A Causal Path Analysis of Ecological Behavior Relating to Marketing

Lawrence A. Crosby, University of Nebraska
James D. Gill, University of Nebraska
ABSTRACT - A study of voter preference on the Michigan "Bottle Bill" provides new insights into the characteristics of the Ecologically Concerned Consumer and strategies for marketing to this consumer segment. A path model is developed to account for complex interrelationships among the predictors of ecological concern and behavior. The model is based on the environmental behavior literature and psychological theory. The survey results are found to be generally consistent with the model.
[ to cite ]:
Lawrence A. Crosby and James D. Gill (1981) ,"A Causal Path Analysis of Ecological Behavior Relating to Marketing", in NA - Advances in Consumer Research Volume 08, eds. Kent B. Monroe, Ann Abor, MI : Association for Consumer Research, Pages: 630-636.

Advances in Consumer Research Volume 8, 1981      Pages 630-636

A CAUSAL PATH ANALYSIS OF ECOLOGICAL BEHAVIOR RELATING TO MARKETING

Lawrence A. Crosby, University of Nebraska

James D. Gill, University of Nebraska

ABSTRACT -

A study of voter preference on the Michigan "Bottle Bill" provides new insights into the characteristics of the Ecologically Concerned Consumer and strategies for marketing to this consumer segment. A path model is developed to account for complex interrelationships among the predictors of ecological concern and behavior. The model is based on the environmental behavior literature and psychological theory. The survey results are found to be generally consistent with the model.

INTRODUCTION

The decade of the 1970's was a turbulent period in the history of the American marketplace. Major shifts in the economic, political and social climates significantly impacted marketers. During this period serious questions were raised about marketing practices and especially those affecting the natural environment. Many felt that "ecological concern" might pose a threat to marketing by stimulating the passage of more regulation. However, a few astute marketers argued that it was possible to convert this threat into an opportunity through Ecological Marketing. The premise of Ecological Marketing is that a segment of consumers exist who are motivated to buy environmentally safe products and who will respond to an ecological appeal (Banish 1976).

Research was undertaken in an attempt to identify the ecologically concerned consumer segment (see e.g., Anderson and Cunningham 1972, Kinnear, Taylor, and Ahmed 1974, Webster 1975, Murphy, Kangun, and Locander 1978). This research focused on the demographic, personality, and attitudinal correlates of ecological concern that might be relevant to the design of effective communications strategies. Unfortunately, the findings were not very encouraging. It appeared that the ecological concerned consumer (ECC) could be identified but that the segment was small and hard to reach.

Consumer research pertaining to Ecological Marketing has been hampered somewhat by two problems. First, only limited phenomena exist for study because few consumer presently engage in ecological consumption behavior. This has forced researchers to increasingly rely on experimental choice situations that necessarily require some sacrifice in external validity (Murphy 1978, Lepisto 1979, Arndt and Helgesen 1979). The second problem concerns the lack of an appropriate methodology to account for complex interrelationships between the correlates of ecological concern. Multicollinearity among the predictors has generally been viewed as a methodological defect rather than an important source of information about underlying causal influences.

THE RESEARCH APPLICATION

While consumer demand for ecological products may be limited (at present), consumers seem more willing to support the regulation of marketing activity affecting the environment. This is particularly evident in the case of the beverage container problem. Consumers have generally shunned returnable containers in favor of the convenience of throwaways, even though throwaways waste resources and contribute to solid waste and litter. However, in apparent contradiction of this marketplace behavior, consumers in eight states have supported the passage of mandatory deposit laws (the states are Oregon, Vermont, lows, Maine, South Dakota, Connecticut, Michigan, and Delaware).

The present study focuses on the 1976 beverage container deposit law referendum in Michigan. In that election, Michigan voters approved by a substantial margin (64% to 36%) a proposal to require refundable cash deposits for soft drink and beer containers. This election was selected for study because: (1) individuals were acting in their roles as both voters and consumers, (2) a large number of persons were engaging in ecological behavior by supporting the law, and (3) the successful passage of the law was expected to provide some guidance for the marketing of ecological products.

THE METHODOLOGICAL APPROACH

A generalized causal model was developed and tested for its ability to explain and predict deposit law voting preferences. It is suggested that the approach taken to developing and operationalizing the model can be applied to the study of various ecological behaviors. Although the model does not include all possible causal influences, it does include variables representing the most important classes of predictors. Furthermore, the model reflects causal influences among the predictors as well as those between the predictors and the criterion. Thus, both the direct and indirect effects of the predictors on the criterion can be assessed.

THE CAUSAL MODEL

The a priori causal model (see Figure 1) incorporates five levels of variables. The most basic level involves individual differences in demographics and personality. Included at Level 1 are the constructs of socio-economic status (SES) and alienation (ALIEN). The second level contains a political orientation measure of liberalism-conservatism (LIBER) which may reflect important differences in values. Level 3 contains general attitudes or opinion clusters relating to ecological concern (ECI) and concern about the unemployment consequences of environmental protection (JOBS). Level 4 contains more specific environmental and economic attitudes with particular relevance to the deposit law issue. Among these are concern about throwaway containers as a source of litter (LITTER) and concern about the effects of a deposit law on beverage prices (COST). The fifth level incorporates the behavior related variables. Included at Level 5 are variables dealing with voting preferences on the deposit law (VOTE) and previous habits regarding the purchase of returnable containers (RETURN). The criterion variable is VOTE.

The specific causal paths are not shown in the a priori model (Figure 1) because this would create undue complexity in the diagram. Basically, the a priori model assumes that causal influences move from left to right in the diagram and that each lower level variable has a causal path connecting it to each higher level variable. In addition, causal paths are assumed to exist from SES 6 ALLEN and from RETURN 6 VOTE while unanalyzed paths are assumed to exist between JOBS : ECI and between COST : LITTER.

FIGURE 1

A PRIORI MODEL

MODEL JUSTIFICATION AND HYPOTHESES

The causal model was formulated on the basis of theoretical considerations and knowledge of the environmental behavior literature. The purpose of this section is to justify the choice of variables and their level of inclusion in the model.

Numerous researchers have tried to predict ecological concern from demographic and/or personality variables (Anderson and Cunningham 1972, Kinnear, Taylor, and Ahead 197&, Webster 1975, Henion and Wilson 1976, Murphy, Kangun and Locander 1978, Murphy 1978, Lepisto 1979). Demographically, the ECC's tend to be white and have higher incomes, higher status occupations, and higher socioeconomic status although the findings are not very consistent. Socioeconomic status (SES) was included in the present model to determine how this variable influences an entire complex of environmental attitudes and behaviors, not just limited to ecological concern. It was felt this might uncover any countervailing effects tending to suppress the influence of SES.

Socioeconomic statue was positioned at Level 1 as a basic causal influence in the model. It is assumed that individuals of similar social status have shared many of the same learning experiences and that these experiences serve to shape personality, values, attitudes, and behavior. For example, it is predicted the socio-economic status has a negative influence on feelings of alienation (ALIEN). Those who receive the rewards and respect of society and maintain positions of power and influence are less likely to experience feelings of powerlessness, meaninglessness, and social isolation.

Previous studies have produced contradictory findings about the relationship of alienation To ecological concern and behavior. Anderson, Henion, and Cox (1974) found the ECC to be more alienated than the non-ECC person. On the other hand, Nelson (1974) found the ECC to be less alienated. Anderson and Cunningham (1972) found that socially responsible persons were less alienated. It seems reasonable that alienation would exert some influence on environmental attitudes and behavior since alienated individuals tend to feel powerless in helping to solve social problems. Therefore, alienation (ALIEN) was included in the model with the expectation that it would relate negatively to the environmental variables.

The "alienated voter hypothesis" provides another reason for including measure of alienation. Several studies in the political science literature have found that alienation is associated rich political negativism and a tendency to vote against referendum issues like the "bottle ban" (Horton and Thompson 1962, Stone 1965, Aberbach 1969). Alienation was also positioned at Level 1, as a basic causal influence in the model. Personality is thought to be a determinant of a person's political orientation (Adorno, et. al. 1950) and attitudes (Katz 1960). Also, personality is often tied to the concept of "consistent responses to the world of stimuli surrounding the individual" (Kassarjian 1971) suggesting a link to behavior.

There is some evidence in the literature of marketing (Webster 1975, Mayer 1976) and environmental behavior (Tognacci et. al. 1972, Constantini and Hanf 1972, Dunlap 1975, Koenig 1975, Buttel and Flinn 1976) to suggest that liberals are more ecologically concerned than conservatives. Such a relationship might be expected since most environmental programs involve some form of government intervention. Since this was also true for the Michigan deposit law, it justified including a measure of political orientation in the model (LIBER).

The LIBER variable was positioned prior to the other attitudinal variables at Level 2 on the basis of its "centrality." A belief, attitude, or opinion is said to possess centrality if it lies close to the person's values (Bem 1970). Also according to Bem "labels like liberal and conservative usually enable us to predict many of the individual's attitudes because these two terms refer to broad underlying values which are shared by large segments of the population." Since individuals attempt to maintain consistency with central values and attitudes, this implies a causal flow in the direction of decreasing centrality.

There is evidence that people can be arrayed in terms of the strength of their ecological concern (Maloney. Ward, and Braucht 1975) and that they exhibit consistency between their ecological attitudes and behaviors (Kinnear and Taylor 1974, Antril and Bennett 1979). Although the link between ecological concern and voting behavior has not been established, this seems to be a logical extension of these findings and is the reason for including ECI in the model.

It is clear academically that environmental protection can have serious economic consequences in terms of inflation, slowed GNP growth, reduced investment in productive facilities, and unemployment. It is suspected that members of the general public also see this environment-economic tradeoff to some extent, especially on such concrete matters as unemployment. A variable labeled JOBS was included in the model to represent an influence of economic concern that might run counter to the influence of environmental concern.

The variables ECI and JOBS were positioned at level 3, indicating moderate centrality. These general attitudes and opinions are thought to represent the individual's orientation and affinity for certain social goals which serve to guide preferences and choices in specific situations. As such, these general attitudes may also be indicative of some of the individual's underlying values and motives.

The variables at Level 4, parallel those at level 3, but with greater specificity to the question of the deposit law. Whereas the variable JOBS reflects a macroeconomic concern about environmental protection, COST reflects a microeconomic concern about the deposit law, namely its effect on prices. Likewise, the variable ECI reflects a concern about the environment in its many suspects while LITTER taps only a small part of that, namely concern about beer and soft drink container litter, it is expected that the attitudinal variables at Levels 3 and 4 will be associated. It is assumed that the causal flow is from the more general to the more specific attitudes (from 3 to 4). Finally, it is recognized that other potentially relevant variables dealing with the impact of the deposit law could have been included at level 4 (ac the expense, of course, of greater modal complexity).

The behavioral variables are represented at Level 5 in the model. They include not only the criterion VOTE but also the prior use of returnables (RETURN). Since both of these can be construed as ecological behaviors, an important question is whether they are influenced by the same variables in the same fashion. It is also assumed that the related consumption variable RETURN would causally influence VOTE since consumers are likely to resist changes in their consumption habits for convenience type goods like beverages. A good deal of support for this assertion exists within learning theory as applied to marketing (Howard and Sheth 1969).

PROCEDURE

Data

The data utilized in this study were obtained from a telephone survey of 306 voting age adults in the State of Michigan. Interviews were conducted between October 23-30, 1976 with the last interview obtained three days before the election. Respondents were selected using a random digit dialing method similar to Waksberg's Two-Stage Procedure (Frankel and Frankel 1977). A randomization procedure was used to select from multiple eligible adults within the same household. The calling was done from a central location. The interview lasted about 25 minutes.

Interviews were completed with 61% of those who were contacted and determined to be qualified. The sample matched population estimates in terms of sex and area of residence. Some differences were noted on education, age, and income but not of sufficient magnitude to seriously affect the relationships under investigation. The survey results predicted the election outcome with a high degree of accuracy.

Measures

Both single items and multi-item indices were used to measure the theoretical constructs. Theoretically related items were combined whenever it was possible to form an index having satisfactory reliability for this type of research.

Socioeconomic status (SES) was measured as a three factor index including income, education, and occupation. As was the case for all the indices, each component received an equal weight. Cronbach's Alpha for SES was .48.

The alienation index (ALIEN) measures the extent to which feelings of powerlessness, meaninglessness, and social isolation are experienced by the respondent. High scores on the index indicate more alienation. This basic approach to measuring the construct is generally consistent with other research operationalizations (see: Aberbach 1969; Stone 1965). Cronbach's Alpha for ALIEN was .48.

A single item (LIBER) was used to measure the respondent's political orientation, with special reference to the role of government in economic affairs (i.e., whether government should force all products that pollute off the market). Because a large portion of regulatory activity in the 1970's concerned the environment, this seemed to be a meaningful way to ascertain feelings about government involvement. It is recognized that other dimensions of liberalism-conservatism exist. However, it is also true that the organization of political idea elements begins to breakdown as one moves from more to less sophisticated publics (Converse 1970), suggesting that the attitude domain should be more narrowly defined as was done here.

An ecological concern index (ECI) was formed to measure the respondent's concern about protecting the environment. The starting point for this index was an earlier version of the ECI developed by Kinnear and Taylor (1973), although the current version is strictly attitudinal in nature. Higher ECI scores indicate more concern about the environment. Cronbach's Alpha for this index is .60.

A single item (JOBS) was used to measure the respondent's concern about the macroeconomic impact of environmental protection. The JOBS variable focuses on unemployment which is a concrete manifestation of the economic/environment tradeoff. Higher JOBS scores indicate more concern about the effects of environmental protection on unemployment.

A single item (COST) was used to measure the respondent's concern about a microeconomic impact of the deposit law, namely its effect on beverage prices. Higher COST scores indicate more concern about the adverse price effects of the law.

Concern about the degree to which beverage containers contribute to pollution and litter, an opinion highly specific to the deposit law, was measured by the LITTER index. Higher LITTER scores reflect the respondent's perception that container litter is a major problem. Cronbach's Alpha for this index is .72.

Prior use of returnables (RETURN) was determined by asking respondents whether they usually purchased soft drinks and beer in returnable bottles, non-returnable bottles, or cans. Responses to this question were coded: usually returnables = 1 and usually throwaways = 0.

To measure voting preference regarding the deposit law (VOTE), respondents were exposed to a statement of the law as it would appear on the ballot, and then asked "if the election was held today, would you vote yes or no on the deposit law?" Responses to this question were coded: yes = 1 and no = 0.

ANALYSIS AND RESULTS

The causal model was analyzed by the method of structural equation analysis. Path analysis is a useful method to determine whether the data are consistent with the a priori model. However, consistency of the data with the model does not provide proof of the theory, but only lends support to it (Kerlinger and Pedhazer 1973, p. 307).

The structural equations and path coefficients were estimated by ordinary least squares regression analysis. While this method of analysis assumes all variables are measured on interval scales, multiple regression is still the recommended procedure when ordinal scales are used, as in this study (Bohrnstedt and Carten 1971). Other assumptions underlying the application of path analysis appeared to have been met (see Kerlinger and Pedhazer 1973, p. 309).

Table 1 shows how the a priori models were tested, trimmed, and how the path coefficients were estimated. The a priori models in this study were simply the regression models relating each variable to those variables preceding it in the causal flow of Figure 1. Table 1 shows the regression coefficients in unstandardized and standardized form. The standardized coefficients are referred to as "path coefficients."

Goldberger's (1970) approach to model trimming was used and a significance criterion of p < .05 was set as suggested by Duncan (1975). The trimming involves a reestimation of the regression equations with the predictors found nonsignificant in the first attempt eliminated. The regression and path coefficients for the trimmed models also appear in Table 1. A comparison of the coefficients of determination (R2) for any of the a priori models and trimmed models indicates no significant loss in explanatory power resulting from theory trimming. Figure 2 is a diagram of the trimmed model showing the causal paths found to be significant.

TABLE 1

PATH ANALYSIS RESULTS

FIGURE 2

TRIMMED MODEL

From an analysis of Figure 2, structural equations were developed that could be used to decompose the total association between the variables, Due to the complexity of the model no attempt was made to specify the nature of the noncausal association (i.e., to distinguish between spurious association and unanalyzed correlation). By substituting the path coefficients of the trimmed models appearing in Table 1, into the structural equations, it was possible to decompose the total association between each variable and those that causally precede it. These results are summarized in Table 2. This table shows the decomposition of the total association (i.e., the simple correlation) into direct, indirect, total causal, and noncausal association.

TABLE 2

THE COMPONENTS OF TOTAL ASSOCIATION

The VOTE Model

The test of the VOTE model indicated that RETURN, COST, LITTER, ECI, JOBS, and ALIEN all had significant direct effects on VOTE (p < .01) and, in the trimmed model, accounted for 40% of the variance in VOTE. The valences of the beta coefficients indicated that supporters of the deposit law were more litter conscious, were less concerned about the potential impact on either beverage costs or unemployment, were more ecologically concerned, and were less alienated. Supporters were also more likely to have been previously purchasing returnables.

The magnitudes of the direct effects on VOTE generally decline as the causal variables become more remote. The variables with the largest direct influence on VOTE were assigned either to Level 4 (COST = -.40 and LITTER = .19) or Level 5 (RETURN = .15). Direct effects of less magnitude were obtained for the variables at Level 3 (ECI = .14 and JOBS = -.12), Level 2 (LIBER = N. S.), and Level 1 (SES = N. S. and ALIEN = -.09). These findings are consistent with the nature of the causal flow postulated in the a priori model.

An examination of the components of total association (Table 2) indicates that all predictors had some causal impact on VOTE. Several variables assumed greater prominence when total effects were computed because, they had substantial indirect effects. This was particularly true for ECI which was second highest in terms of total effect (= .32). This finding provides additional support for the consistency of ecological attitudes end behaviors. Two of the variables that lacked significant direct effects were found to have notable indirect effects. This was the case for LIBER (= .12) and SES (= .07). The negative total association between VOTE and ALLEN (= -.14) supports the "alienated voter hypotheses."

Other Important Findings

Few of the variables appeared to exert much influence on the voluntary use of returnable containers (RETURN) and only 4.4% of the variance in RETURN vas accounted for by the trimmed model. The total causal effect of ECI on RETURN (= .04) was much less than on VOTE (= .32). Apparently, returnables were being purchased for reasons other than ecological concern (e.g., habit, brand loyalty, etc.).

Contrary to the model, concern about the price effects of the law (COST) was unrelated to concern about the potential effects of environmental protection on unemployment. Instead, the general attitude of ECI was found to have a relatively strong direct influence on both of the specific attitudes: COST (= -.20) and LITTER (= .47). As might be expected, concern about the effects of the deposit law on prices was greater among alienated consumers and those of lower SES.

The general attitude of ECI was found to be related to LIBER and SES. As hypothesized by Mayer (1976), ecologically concerned consumers appeared to be more liberal. As he suggests, holding these opinions may offer the liberal a chance to express his or her progressive and humanitarian values. Ecological concern can be viewed as a relatively central attitude mediating these values.

A positive direct effect (= .14) vas found to link SES to ECI. At the sane tine, however, those with higher SES scores tended to be more conservative. Greater conservatism implies less ecological concern. The total association linking SES to ECI was reduced (to .07) as the result of this countervailing tendencies. As expected, consumers of lover socioeconomic status were more alienated.

INTERPRETATION

It should be re-emphasized that path analysis is not capable of proving causality but serves mainly to identify the logical consequences of the causal assumptions that are made. While the data in this study were generally consistent with the model, consistency itself does not establish causality. The data may also be consistent with other models not considered. Path analysis vas found to be useful, however, in uncovering associations that would have been overlooked using conventional methods.

The substantive findings indicate that consumers perceived voting for the deposit law as a rather clear expression of their ecological concern. This points to a successful marketing effort on the part of the environmentalists. Prior to the election, however, consumers did not seem to associate buying returnables with ecological concern. Either that, or returnables were found to be unacceptable for some other reason (e.g., non-availability of favorite brands). This suggests that Ecological Marketing efforts by industry to sell returnables were either ineffective or non-existent prior to the election.

The success of the deposit law indicates there is sufficient ecological concern among the population to undertake Ecological Marketing programs. However, in marketing the "bottle bill" to Michigan consumers environmentalists did not rely solely on its ecological appeal. As part of their strategy, they successfully attached support of the law with the specific benefit of reducing litter. Also, they successfully overcame consumers' concern about the adverse effects of the law on prices and the economy.

CONCLUSION

Through the method of path analysis additional insight can be gained into the motivational basis of ecological behavior. The technique offers several advantages and should be used in future research dealing with the ecologically concerned consumer. One important advantage is that it forces researchers to make explicit their causal assumptions. A causal model employing demographic, psychological, and behavioral variables seems to have application to the study of the ECC. With additional elaboration, refinement, and testing a general model of ecological consumption behavior might be developed.

REFERENCES

Aberbach, Joel D. (1969), "Alienation and Political Behavior," American Political Science Review, 63, 86-99.

Adorns, T. W., Frenkel-Brunswik, E., Levinson, D. J., and Stanford, R. N. (1950), The Authoritarian Personality, New York: Harper.

Anderson, W. Thomas Jr., and Cunningham, William H. (1972), "The Socially Conscious Consumer," Journal of Marketing, 36, 23-31.

Anderson, W. Thomas Jr., Henion, Karl E., and Cox, Eli P. III (1974), "Socially vs. Ecologically Responsible Consumers," American Marketing Association Conference Proceedings.

Antril, John H. and Bennett, Peter D. (1979), "Construction and Validation of a Scale to Measure Socially Responsible Consumption Behavior," in The Conserver Society, ed. Karl E. Henion and Thomas C. Kinnear, Chicago: American Marketing Association, 51-68.

Arndt, Johan and Helgesen, Thorolf (1979), "Marketing of Ecologically Compatible Products: Public Policy Issues and a Market Test," in 1979 Educators' Conference Proceedings, ed. Neil Beckwith et. al., Chicago: American Marketing Association, 594-597.

Bem, Daryl J. (1970), Beliefs, Attitudes, and Human Affairs, Belmont, California: Brooke/Cole Publishing Company.

Bohrnstedt, G. W. and Carten, T. M. (1971), "Robustness in Regression Analysis" in Sociological Methodology 1971, H. L. Costner, ed. San Francisco: Jossey-Bass, 118-46.

Buttel, Frederick H., and Flinn, William L. (1976), "Environmental Politics: The Structuring of Partisan and Ideological Cleavages in Mass Environmental Attitudes, Sociological Quarterly.

Constantini, Edmond, and Hanf, Kenneth (1972), "Environmental Concern and Lake Tahoe: A Study of Elite Perceptions, Backgrounds, and Attitudes," Environment and Behavior, 4, 209-2&2.

Converse, Philip E. (1970), "The Nature of Belief Systems in Mass Publics," in William J. Crotty, ed., Public Opinion and Politics, New York: Holt, Rinehart, and Winston, pp. 129-155.

Duncan, Otis Dudley (1975), Introduction to Structural Equation Models, New York: Academic Press.

Dunlap, Riley E. (1975), "The Impact of Political Orientation on Environmental Attitudes and Actions," Environment and Behavior, 7, 428-454.

Frankel, Martin R., and Frankel, Lester R. (1977), "Some Recent Developments in Sampling Design," Journal of Marketing Research, 24, 280-93.

Goldberger, A. S. (1970), "On Boudon's Method of Linear Causal Analysis" American Sociological Review, 35, 97-101.

Henion, Karl E., and Wilson. William R. (1976), "The Ecologically Concerned Consumer and Locus of Control," in Ecological Marketing, ed. Karl E. Henion and Thomas C. Kinnear, Chicago: American Marketing Association.

Henion, Karl E. (1976), Ecological Marketing, Columbus, Ohio: Grid, Inc.

Horton, John E. and Thompson, Wayne E. (1962), "Powerlessness and Political Negativism: A Study of Defeated Local Referendums," American Journal of Sociology, 67, 485-494.

Howard, John A. and Sheth, Jagdish N. (1969), The Theory of Buyer Behavior, New York: Wiley.

Kassarjian, Harold H. (1971), "Personality and Consumer Behavior," Journal of Marketing Research, 8, 409-18.

Katz, D. (1960), "The Functional Approach to the Study of Attitudes," Public Opinion Quarterly, 24, 163-204.

Kerlinger, Fred N., and Pedhazur, Elazar J. (1973), Multiple Regression in Behavioral Research, New York: Holt, Rinehart, and Winston, Inc.

Kinnear, Thomas C., and Taylor, James R. (1973), "The Effect of Ecological Concern on Brand Perceptions," Journal of Marketing Research, 10, 191-198.

Kinnear, Thomas C., and Taylor, James R. (1974), "Identifying Ecological Buying Segments Through Attitude Measurement," Journal of Business Administration, 3, 33-43.

Kinnear, Thomas C., Taylor, James R., and Ahmed, Sadrudin A. (1974), "Ecologically Concerned Consumers: Who Are They?" Journal of Marketing, 38, 20-24.

Koenig, D. J. (1975), "Additional Research on Environmental Activism," Environment and Behavior, 7, 472-485.

Lepisto, Lawrence R. (1979), "Environmental Product Attributes and Product Preference," in Proceedings, ed. Robert M. Hopkins, and Alfred G. Toms, Lafayette, Louisiana: Southern Marketing Association.

Maloney, Michael P., and Braucht, G. Nicholas (1975), "A Revised Scale for the Measurement of Ecological Attitudes and Knowledge," American Psychologist, 787-90.

Mayer, Robert N. (1976), "The Socially Conscious Consumer-Another Look at the Data," Journal of Consumer Research, 3, 113-115.

Murphy, Patrick E. (1978), "Environmentally Concerned Consumers: Demographic Dimensions," in Proceedings of the 1978 Educators' Conference, ed. Subhash C. Jain, Chicago: American Marketing Association.

Murphy, Patrick E., Kangun, Norman, and Locander, William B. (1978), "Environmentally Concerned Consumers -- Racial Variations," Journal of Marketing, 42, 61-66.

Nelson, James E. (1974), "An Empirical Investigation of the Nature and Incidence of Ecologically Responsible Consumption of Housewives," Unpublished doctoral dissertation, University of Minnesota.

Stone, Clarence N. (1965), "Local Referendums: An Alternative to the Alienated-Voter Modal," Public Opinion Quarterly, 29, 199-222.

Tognacci, Louis N. (1972), "Environmental Quality: How Universal is Public Concern?" Environment and Behavior, 4, 73-86.

Webster, Frederick E., Jr. (1975), "Determining the Characteristics of the Socially Conscious Consumer," Journal of Consumer Research, 2, 188-196.

----------------------------------------