The Role of Interpersonal Sources in External Search: an Informational Perspective

Linda L. Price, University of Pittsburgh
Lawrence F. Feick, University of Pittsburgh
ABSTRACT - Previous research on external search has provided little insight into the ways in which interpersonal sources are used in making consumer choices. The purpose of this paper is to explore the use of interpersonal sources in external search. After the literature on social influence is reviewed, the paper reports the results of an exploratory study of interpersonal information seeking. The results indicate the use of interpersonal sources of information is widespread and suggest there is an extensive number of roles played by interpersonal sources in the decision process. In addition, the results support the existence of informational motives for social comparison.
[ to cite ]:
Linda L. Price and Lawrence F. Feick (1984) ,"The Role of Interpersonal Sources in External Search: an Informational Perspective", in NA - Advances in Consumer Research Volume 11, eds. Thomas C. Kinnear, Provo, UT : Association for Consumer Research, Pages: 250-255.

Advances in Consumer Research Volume 11, 1984      Pages 250-255

THE ROLE OF INTERPERSONAL SOURCES IN EXTERNAL SEARCH: AN INFORMATIONAL PERSPECTIVE

Linda L. Price, University of Pittsburgh

Lawrence F. Feick, University of Pittsburgh

ABSTRACT -

Previous research on external search has provided little insight into the ways in which interpersonal sources are used in making consumer choices. The purpose of this paper is to explore the use of interpersonal sources in external search. After the literature on social influence is reviewed, the paper reports the results of an exploratory study of interpersonal information seeking. The results indicate the use of interpersonal sources of information is widespread and suggest there is an extensive number of roles played by interpersonal sources in the decision process. In addition, the results support the existence of informational motives for social comparison.

INTRODUCTION

Consumer researchers have recently made important contributions to the study of information processing (Bettman and Kakkar 1977, Bettman 1979, Sheluga, Jaccard and Jacoby 1979, Ratchford 1982). Several of the efforts have focused on describing the extent and type of external search (Claxton, Fry and Portis 1974, Kiel and Layton 1981, Westbrook and Fornell 1979, Newman and Lockeman 1975). In general, the studies have shown that consumers engage in limited external search, often restricting their effort to a single alternative or a single source of information (Newman and Staelin 1972, Newman 1977, Olshavsky and Granbois 1979). Studies have also generally indicated that interpersonal sources were named more frequently than other sources (Riel and Layton 1981, Katona and Mueller 1955, Udell 1966, Thorelli 1971). The findings also suggest that buyers have distinctive patterns of source usage, with some preferring certain kinds of sources and others consulting a wider variety of sources (Claxton, Fry and Portis 1974, Newman and Staelin 1972, Westbrook and Fornell 1979).

Previous research on external search has tended to focus on identifying general patterns of source usage. The descriptive nature of these studies has left largely unanswered the question of why consumers reflect certain patterns of source usage. In particular, the studies have provided little insight into the reasons consumers prefer interpersonal sources of information, or ways in which interpersonal sources are accessed and used in making consumer choices.

The purpose of this paper is to explore the use of interpersonal sources in external search. Specifically, the paper identifies three unresolved issues which are central to understanding the use of interpersonal sources in external search. These issues are: (1) the importance of expertise in the choice of interpersonal sources; (2) the extent to which interpersonal information seeking can be generalized across product types; and (3) the diversity of roles interpersonal sources play in the decision process.

The exploratory research reported in this paper focuses on one general class of interpersonal sources--knowledgeable friends, relatives or acquaintances. The findings of this research illustrate how pervasive the use of this type of source is in contrast to both other types of interpersonal sources (such as conversations with salespeople or professionals to whom a fee is paid), and no interpersonal sources of information. The results also provide some insights into the resolution of the three issues identified above.

The state of extant literature and findings of this research emphasize the need for a broader theory of interpersonal source usage. Such a theory must address both the elements of social comparison theory and the costs and benefits of external search. The paper suggests research directions consistent with the construction of a broader theoretical framework

BACKGROUND

Festinger (1954) introduced social comparison theory, postulating that in the absence of objective reality checks a person will use others as points of reference. Fundamental to social comparison theory is the impact of reference groups on attitude formation and attitude change. While there is no one accepted definition of a reference group, it is generally taken to include a group to which an individual belongs, aspires to belong, or aspires not to belong (Stafford 1966). Despite consumer researchers' acknowledgement that reference group influence is an important antecedent of product choice (e.g., Zaltman and Wallendorf 1983) the relationship has received only cursory examination by consumer researchers (Becherer, Morgan and Richard 1969, Olshavsky and Granbois 1979, Midgley 1983). In addition, the extent to which interpersonal influence falls outside the accepted understanding of reference groups has not been explored within a social comparison framework.

Nevertheless, research from a variety of areas can be interpreted as supporting the pervasiveness of social influence and the significance of social influence, even when pressure to comply with norms is at a minimum. For example, Menzel and Katz (1955), in a now classic study, demonstrated that physicians learned of innovations in drugs not from reputable medical journals or respected colleagues, but from drug salesmen. Research by Feldman and Spencer (1965) revealed that 75 percent of newcomers to a community used a recommendation as the r sole basis for selection of a physician. In experimental research, Cohen and Golden (1972) found that even for a familiar product in which taste was the sole criterion for evaluation, individual Judgments were modified by the perceived evaluations of others. This modification in judgment occurred despite the fact that no attempt was made to encourage subjects to believe that the information conveyed by others was accurate or reliable. These findings particularly call into question the restrictive notion of reference groups and the narrow class of motivations previously thought to moderate the influence of others in consumer choice

With few exceptions, research on consumer behavior on social influence has focused on normative social influence: "influence to conform with certain expectations held by others" (Cohen and Go]den 1972, p. 54). However, research suggests that motivations for using interpersonal sources of information are more complex. An equally, if not more important type of social influence may be informational social influence: "influence to accept information provided by others which is taken as evidence about reality" (Cohen and Golden 1972, p. 54). Consumer researchers have generally failed to distinguish normative social influence from informational social influence.

The distinction is an important, but subtle one. Normative social influence is tied to the idea of conformity, i.e., one accepts influence because of the desire to identify with certain individuals or their points of view. Informational social influence, however, is not true conformity. It is motivated not solely by the desire to behave in a socially correct or appropriate way, but by the complexity of product evaluation and the problems of resolving informational uncertainties. In the next three sections, literature on the influence of referents is discussed in light of informational and normative motivations for social comparison. The argument is made that informational motivations may be stronger than normative motives in the case of certain products, situations and decision characteristics. In addition, the basis for choosing a referent may vary depending on whether the motivation is informational or normative.

Referent Expertise

A central unresolved issue in social comparison theory is the role of expertise in an individual ' s selection of a referent. Research results conflict, with some work finding referent expertise to be an important predictor of influence (e.g., Witt and Bruce 1972, Fazio 1979, DeCarufel and Insko 1979), and others finding different factors to be more important (e.g., Cohen and Golden 1972, Mochias 1972, O'Reilly 1982). Two issues are relevant in assessing the role of expertise in the selection of a referent: (1) To what extent does an individual select someone with similar as opposed to greater knowledge; and (2) To what extent does an individual select someone who is accessible as opposed to knowledgeable. These issues are closely related since if an individual selects a referent who is similar to him/herself it may be simply because such individuals tend to be more accessible.

Co-orientation or Expertise

The first issue noted above is whether or not the individual selects a referent similar to him/herself. The theory of co-orientation posits an individual is more likely to compare oneself to an individual (or group) at about the same level on given attributes than with an individual who is either greatly superior to or greatly inferior to oneself (Jones and Gerard 1967). Some research supports the co-orientation model. These studies have found that interpersonal-communication dyads tend to be fairly homogenous on various attributes (Mochias 1976, Brock 1965, Chaffee and McLeod 1973, Clarke 1971). Other studies, however provide conflicting results. For example, Cocanougher and Bruce (1971) demonstrate the importance of socially distant reference groups--reference groups with whom the recipient does not have regular interaction. Fazio (1979) provides evidence that under certain conditions individuals will choose as their preferred referent someone they believe is more of an expert than they are. Fazio (1979) hypothesize, that in the case of important decisions for which individuals need information, preference for a referent will vary as a function of the perceived level of information possessed by the referent. DeCarufel and Insko (1979) have found empirical support for this hypothesis. However, under other circumstances, self-esteem maintenance may become primary and the individual may be unwilling to risk informational social comparison (Fazio 1979, DeCarufel and Insko 1979). Finally, some studies have found considerable variance in the degree of reference group homogeneity with respect to the object of orientation, both as a function of the nature of the product and certain personality characteristics of the members (Witt and Bruce 1970, Clarke 1973).

Several possible explanations could be advanced for employing someone similar to oneself as a referent. One explanation is that such individuals may be perceived as having more expertise. This could occur, for example, if individuals with similar values are seen as being easier to communicate with or perceived as having more relevant input to the decision problem the consumer faces. The reasons are consistent with an informational motivation for social comparison. [Empirically, some work has defined co-orientation as having encountered a similar consumption problem (e.g., Brock 1965). This approach seems to confound expertise with co-orientation, perhaps because the work has not drawn the distinction between informational and normative social influence.] On the other hand, self-esteem maintenance and social conformity may be more consistent with normative motivations for social comparison. However, of the possible explanations for employing someone similar to oneself as a referent, one of the most important appears to be that such individuals are more accessible.

Expertise or Accessibility

Some research suggests that access to someone else's views may be more important than the perceived quality or expertness of the view. For example, O'Reilly (1982), in a study of organizational decision-maker's use of information sources, found that frequency of use of these sources was primarily a function of their ease of access. However, because the group (the primary interpersonal source of information) was highly accessible to the members, its influence was not predicted by ease of access. Also, perceived quality of the information available was found to be related to the rated importance of the information source in the final decision. Overall, the issue of how access affects the use of interpersonal sources remains unresolved. Most studies provide no explicit treatment of the accessibility of sources, or tend to confound expertness and availability (e.g., Stafford 1966, Witt and Bruce 1972).

A common belief in the literature on social influence in product diffusion is that influence grows out of the natural interaction of the group members (Rogers 1983). Research has not examined the extent to which a knowledgeable individual is actively sought to assist in selecting a product, except for the extensive research on the use of salespeople (e.g., Claxton, Frey and Portis 1974). Implied in much of the research on the use of interpersonal sources for information seeking is the belief that the prevalence of the use of these sources is motivated by easy access and naturally occurring social interaction (Reynolds and Darden 1971, Wackman 1973). While, clearly, the exchange of product information during natural interpersonal interaction is an important source of social influence, research based on this assumption may be underestimating the advantages of interpersonal information vis a vis other sources.

Product Characteristics

Much of the research on social influence has attempted to demonstrate differences in group influence on product choice based on social involvement in the product. The studies have covered a wide range of product complexity and price (from beer, cigarettes and cologne to women's fashions and men's suits). While some of these studies have demonstrated differences in group influence (Witt and Bruce 1970),others have not (Becherer, Morgan and Richard 1979). The research contrasting social influence across product classes has typically begun with the assumption that social influence is normatively motivated. This has lead to contrasts between products high in social or ego involvement and products low in social or ego involvement. Such comparisons are revealing but may tend to understate informational motivations for social comparison. Since the emphasis on expertise as opposed to co-orientation is more important in the case of product decisions with greater relative risk, research on major consumer durables may be useful in assessing the impact of informational rather than normative motives for interpersonal information seeking.

Role of Influencer

Related to the discussion above is the issue of how interpersonal sources are used in the decision process. Past research has stopped short of examining the nature of the influence from interpersonal sources. Emphasis has been on questions such as "did you talk with friends before purchasing this product" or "how important were friends in your choice of this product." In the case of products high in social or ego involvement (such as men's suits) social influence may operate primarily to provide a frame of reference or a standard against which to evaluate products (Venkatesan 1966, Midgley 1983). However, it may be that interpersonal sources accessed for informational social comparison reasons are employed in a number of different ways during the external search process (in much the same way as are other external sources of information). For example, the consumer may be concerned with simply collecting information about the product (or information about where to get information about the product), or the individual may want to know whether available information has been processed and integrated appropriately. Part of the development of a broader theory of the use of interpersonal sources is understanding whether interpersonal influence is dominant in one part of the decision task or whether influence is spread over different facets of the external search process.

Summary

The previous three sections identified some unresolved issues in the use of interpersonal sources. The thrust of each section was that informational components of social comparison have been neglected in studies of interpersonal source usage. The exploratory research reported below was undertaken with the limited objective of demonstrating the prevalence of use of interpersonal sources relative to other sources of information across a range of consumer durables, and to provide preliminary evidence of the informational motivations behind the use of knowledgeable friends, relatives and acquaintances.

METHOD

In order to gain insight into the use of expert judgment by consumers, a convenience sample of 86 undergraduate business students at a large northeastern university were surveyed. All of these students were taking their first course in marketing. The questionnaire was administered prior to any course discussion of information search or consumer behavior in order to minimize bias in support of researchers' implicit hypothesis. While with a sample of this type, demographic characteristics were not representative of the general population of consumers, the sample was considered adequate to provide a guide to future research. In fact, these respondents may offer somewhat greater diversity than other student samples. For example, about 30% were attending night school while pursuing full-time careers, 10% of the respondents were over 35 years of age, and about 30% of the respondents were married.

Respondents were asked to think of a high priced (over $75), many featured, long-lived product which they expected to purchase in the coming six months. Respondents were then asked a number of questions about the purchase of this product. A unique feature of this research is that it began with an open-ended question asking respondents to describe the first step they would take in deciding which alternative to buy. Other items included questions on familiarity with the product type, interest in reading and talking about the product type, information sources expected to be used prior to purchase, and the accessibility and potential uses of knowledgeable friends, relatives and acquaintances.

RESULTS

Product Mentioned

Respondents reported considering a wide range of types of products for their purchase. About 47 percent of the respondents listed some type of electronic equipment (personal computer, camera, stereo, video-recorder, etc.), and another 29 percent were interested in purchasing a car. However, the range of products also include. a rototiller, a leather jacket, and carpeting. Past studies have tended to focus on a single product class and have offered insights into the type and use of information within the class. An advantage of the present research is in suggesting the generalizability of interpersonal source usage across a broad array of product types. The data contained too few observations in some product classes to make meaningful comparisons. However, no significant differences in the use of interpersonal sources were found, for example, between respondents listing some type of electronic equipment and those interested in purchasing a car.

Use of Experts

In response to the open-ended question, eighty-one percent of the respondents reported search from an external source as the first step they would take in deciding which alternative to buy. Of those who mentioned an external source, 49 percent reported they would seek information from a knowledgeable friend, relative, or acquaintance. Additionally, 41 percent reported they would seek information from some other interpersonal source (such as a salesperson).

In a later, structured question, respondents reported on Likert-type scale how likely they were to use each of a variety of information sources. About 91 percent of the respondents reported they were very likely or somewhat likely to use knowledgeable friends, relatives, or acquaintances as sources of information in the product purchase. Table l presents means for the likelihood of usage of the sources based on a five point scale (1 = not likely, 5 = very likely). An examination of the means for these items reveals that the anticipated use of experts as a source was significantly greater than the use of any other source.

TABLE 1

PROSPECTIVE MEAN USAGE OF VARIOUS EXTERNAL INFORMATION SOURCES

While, as might be expected, a large number of the respondents who anticipate using an expert have a person in mind who they can easily contact, a substantial number of individuals report not knowing who they will contact or that the expert they intend to contact is relatively inaccessible. Again, examining just the 91 percent of the respondents who were somewhat or very likely to use an expert, about 23 percent reported they were uncertain about the availability and/or accessibility of such a knowledgeable individual

Role of Experts in the Decision Process

In order to explore the range of ways experts would be used by consumers in making purchase decisions, respondents who were somewhat or very likely to use an expert (i.e., n= 78 or 91% of total sample) were questioned about several of the possible roles the knowledgeable individual could play in the decision-making process. Table 2 reports the percentage of respondents who were somewhat or very likely to use a knowledgeable friend, relative or acquaintance in each of the roles. Broadly, the roles include structuring the decision problem (e.g., uses 1,2,3), providing information to the consumer (e.g., uses 6,7,8,9), validating the respondent's decision process (e.g. 4,10), and aiding in evaluating or evaluating product alternatives (e.g., 5,11, 12).

As indicated, with the exception of using the expert to actually make the decision (use 12), a majority of the respondents felt they would be likely to use the expert in each of the possible ways. While these results strongly support the pervasiveness of the use of knowledgeable o.hers, it is possible that the phrasing of the questions or the context could have encouraged a positive response.

TABLE 2

PERCENTAGE OF RESPONDENTS WHO WERE SOMEWHAT OR VERY LIKELY TO USE A KNOWLEDGEABLE INDIVIDUAL IN THE MANNER DESCRIBED

DISCUSSION

The ideas addressed in this research may seem quite intuitive. Each of us has probably had occasion to employ someone else's expertise in a product category rather than read a variety of material or scan a vast array of product alternatives ourselves. It seems clear that a knowledgeable friend, relative, or acquaintance is more capable of being a provider of impartial, current, digested and interpretable information than any other single source. Particularly in cases where the costs of a poor decision are high and search costs are also high (because of the complexity of the product, uncertainty about availability or prices, etc.), the incentive to use the Judgment of a knowledgeable interpersonal source is substantial. Yet, previous research has tended to underplay the informational motivations for interpersonal influence.

Consistent with previous work, the present research has found that interpersonal sources of information are more likely to be used than other types of sources. The importance of interpersonal sources was confirmed using an open-ended question designed to alleviate the reporting biases of structured items on information source usage. In addition, the results of this research have provided insight into three substantive issues previously under-researched.

First, the results indicated a substantial number of individuals who were quite likely to use experts did not have a good idea of how they would contact an expert or what person they would contact. This result suggests that access is not the sole determinant of interpersonal information seeking. At least some consumers appear to seek out referents for interpersonal information about product decisions. In addition, this result offers some support for the distinction between normative and informational social influence. As noted previously, the use of accessible sources does not necessarily imply the operation of normative rather than informational social influence. Use of accessible sources can be seen as very consistent with informational motives (i.e., improving communication, lowering the costs of search, etc.). However, the intended use of inaccessible sources or sources unknown to the respondent makes an even stronger case for the informational motives of social influence. It's hard to argue that these experts are members of the individual's reference group or that they are accessed to provide the individual with norms for behavior. While data from the current research to not allow formal testing of informational and normative influence as rival motivational hypotheses, the data suggest informational social influence deserves more consideration than it has received previously in consumer research.

Second, although consumer research in social influence has typically focused on products high in social or ego involvement, this research has demonstrated the applicability of social influence in the choice of products with a large functional component, e.g., electronic equipment and cars. This result illustrates that the notion of social influence has been unnecessarily constrained to a narrow domain of consumer choices. This narrow view of social influence may account for the lack of research into the determinants of interpersonal information seeking and the tendency to dismiss such search as trivial

Third, the present research has illustrated that the role of the referent in information provision can be quite varied . It seems quite significant that 15% of the consumers reported they would actually be likely to let an interpersonal information source choose the product for them. The variety of other ways in which an expert might be used helps to substantiate the importance of interpersonal sources for both constructing a view of reality and validating an existing view. For example, over 80% of the respondents indicated they would be likely to use a knowledgeable other to help identify salient features of the product given the respondent's needs (i.e., constructing reality). Validation of an existing view is also apparent as about 70 percent of the respondents indicated they would use a knowledgeable other to confirm the reasonableness of their decision making approach.

RESEARCH DIRECTIONS

It seems ironic that what may be consumers' most important source of information has been largely ignored in consumer research. Perhaps because the phenomenon has been viewed-simplistically it has been treated simplistically. In any case, researchers have little understanding of the motivations for and dimensions of interpersonal influence. Of the many important consequences of ignoring interpersonal information exchange, two seem crucial. First, ignoring interpersonal information seeking results in an absolute underestimation of the extent of consumer external search. This underestimate may make consumers' decisions seem less rational or more affectively motivated than they actually are. Second, ignoring interpersonal information seeking leads to an overestimate of the relative importance of noninterpersonal sources. These sources may actually play a much smaller relative role in decision making than would be assumed when interpersonal sources are not considered.

These consequences have obvious policy implications. Policy prescriptions based on an erroneous set of assumptions about the extent and composition of external search are themselves likely to be flawed. Clearly, a theoretical framework which includes interpersonal influence as a nontrivial component of external search is required. In developing this framework, a number of research areas appear to he of highest priority. These include:

(1) An assessment of the relative roles of co-orientation and expertise in determining the selection of an expert. Particular attention needs to be paid to conceptually and empirically distinguishing these two. The distinction is not likely to be clear-cut. For example, someone who shares similar tastes and values may also be seen as having more expertise in meeting the consumer's special needs. Moreover, the relative importance of co-orientation and expertise are likely to vary be product class (i.e., social and ego-involving versus functional), and by the expert's role in the decision process (i.e., validating the consumer's decision process versus structuring the decision and providing information).

(2) An assessment of the relative roles of accessibility and expertise in determining expert selection. Again, these terms must be meaningfully distinguished. This might involve, for example, controlling for availability of the source and then examining relative preference for nonpersonal sources, co-oriented sources and expert sources. In addition, there exists a need for research on the extent to which interpersonal information exchanges occur passively or are an active part of consumer search.

(3) An assessment of the factors affecting (a) the complemantarity and/or substitutability of interpersonal sources for noninterpersonal sources, and (b) the role the interpersonal sources plays in decision process. In part, the use of an interpersonal source allows the consumer to relegate part of the acquisition and processing of decision information to someone else. The incentive to do this would be likely to depend on characteristics of the consumer (i.e., prior familiarity, involvement), characteristics of the product (i.e., risk, frequency of purchase, trialability, complexity), and characteristics of information sources (i.e., quality, availability). For example, interpersonal sources may be relied on more extensively in cases where a consumer with little prior knowledge is making a risky, infrequent decision. Under these conditions there max be few benefits to collecting information which might not be useful in other decisions.

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