOV and obtained a similar result: a suggested final model specification incorporating Self-Transcendence (t = 4.021. p = 0.000), but not LOV (t = 0.919, p = 0.360). Should only a single construct be required, J-tests eliminate LOV at levels of significance less than or equal to 0.360. Levels of significance less than or equal to 0.005 are required to exclude Materialism in favor of Self-Transcendence.

Composite Model
At the more typical 0.05 level of significance, the J-tests suggest including elements of Self-Transcendence and Materialism as explanatory variables. As shown in columns four and five of Table 2, both universalism and benevolence are related to ECCB; however, only one Materialism construct, acquisition centrality, proved significant. Consequently, we estimated a composite model, presented in columns 10 and 11 of Table 2, regressing ECCB on a constant, social desirability, gender, age, universalism, benevolence, and acquisition centrality.
The added variables (∆F = 8.33, p = 0.000) and the overall model (F = 6.10, p = 0.000) are significant at the 0.01 level; the individual coefficients of gender, universalism, benevolence, and acquisition centrality are also significant at the 0.01 level, yielding further support for H 1 , H 2 , and H 9 .

Conclusion
As the composite model indicates, adding universalism, benevolence, and acquisition centrality to the base model improves fit and yields a significant model, demonstrating the potential of a values-based approach to modeling consumer behavior. The composite model is the best fit of the five models presented in Table 2 (R 2 = 0.215, adjusted R 2 = 0.180, and AIC = 0.455), and reveals significant estimated coefficients that conform to expectations. We find a positive relationship between ECCB and universalism (β = 0.526, t = 4.374, p = 0.000, supporting H 1 ) and negative relationships between ECCB and both benevolence (β = −0.454, t = −3.142, p = 0.001, supporting H 2 ) and acquisition centrality (β = −0.307, t = −2.710, p = 0.004, supporting H 9 ) 1 . A significant model and a reasonable fit from an exploratory study such as this suggests further research may yield an increasingly effective addition to the economist's toolkit for building robust models of consumer behavior.