Source-Contact Cue Influence on Attitude Formation and Attitude Persistence

Xiang Fang, University of Kansas
Dennis L. Rosen, University of Kansas
ABSTRACT - This article examines the impact of two source-contact cues (URLs and toll-free numbers) on the attitude formation and attitude persistence. Results from this study are partially supportive of our hypotheses and suggest that, under both high- and low-involvement conditions, subjects have more positive attitude when a URL is included in the ads than when neither cue is present. Consistent with our prediction, under low-involvement conditions, the more related the source-contact cue to a product, the more persistent the brand attitude. Under high-involvement conditions, both cues generate persistent brand attitude regardless of cue relatedness to different product categories. The theoretical and managerial implications are discussed.
[ to cite ]:
Xiang Fang and Dennis L. Rosen (2000) ,"Source-Contact Cue Influence on Attitude Formation and Attitude Persistence", in NA - Advances in Consumer Research Volume 27, eds. Stephen J. Hoch and Robert J. Meyer, Provo, UT : Association for Consumer Research, Pages: 196-201.

Advances in Consumer Research Volume 27, 2000      Pages 196-201

SOURCE-CONTACT CUE INFLUENCE ON ATTITUDE FORMATION AND ATTITUDE PERSISTENCE

Xiang Fang, University of Kansas

Dennis L. Rosen, University of Kansas

ABSTRACT -

This article examines the impact of two source-contact cues (URLs and toll-free numbers) on the attitude formation and attitude persistence. Results from this study are partially supportive of our hypotheses and suggest that, under both high- and low-involvement conditions, subjects have more positive attitude when a URL is included in the ads than when neither cue is present. Consistent with our prediction, under low-involvement conditions, the more related the source-contact cue to a product, the more persistent the brand attitude. Under high-involvement conditions, both cues generate persistent brand attitude regardless of cue relatedness to different product categories. The theoretical and managerial implications are discussed.

INTRODUCTION

Over the years, business firms have provided a variety of was for customers to make contact to gain additional information about products and services or to provide feedback. Toll-free numbers, which have been widely used for many years, are perhaps the most familiar means. In recent years, advertisers have begun to include their Web address or "URL" (Uniform Resource Locator) in their letterhead, business cards, brochures, and print and broadcast advertising (Berthon, Pitt, and Watson 1996).

Some research has found that including toll-free numbers or URLs in traditional media not only increases sales but also enhances company image (Industrial Marketing 1978; Le Forestier 1993; Maddox, Darchan, and Hugh 1997). Thus, toll-free numbers or URLs may act as a "source-contact cue" with implications for attitude toward the ad and the advertiser. In this article, we will illustrate how attitudes toward the brand, advertiser, and advertisement of different product categories are affected by these two source-contact cues under high- and low-involvement conditions.

THEORETICAL BACKGROUND

Elaboration Likelihood Model (ELM)

The elaboration likelihood model (ELM) has been used as a conceptual base for many studies of attitude change (Petty and Cacioppo 1983, 1986). According to this model, there are two distinct routes to persuasion. Under the high-involvement condition, the central route is used with the person thoughtfully considering the issue-relevant information. Under the low-involvement condition, the peripheral route is used. The person does not examine the issue-relevant information very carefully but instead associates the message with simple cues to form an attitudinal judgment. Thus the effect of source-contact cues may vary depending upon involvement. To understand how their effect may vary we must first clarify whether URLs and toll-free numbers in ads are issue-relevant arguments or peripheral cues.

Source-Contact Cues and the ELM

While the presence of a URL or toll-free number by itself does not provide any hard data, both cues have been found to impact perceptions of the firm. Many studies have addressed the impact of toll-free numbers in advertising on consumers’ responses (Industrial Marketing 1978; Le Forestier 1993). These studies have found that using toll-free numbers in advertising not only increases sales significantly but also improves customer satisfaction and enhances corporate image. Recently, the presence of URLs in advertising has attracted the attention of both academics and practitioners. Maddox et al. (1997) found that advertisers displaying URLs were perceived as more customer-oriented, responsive, informative, high tech, sophisticated, and more likely to stay in business longer than those without URLs.

Mackenzie and Lutz (1989) suggest that perceptions of the advertiser have direct impact on attitude toward the advertiser, which follows peripheral processing. Since their simple presence impacts perceptions of the advertiser, we argue that source-contact cues such as URLs and toll-free numbers are peripheral cues, similar to the presence of a celebrity (Petty and Cacioppo 1983), pictures (Miniard et al. 1991), or background music (Park and Young 1986).

HYPOTHESES

Initial Attitude Formation

As previously noted, the source-contact cue, as a peripheral cue, can help project a favorable corporate image, provide ways to communicate with consumers, and potentially increase sales through these communications. Thus, it is reasonable to assume tht ads with source-contact cues will generate more positive attitudes toward the advertiser and advertisement than will ads without these peripheral cues. In addition, according to the ELM, under low-involvement conditions, attitude toward the ad can play a dominant role in brand attitude formation (Park and Young 1986). Therefore, source-contact cues may also have positive effect on brand attitude formation under low-involvement conditions.

H1a: Under low-involvement conditions, ads with source-contact cues will induce more positive attitudes toward the advertiser, advertisement, and brand than will ads without such cues.

While both URLs and toll-free numbers represent methods through which the customer can contact the organization for information and possibly to provide feedback, the impression that each provides concerning the organization may differ. Toll-free numbers have been widely used in a variety of product ads for many years. URLs are more recently appearing cues and as such are more novel than toll-free numbers. According to some research on novelty effects (Sawyer 1981), two factors mediate ad responses. During initial exposures, a novel stimulus may cause uncertainty and tension. Repeated exposure will reduce this uncertainty, leading to positive affect (e.g., familiarity and liking). This process is called habituation. Next, the process of tedium occurs when the repeated exposure to the same stimulus leads to growing boredom and decreased liking.

Generally, habituation plays a major role on ad responses early on and tedium dominates later. The combination of these two processes produces an inverted-U relationship between number of exposures and attitude. Therefore, it is reasonable to assume that the novelty of URLs should make them a stronger peripheral cue with greater affect on attitude than toll-free numbers, at least at the current time.

H1b: Under low-involvement conditions, ads with URLs as the source-contact cue will generate more positive attitudes toward the advertiser, advertisement, and brand than will ads with toll-free numbers.

Under high-involvement conditions, people pay more attention to product-related information, and thus neither peripheral cue should have much effect.

H2: Under high-involvement conditions, presence of source-contact cues in ads will have no impact on initial attitude formation.

Cue Relatedness and Attitude Persistence

The link that exists between a peripheral cue and the product is very important. Sengupta, Goodstein, and Boninger (1997) referred to this as "cue relatedness." Although there are different terms in the literature to describe "cue relatedness" such as fit, relevance and appropriateness (Miniard et al. 1991; Park, Milberg, and Lawson 1991), all lead to stronger memory links between a peripheral cue and an object.

Since a URL is associated with the Internet, it should be more cue-related to those products commonly associated with the Web. Kassaye (1997) introduced the concept of "product fit" or the degree to which a product matches the unique features of the Web. We will refer to this as "Web fit." Generally, the Web is well suited for products or services that require large amounts of information (or time sensitive information) and /or digital trial (Gupta and Chatterjee 1997). Therefore, computer hardware, software, magazines, financial services, and travel agencies ould be examples of products and services with high Web fit for which a URL would have high cue relatedness. Toothpaste, detergent, soft drinks, and snacks would be low-Web-fit products. To leverage this new technology and new medium, companies selling high-Web-fit products are more likely to have fully developed Web sites and actively promote their URLs through traditional media such as newspaper and TV than are those selling low-Web-fit products. Toll-free numbers, on the other hand, should have moderate cue-relatedness with a wide variety of products including both high- and low-Web-fit products. This is because toll-free numbers are more ubiquitous and less novel than URLs.

According to Shavitt et al. (1994), cue relatedness does not impact initial attitudes under low-involvement conditions because low involvement prohibits the judgment of relevance between peripheral cues and products. However, cue relatedness should have an impact on attitude persistence (Sengupta et al. 1997). Petty and Krosnick (1995) defined attitude persistence as "the extent to which a newly changed attitude endures over time even if it is never directly attacked" (p.100). According to the traditional ELM view, attitude persistence will be greater under the effortful, issue-relevant cognitive activity of high-involvement conditions.

However, there is research suggesting that under low-involvement conditions, some peripheral cues can exert a persistent impact on brand (Sengupta et al. 1997). The rationale is that under low-involvement conditions, a related ad cue will have greater associative strength with a product than will an unrelated ad cue, which leads to greater attitude persistence.

URLs are a more related cue for high-Web-fit products than would be a toll-free number. For low-Web-fit products, a toll-free number may be a more related cue than a URL due to the frequent presence of toll-free numbers across various product ads. Under low-involvement conditions, related cues should induce attitude persistence while unrelated cues should result in attitude decay over time. In high-involvement conditions, the processing itself should result in attitude persistence irrespective of the cue type.

H3a: Under low-involvement conditions for high-Web-fit products, subjects will have more persistent attitudes toward brands with a URL in their ads than toward brands with a toll-free number in their ads as a source-contact cue.

H3b: Under low-involvement conditions for low-Web-fit products, subjects will have more persistent attitudes toward brands with a toll-free number in their ads than toward brands with a URL in their ads as a source-contact cue.

H4: Under high-involvement conditions, brand attitude persistence will not be affected by cue relatedness of URLs or toll-free numbers.

METHOD

Subjects and Design

Subjects were 132 males and females recruited from undergraduate business courses and ranging in age from 19 to 38 years old. They were randomly assigned to the cells of a 2 (high-/low-Web-fit product) x 3 (URL/toll-free number/neither source-contact cue) x 2 (high-/low-involvement condition) mixed design with high-/low-Web-fit product as a within-subject factor. Subjects viewed two product ads and reported their attitudes. Initial and delayed attitude measures were involved (time as another within-subject factor).

Involvement Manipulation

Verbal instructions were used to manipulate message involvement. Under the high-involvement condition, subjects ere informed: "A new product XXX and its ad will be available in (the city) next month. (This university) has been asked to participate in a study designed to provide feedback to the advertiser. You are one of only a few groups to evaluate the products and ads. So your responses are extremely important to us. Your task is to examine the ad in front of you and evaluate the advertised brands. Please pay attention to the claim made by the advertisers." This manipulation is similar to that used by Petty and Cacioppo (1983). Under the low-involvement condition, subjects were asked to review the ad for writing style and overall appearance. These subjects received no information about the availability of the products in their local area. This method was adapted from similar low-involvement instructions used in other studies (Mackenzie and Spreng 1992).

Products and Cue Relatedness

A pretest was conducted to choose a high-web-fit product with high cue relatedness for URLs but less for toll-free numbers and a low-Web-fit product with high cue relatedness for toll-free number but less for URLs. For a variety of products and services, subjects answered the following seven-point semantic differential scale: "Please indicate how likely you think it is that companies selling the following products or services would have a Web site? (Assume that you do NOT recognize the name of the company and only know the product category.)" The scale was anchored by "not likely" and "very likely." The same question was asked about having a toll-free number for the various products and services.

Computer keyboards and paper towels were selected to represent high-Web-fit and low-Web-fit products, respectively. As the pretest indicated, computer hardware (such as a keyboard) had a high score for both presence of URLs (X=6.80) and toll-free numbers (X=5.75). However URL was more cue-related for computer keyboards than was toll-free number (t (45)=2.33, p<0.05). For paper towel, toll-free number (X=2.04) was slightly more cue-related than URL (X=1.85) although not significantly (t (45)=0.53, p<0.20). Therefore, for computer keyboard, URL was considered as the related cue, and toll-free number as the unrelated cue while the reverse was true for paper towels. Both products are familiar to students, and both have a relatively small number of salient attributes which made them easy to present in the advertising stimuli.

The Stimuli

The stimuli were full page, black and white print ads of a computer keyboard or paper towel. Each presented a photograph of the product, a headline, the factitious brand name, and four product claims. Strong and weak claims were both present. The only variation across ads other than product category was the presence or absence of a URL or toll-free number at the bottom of the ad. Each product had three ad versions: URL, toll-free number, or neither source-contact cue present.

Procedures and Dependent Measures

After being seated at tables in a large classroom, subjects were told that they would have several minutes to read one draft version of ad for each of the two new products according to the printed instructions. The order of two products was randomized. Subjects were introduced to the experimental task and received the involvement manipulation in their instructions before each ad. They then reviewed their versions of the test ads. After each ad, they were asked to write down any thoughts about the products, the ads, or the companies. Subjects’ involvement while processing the ad was assessed by having them complete two scales: "While reading the ads, I was" very involved/very uninvolved, and paying much attention/paying little attention. They also reported their agreement with the statement "I carefully considered the claims about the product in the ad" on a seven-point scale These measures were combined to form an indicator of involvement during ad processing (a=0.83). This method was adapted from a study by Miniard et al. (1991).

Next, a series of questions that used five-point response scales were completed by subjects. These assessed attitude toward the advertiser, attitude toward the advertisement, brand attitude. Attitude toward the advertisement was represented by the average of four scales: good/bad, irritating/not irritating, like/dislike, and not interesting/interesting (a=0.95). Attitude toward the advertiser were measured by the average of three semantic differential scales: good/bad, pleasant/unpleasant, and favorable/unfavorable (a=0.97). Subjects completed four five-point semantic differential scales assessing their brand attitudes anchored by good/bad, dislike very much/ like very much, pleasant/ unpleasant, and poor quality/high quality. The average of these four scales was the indicator of brand attitude (a=0.96).

Two days later, the experimenters returned to the classes without pre-announcement to administer the delayed measures. Again, subjects were asked to write down everything they could recall about the advertised product, the advertiser, and the advertisement. Then subjects filled out the same questionnaires previously used to reevaluate their attitudes. One additional scale (satisfactory/unsatisfactory) was added to the original brand attitude measures to assure that "attitude persistence was due to actual maintenance of attitude rather than memory for the earlier measure" (Sengupta et al. 1997). Two additional seven-point scales (not relevant/very relevant, and not appropriate/very appropriate) were added and averaged to indicate the cue relatedness of URLs and toll-free numbers for each product category (a=0.91 and a=0.96, respectively). A final question was asked about the purpose of the experiment. After completion, booklets were collected and subjects were fully debriefed.

RESULTS

A total of 112 subjects provided usable responses for computer keyboard and 110 for paper towel. Only 108 subjects completed the survey for both products. There were 17-19 subjects per cell. An analysis of responses concerning the experiment’s purpose indicated that the cover story had been effective.

Manipulation Checks

ANOVA and paired-samples t-tests were used in analysis for the manipulation checks. For both computer keyboard and paper towel, subjects in the high-involvement conditions reported that they were more involved and paid more attention to the claims about the products than did those in the low-involvement conditions (computer keyboard: high=4.75, low=3.70, F (1, 106)=13.07, p<0.01; paper towel: high=4.65, low=3.67, F (1,106)=15.86, p<0.01). Also, the results of the recall question showed subjects had more product-related thoughts under high-involvement conditions than under low-involvement conditions (computer keyboard: high=3.82, low=3.03, t (106)=10.05, p<0.01; paper towel: high=3.67, low=3.18, t (106)=6.15, p<0.05). Thus, successful manipulation of involvement was indicated. The manipulation for cue relatedness was also very successful. Paired-samples t-tests showed that URLs were more related to computer keyboards than toll-free number (URLs=5.51, toll-free numbers=5.19, t (107)=2.26, p<0.05), and toll-free numbers were more cue related to paper towels than URLs (toll-free numbers=4.07, URLs=3.18, t (107)=4.93, p<0.001).

Hypotheses Testing

A mixed-model ANOVA, with product as a within-subjects factor, was used to examine the effects of different cue types on initial attitude formation under high- and low-involvement conditions across product categories. Table 1 presents the means and stanard deviations for initial attitudes.

The main effect of cue type was significant for brand attitude (F(2, 102)=4.08, p=0.02), attitude toward advertiser (F(2,102)=8.67, p<0.001), and attitude toward advertisement (F(2,102)=3.17, p<0.05). No interactions were significant. This indicated that different cue types had a significant impact on initial attitude formation for both products under high- and low-involvement conditions. Thus, H2 was not supported. Further, planned contrasts revealed that subjects had more positive attitude toward the advertiser, the advertisement, and the brand with URLs than with neither source-contact cue present (p<0.001, p<0.02, and p<0.01, respectively). Contrary to our expectation, there was no significant difference on initial attitude when toll-free numbers were included in their ads and when no source-contact cue was present (all p>0.10). It is possible that the common presence of the toll-free number may have diminished its value. Thus, H1a was only partially supported.

Planned contrasts also revealed that, subjects had more positive attitude toward the advertiser with URLs than with toll-free numbers in the ads (p=0.02). However, this was not true for brand attitude and attitude toward the advertisement (p=0.25 and p=0.31, respectively). It seems that the novelty of URLs (in comparison with toll-free numbers) only affects attitude toward the advertiser, but this effect is not transferred to brand attitude and attitude toward the advertisement. Thus, these findings provided only partial support for H1b.

H3a, H3b, and H4 were tested by examining the differences between the initial brand attitude measures and delayed attitude measures toward both products under high-and low-involvement conditions. Table 2 shows the means and standard deviations for brand attitudes.

TABLE 1

MEANS AND STANDARD DEVIATIONS BY CONDITIONS

TABLE 2

MEANS AND STANDARD DEVIATIONS FOR BRAND ATTITUDES BY CONDITIONS

A mixed-model ANOVA, with time and product as two within-subjects factors, revealed a marginally significant four-way interaction of product with time with involvement and cue type (F(2,102)=2.48, p<0.10). More importantly, under low-involvement conditions, the three-way interaction of cue type with time and product achieved marginal significance (F(2,51)=4.01, p=0.06). This indicated that, as predicted, cue relatedness had an impact on attitude persistence under low-involvement conditions. To provide further clarification, a paired-samples t test was employed to test the difference between initial attitude and delayed attitude across conditions.

The results show that under low-involvement conditions for a computer keyboard, subjects did not experience a decay in attitude toward the brand with URLs (t=0.48, p=0.89). However, attitudes toward the brand when neither cue was present decayed significantly over time (t=3.17, p<0.01). The decay was not significant for presence of a toll-free number (t=1.06, p<0.20). This offers partial support for H3a. While a toll-free number is a less related cue for high Web-fit products, its fairly high score (X=5.21) on the cue-relatedness scale (ranging from 0 to 7) may account for the finding of less attitude decay than expected under the low-involvement condition.

Hypothesis 3b was supported. For the paper towel, subjects in the low-involvement condition did not indicate decay in attitudes when ads incorporated a toll-free number (t=-0.11, p=0.90) while brand attitudes decayed significantly when either a URL or no source-contact cue were present (URLs t=2.30, p<0.05; None t=2.23, p<0.05). Thus, a related cue (toll-free number) generated more persistent brand attitude than an unrelated cue (URLs) under low-involvement conditions.

Under high-involvement conditions, the three-way interaction of cue type with time and product was not significant (F(2,51)=0.29, p=0.75). Moreover, the paired-samples t-tests indicated that under high-involvement conditions attitude changes were not significant (all p>0.10). These results are consistent with our prediction that under high-involvement conditions, cue relatedness had no impact on attitude persistence supporting Hypothesis 4.

inally, while not one of our stated hypotheses, the mixed-model ANOVA indicated that there was a strong interaction of involvement with time (F(1,102)=5.90, p<0.02), which demonstrated that greater persistence occurred under high-involvement conditions than under low-involvement conditions (Sengupta et al. 1997).

GENERAL DISCUSSION

Summary and Implications

According to the ELM, the source-contact cues (URLs or toll-free numbers), as peripheral cues, may have positive effect on initial attitude formation only under low-involvement conditions. However, our study found that under both high- and low-involvement conditions, source-contact cues can have significant impact on initial attitudes. A possible explanation is that URLs or toll-free numbers may not only serve as "peripheral cues" but also as strong "arguments" which may play an important role in attitude formation under high-involvement conditions. Moreover, we found that subjects had more positive attitude when URLs were present than when neither cue was present. However, toll-free numbers in ads did not have such effect. Nor was the attitude difference between URLs and toll-free numbers significant (except attitude toward the advertiser).

Our study found that when a source-contact cue was strongly associated with the advertised product, it produced greater attitude persistence even under low-involvement conditions. When an unrelated cue was used, brand attitude decayed over time. These findings are consistent with the explanation of Sengupta et al. (1997).

Our study also found that under high-involvement conditions, cue relatedness had no impact on initial attitude formation and attitude persistence regardless of product categories. In addition, attitude persistence was found to be greater under high-involvement conditions than under low-involvement conditions. These results are consistent with the prediction of the ELM (Petty and Cacioppo 1983, 1986).

According to our findings, under both high- and low-involvement conditions, ads with URLs will generate more positive attitudes than will ads without any source-contact cue present. More importantly, for high-Web-fit products, subject will have more persistent brand attitude when URLs are present in the ads. For low-Web-fit products, toll-free numbers in ads will lead to persistent attitude but URLs can lead to significant decay in brand attitude. Our findings suggest that URLs should be included in high-Web-fit product ads and made highly noticeable in the ads and for low-Web-fit products, both URLs and toll-free numbers should be included to help subjects form more positive attitude that hopefully will persist.

Limitation and Future Research

Our low-involvement instructions actually generated a moderate level of involvement. Since level of involvement can moderate the effect of source-contact cue on brand attitude formation and attitude persistence, this may have influenced our results. Given that the study was conducted in a lab setting with students as subjects, there are limitations to generalizing the results across other conditions. Our study used only one product category to represent high- and low-Web-fit products, respectively. Additional product categories should be studied.

Further research should consider other influencing variables such as cue attractiveness and argument strength. So far, several studies (Miniard et al. 1994; Sengupta et al. 1997) have manipulated cue relatedness by controlling cue attractiveness. The interaction of product category, cue type, level of involvement, and argument strength should also be examined to determine their impact on attitude persistence. In addition, the whole question of what is a related versus unrelted cue is not clearly defined. Thus one can ask, at what extent of relatedness between cues and objects will attitude persistence be generated? This is a question for future research.

We addressed the impact of URLs and toll-free numbers on attitude separately. However, many advertisers have included both source-contact cues in their ads. It would be interesting to examine the joint impact across all conditions when both cues are present. Finally, as more and more companies representing different product categories do business on the Web, the distinction between high- and low-Web-fit products may disappear. Thus the impact of URL presence on brand attitude may change in the future. This merits further consideration.

REFERENCES

Berthon, Pierre, Leyland F. Pitt, and Richard T. Watson (1996), "The World Wide Web as an Advertising Medium: Toward an Understanding of Conversion Efficiency," Journal of Advertising Research, 36(1), 43-54.

Gupta, Sunil and Rabikar Chatterjee (1997), "Consumer and Corporate Adoption of the World Wide Web as a Commercial Medium," in Electronic Marketing and the Consumer, ed. Robert A. Peterson, Thousand Oaks, CA: SAGE, 123-138.

Industrial Marketing (1978), " #800’ Number-Overlooked Sales Tool," 63(August), 41-44.

Kassaye, Wossen W. (1997), "Global Advertising and the World Wide Web," Business Horizons, May-June, 33-42

Le Forestier, David (1993), "Customer service demands are met by 800 service," Telemarketing Magazine, 11(10), 63-66.

Mackenzie, Scott B. and Richard J. Lutz (1989), " An Empirical Examination of the Structural Antecedents of Attitude toward the Ad in an Advertising Pretesting Context," Journal of Marketing, 53 (April), 48-65.

Mackenzie, Scott B. and Richard A. Spreng (1992), " How Does Motivation Moderate the Impact of Central and Peripheral Processing on Brand Attitudes and Intentions," Journal of Consumer Behavior, 18 (March), 519-529.

Maddox, Lynda M., Mehta Darchan and Daubek G.Hugh (1997), "The Role an Effect of Web Addresses in Advertising," Journal of Advertising Research, March/April, 47-59.

Miniard, Paul W., Sunil Bhatla, Kenneth R. Lord, Peter R. Dickson, and H. Rao Unnava (1991), "Picture-based Persuasion Process and the Moderating Role of Involvement," Journal of Consumer Research, 18(June), 92-107.

Park, C. Whan, Sandra Milberg, and Robert Lawson (1991), "Evaluation of Brand Extensions: The Role of Product Feature Similarity and Brand Concept Consistency," Journal of Consumer Research, 18(September), 185-193.

Park, C. Whan and S. Mark Yong (1986), "Consumer Response to Television Commercials: The Impact of Involvement and Background Music on Brand Attitude Formation," Journal of Marketing Research, 13(February), 11-24.

Petty, Richard E. and John T. Cacioppo (1983), "Central and Peripheral Routes to Advertising Effectiveness: The Moderate Role of Involvement," Journal of Consumer Research, 10 (Sep.) 135C146.

Petty, Richard E. (1986), Communication and Persuasion: Central and Peripheral Routes to Attitude Change, New York: Springer.

Petty, Richard E. and Jon A. Krosnick (1995), Attitude Strength: Antecedents and Consequences, Lawrence Erlbaum Associates.

Sawyer, Alan (1981), "Repetition, Cognitive Responses and Persuasion," in Cognitive Responses in Persuasion, Thomas M. Ostrom, Richard E. Petty, and Timothy C. Brock, ed. Hillsdale, New Jersey: Lawrence Erlbam Associates.

Sengupta, Jaideep, Ronald C. Goodstein and David S. Boninger (1997), "All Cues are not Created Equal: Obtaining Attitude Persistence under Low-Involvement Conditions," Journal of Consumer Behavior, 23(March), 351-361.

Shavitt, Sharon, Suzanne Swan, Tina M. Lowrey, and Michaela Wanke (1994), "The Interaction of Endorser Attractiveness and Involvement in Persuasion Depends on the Goal That Guides Message Processing," Journal of Consumer Psychology, 3(2), 137-162.

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