Susceptibility to Advertising: an Individual Difference With Implications For the Processing of Persuasive Messages

Terri Feldman Barr, Miami University
James J. Kellaris, University of Cincinnati
ABSTRACT - The authors propose that individuals differ with respect to their degree of susceptibility to advertising (STA). Two studies assess the validity of an original, parsimonious measure of STA and examine the role of this trait as a moderator of persuasion processes. Study 1 shows the STA scale to be unidimensional and demonstrates its relationship with other measures of susceptibility to external influences. Study 2 provides additional evidence of validity and shows that persuasion may operate through different mechanisms for low versus high STA individuals.
[ to cite ]:
Terri Feldman Barr and James J. Kellaris (2000) ,"Susceptibility to Advertising: an Individual Difference With Implications For the Processing of Persuasive Messages", in NA - Advances in Consumer Research Volume 27, eds. Stephen J. Hoch and Robert J. Meyer, Provo, UT : Association for Consumer Research, Pages: 230-234.

Advances in Consumer Research Volume 27, 2000      Pages 230-234

SUSCEPTIBILITY TO ADVERTISING: AN INDIVIDUAL DIFFERENCE WITH IMPLICATIONS FOR THE PROCESSING OF PERSUASIVE MESSAGES

Terri Feldman Barr, Miami University

James J. Kellaris, University of Cincinnati

ABSTRACT -

The authors propose that individuals differ with respect to their degree of susceptibility to advertising (STA). Two studies assess the validity of an original, parsimonious measure of STA and examine the role of this trait as a moderator of persuasion processes. Study 1 shows the STA scale to be unidimensional and demonstrates its relationship with other measures of susceptibility to external influences. Study 2 provides additional evidence of validity and shows that persuasion may operate through different mechanisms for low versus high STA individuals.

INTRODUCTION

It is well documented that individuals can be distinguished with respect to their proneness to social influence in consumption attitudes and behaviors (e.g., Bearden, Netemeyer, & Teel 1989; Bearden & Rose 1990). But, whereas many previous studies have focused on individuals’ proneness to the influence of others, far fewer have examined individuals’ proneness to nonpersonal sources of influence. McGuire (1968) proposed that individuals who are likely to be influenced by one source may conform to the suggestions of other sources as well. Hence, a person who is vulnerable to interpersonal influence may be generally prone to a variety of external personal and nonpersonal influence sources.

The research reported here focuses on one important source of nonpersonal influence: mass advertising. Vulnerability to the influence of mass media was discussed in the advertising literature by Moore and Moschis (1978), who proposed it to be an antecedent of materialism among teenagers.

Despite the rising average number of hours spent watching television (Robinson 1990), and the potentially important social and commercial implications of media vulnerability, this topic has received surprisingly little attention from researchers in the field of marketing. Hence, this research seeks to explicate a "susceptibility to advertising" construct, to develop a parsimonious, psychometrically valid measurement instrument, and to explore the role of individual differences in susceptibility in shaping how consumers process persuasive communication.

STUDY 1

This study seeks to develop and test an original measure of susceptibility to advertising (STA) and to examine the performance of the STA measure as a predictor of related traits and outcomes. Using Moore and Moschis’ (1978) definition of vulnerability as a starting point, the following definition is proposed:

STA is the extent to which individuals attend to and value commercial messages as sources of information for guiding their consumptive behaviors.

Procedure

Scale items were generated to represent susceptibility to advertising (e.g., "Television advertising makes me aware of products that I need.") as per Churchill’s (1979) paradigm. The scale items refer specifically to television advertising (versus advertising in general) to make the exemplars more concrete and because television is so frequently attended-to among members of the participants in this study. College students typically devote 21-23 hours per weekCroughly 20% of their waking hoursCto television viewing (Nielsen Media Research 1996). Each item was followed by a five-point agreement scale (1=strongly agree, 5=strongly disagree) on the initial instrument. On the basis of preliminary work reported by Barr and Kellaris (1997), six of ten items were retained for further testing (see Table 1 for items). Readers interested in further details of item generation can refer to Barr (1993), or contact the authors for additional information.

Subjects and Design

To assess the psychometric properties of the scale, a survey instrument containing the six STA items was administered to 227 respondents (88 males, 139 females) attending classes at several public and private universities in the Midwestern United States. Their ages ranged from 17 to 23 (M=18.6).

This sample is appropriate because late adolescence is a transitional stage during which individual differences in proneness to various external influencs may come into greater relief as college students gain knowledge and experience, and struggle to attain independence from parents (Barr 1993). Hence, there should be ample variance in susceptibility among individuals in this age group, and the context of this research (i.e., television advertising) should be highly familiar and personally relevant to the sample.

To facilitate assessment of nomological validity, the survey instrument contained other measures of proneness to social influences, including Attention to Social Comparison Information (ATSCIBBearden & Rose 1984), Consumer Susceptibility to Interpersonal Influence (CSIICBearden et al. 1989), and materialism (Richins & Dawson 1991). Measures of respondents’ sex and age concluded the survey.

Results

The analysis followed Gerbing and Anderson’s (1988) paradigm for scale development, beginning with an exploratory factor analysis. Results for both studies are summarized in Table 1.

One factor of four items with an eigen value>1 was derived. The factor explained 43.3% of the total variance. All had factor loadings>.65. (See Table 1 for the specific items).

Next, a confirmatory factor analysis was performed (via LISREL VI) on the four-item factor. The confirmatory factor analysis produced fit values that indicate a good fit of the data to the unidimensional model of susceptibility to advertising (X2=2.73, 2 d.f., p=.255; GFI=.994; AGFI=.992; RMSR=.017). No normalized residuals>2 were observed.

Cronbach’s coefficient alpha was .8271. Although it is recognized that validation is an ongoing process (Peter 1981), the statistical evidence suggests that the short STA measure meets the necessary conditions for a construct-valid psychometric measure.

Relation of STA to other constructs. To explore the nomological validity of the STA scale, its relationship to conceptually related constructs reported in the consumer psychology literature was examined. STA scores were expected to be positively associated with measures of Attention to Social Comparison (ATSCI), and Consumer Susceptibility to Interpersonal Influence (CSII), both conformity constructs specific to consumption behaviors, and a measure of Materialism.

TABLE 1

FACTOR ANALYSES FOR STUDIES 1 & 2

Findings show positive, significant associations between STA and ATSCI (r=.1803, p=.003) and between STA and both normative (r=.2332, p<.001) and informational (r=.1520, p=.011) dimensions of CSII. Consistent with McGuire’s (1968) general speculation about conformity to multiple sources, individuals prone to the influence of advertising also tend to rely on others as sources of guidance on their own behavior.

Also consistent with expectations were positive, significant associations between STA and the three dimensions of MaterialismCCentrality (r=.1324, p<.023), Happiness (r=.2398, p<.001), and Success (r=.1946, p<.002). These findings suggest that young consumers who are more prone to the influence of advertising also have a stronger tendency to harbor materialistic values.

Discussion

Empirical evidence suggests that the STA measure meets statistical criteria for construct validity (Gerbing & Anderson 1988; Peter 1981). Associations between STA and established measures of proneness to external influences (ATSCI, CSII, materialism) provide evidence of nomological validity. Provisionally, it seems that individuals can be distinguished in terms of their susceptibility to advertising and that this trait can be reliably measured with the short STA scale.

The next step in this research program involves exploring the role that individual differences in STA might play in shaping the processing of commercials. Previous research (Chaiken 1980; Petty and Cacioppo 1981) suggests multiple processes or "routes" by which persuasion can take place, suggesting that here must be moderator variables that explain contingencies under which persuasion operates by various processes. This idea is explored further in Study 2.

STUDY 2

This study investigates differences in the processing strategies used by individuals with low versus high levels of susceptibility to advertising (STA). Additional evidence of the STA measure’s construct validity was also gathered and assessed.

According to both the Elaboration Likelihood Model (ELM) (Petty & Cacioppo 1981) and Heuristic-Systematic Model (HSM) (Chaiken 1980) frameworks, persuasive communications such as ads are comprised of arguments ("content") and peripheral cues that provide a setting for the message ("context"). Peripheral cues include communicational elements such as characteristics of the source (e.g., spokesperson credibility). The persuasive impact of peripheral cues should depend on the amount (low versus high elaboration) and type of processing (heuristic versus systematic) devoted to the communication. When elaboration is high and processing is systematic, attitudes are formed by critical consideration of all the information conveyed in a communication. Hence peripheral cues, like arguments, should have a direct impact on brand attitudes (central route). When elaboration is low and processing is heuristic, peripheral cues should effect persuasion indirectly (peripheral route).

Given their greater motivation to attend to ads and propensity to believe and value commercial messages, high (versus low) STA individuals should devote more cognitive resources to processing ad information, but may be less critical in their evaluations. Thus, elaboration is extensive; but, rather than adopting systematic processing strategies generally associated with high elaboration, high STA consumers may apply less analytical, heuristic strategies.

As a result, persuasion could operate through dual processes (via direct and indirect paths). For example, consumers with high levels of STA may adopt a heuristic that says "The endorser is/is not credible, therefore the product must be good/bad" (direct effect on Ab). High STAs may also adopt a heuristic that says "I like/dislike the endorser, therefore I like/dislike this ad" (indirect effect, mediated through Aad). Elaboration should increase the likelihood of high STAs adopting multiple heuristics.

By contrast, given their lower level of interest in advertisements, low STAs should devote fewer cognitive resources to processing ad information. Under such low elaboration, source effects should operate on brand attitudes through an indirect path (peripheral route).

Subjects and Design

To assess the role of individual differences in STA in shaping paths to persuasion, a simulation study was conducted using printed scenarios to represent hypothetical television ads with different endorsers to induce variation in respondents’ perceptions of source credibility. Perceived credibility of the endorser ("Source") was measured using a multi-item scale. Subjects’ susceptibility to advertising was assessed using the short STA scale developed in study 1; low and high STA groups were formed via median split. The dependent variables were attitude toward the ad (Aad) and attitude toward the advertised brand (Ab). Structural equations models assessed the relationships among Source, Aad, and Ab for individuals with low versus high levels of STA.

The sample was comprised of one-hundred five (N=105) undergraduate students (69 males, 35 females, 1 sex not reported) drawn from a subject pool at a large, midwestern university. None had participated in study 1. Their ages ranged from 20 to 25 (M=22). Course credit was offered as an incentive to complete the survey.

The survey insrument consisted of printed descriptions of an ad for a fictitious product (CinciBank or Tropical Rain shampoo). Each ad description was preceded by instructions to:

"Imagine that you are watching a program on television. During a commercial break, you see the ad that is described below. Please read the ad description carefully, and try hard to imagine that you are really seeing this ad."

The description that followed began: "The product in the ad is (CinciBank or Tropical Rain), a new brand of (banking services or shampoo)."

To induce variation in perceptions of source credibility, the CinciBank ads featured a spokesperson described as either a financial executive or a blue collar worker; the Tropical Rain shampoo ads featured a spokesperson described as either a sexy, professional model or an ordinary consumer. Thus four scenarios were created, i.e., two versions of an ad for each of two products. Differential levels of source credibility were represented by two exemplars (scenarios) per product to induce greater variability and to increase representation of the construct (Keppel 1982).

Procedure

The procedure involved randomly distributing self-administered questionnaires to volunteers assembled in a large lecture auditorium. Each questionnaire contained printed instructions, an ad scenario, and the measures described below. No violations of the instructions were observed.

Measures of Attitudes. Evaluative measures of attitude toward the ad (Aad) and attitude toward the advertised brand (Ab) were adopted from multiple sources (e.g., Madden, Allen, & Twible 1988). The Aad measure consisted of six, seven-point semantic differential items: "Good/Bad, Likeable/Unlikeable, Interesting/Boring, Tasteful/Tasteless, Pleasant/Unpleasant, Appealing/Unappealing," preceded by the prompt "The ad I imagined seeing was..." The Ab measure consisted of the same six items preceded by the prompt "The brand in the ad was..." Alpha reliabilities for the summed and averaged scales were .8855 for Aad and .9194 for Ab. Because Aad and Ab were measured using the same set of items, an analysis sought to establish discriminant validity. The average variance extracted values were both greater than .50 (.587 for Aad and .670 for Ab), and greater than the square of the structural link between the two constructs (.274), providing strong evidence of Aad-Ab discriminant validity (Dillon & Goldstein 1984).

Measure of Source credibility. To facilitate a path analysis, the questionnaires contained a multi-item measure of perceived credibility of the endorser (Source). According to prior research on source credibility, the impact of endorsers can stem from characteristics such as expertise, attractiveness, likeability, and similarity to the audience (e.g., McCracken 1989; Sternthal, Dholakia, & Leavitt 1978). Hence, four seven-point agreement scales (1=strongly disagree, 7=strongly agree) were used to measure the perceived expertise ("The spokesperson in the ad seemed knowledgeable"), perceived attractiveness ("The spokesperson I imagined was physically attractive"), perceived likeability ("The spokesperson in the ad seemed likeable"), and perceived similarity ("I can identify with the spokesperson in the ad") of the fictitious endorser in the ad scenarios. To assess the validity of this original Source measure, a confirmatory factor analysis was performed (via LISREL VI). The confirmatory factor analysis produced fit values that indicate a good fit of the data to the unidimensional model of source credibility (X2=9.25, 2 d.f., p=.010; GFI=.961; AGFI=.952; RMSR=.058). No normalized residuals>2 were observed. The four items were summed and averaged to form a composite source credibility score. Alpha reliability of the original, four-item Source index is .7358.

Measure of Susceptibility (STA). Individual differences in susceptibility to advertising were assessed using the short STA scale developed in study 1. Low and high STA groups were created via median split. The questionnaire concluded with some standard demographic items, used for the purpose of describing the sample.

Results

Seeking additional evidence of the STA scale’s validity, a confirmatory factor analysis was performed (via LISREL VI) on the four-item measure developed in study 1. Factor loadings were .724, .652, .538, and .785 for the four scale items (see Table 1). Fit values indicate an acceptable fit of the study 2 data to the unidimensional model of susceptibility to television advertising (X2=13.99, 2 d.f., p=.001; GFI=.933; AGFI=.916; RMSR=.065). No normalized residuals>2 were observed. Alpha reliability of the four-item summed scale is .7629. Again, statistical evidence suggests that the short STA measure meets the necessary conceptual and empirical conditions for construct validity.

To attain the requisite base size, the analysis aggregated data across scenarios and treated the individual as the analytic unit. A maximum-likelihood estimation procedure using LISREL VI was employed to examine relationships among Source, Aad, and Ab for low versus high susceptibility groups respectively. A fully-saturated model with zero degrees of freedom was specified for each susceptibility group.

Source Effects on Low STA Individuals. The path estimates show significant, non-zero paths from Source to Aad (g1,1=.490, t=3.20), and from Aad to Ab (b2,1=.391, t=2.59). By contrast, the path from Source to Ab (g2,1=.265, t=1.67) is not significantly different from zero. The squared multiple correlations for the endogenous variables are .217 (Aad) and .319 (Ab), indicating that the model accounts for between 21-32% of the variance in the outcome variables. The standardized residuals are normally distributed about 0, indicating that no specification error is present.

Source Effects on High STA Individuals. The path estimates show significant, non-zero paths from Source to Aad (g1,1=.548, t=4.52), from Aad to Ab (b2,1=.429, t=4.96), and, importantly, from Source to Ab (g2,1=.320, t=3.32). Hence persuasion appears to take place through multiple (direct and indirect) paths among high STAs. The squared multiple correlations for the endogenous variables are .242 (Aad) and .516 (Ab), indicating that the model accounts for between 24-51% of the variance in the outcome variables.

Discussion

It appears that the process by which source cues influence brand attitudes differs for individuals with low versus high susceptibility to advertising. Whereas source effects are mediated through Aad among low susceptibles, high susceptibles are persuaded through dual pathsCboth directly and indirectly. This may indicate that high susceptibles (who are more motivated to process ads) engage in "elaborative heuristic processing," using multiple heuristics, or in both systematic and heuristic processing (Chaiken & Maheswaran 1994).

Study 2 also provides additional evidence of the parsimonious STA scale’s unidimensionality (Gerbing & Anderson 1988) and reliability. Hence, statistical evidence from two samples (N=227 and N=105) indicates that the short STA measure meets conditions for inferring construct validity.

It is interesting to note that no direct impact of STA on attitudes was observed in this study. Attitude scores were only slightly more positive among high (versus low) susceptibles for both Aad (MSTA=lo=4.70, MSTA=hi=4.81; t=1.05) and Ab (MSTA=lo=4.85, MSTA=hi=4.95; t=1.09). As a trait variable, STA seems to operate solely through the clasic Person-by-Environment interaction as a moderator of ad effects and persuasion processes. A priori low (versus high) susceptibles were expected to be generally more critical of ads and products, which should be reflected in lower attitude scores. In retrospect, however, it seems feasible that low susceptibles may have been less involved in the ad-related task they were asked to perform and hence not highly motivated to apply critical thinking. This could account for their higher-than-expected attitude scores, which did not differ statistically from those of the high susceptibles. It would be interesting to include a situational involvement measure or manipulation in a future study, as well as elaboration measures, to further elucidate this issue.

GENERAL DISCUSSION

Several issues were addressed in this research: the dimensionality and measurement of susceptibility to advertising, its relationship to other consumption-related variables, and its role as a discriminator of persuasion processes. Following Gerbing and Anderson (1988), the STA construct domain was represented by six scale items, four of which were ultimately confirmed in the unidimensional conceptualization. Although scale development is an on-going process, weight of evidence from two studies suggests that the short STA scale meets the necessary conditions for a construct-valid measure, both conceptually and empirically.

In seeking evidence of nomological validity, this study examined the relationship of STA to other measures of influence-related constructs. Results support McGuire’s notion that influenceable consumers are likely to be susceptible to multiple sources of influence, both personal and impersonal. Positive associations were observed among STA scores and each of the consumer influence scales (ATSCI, CSII), suggesting that the tendency towards compliance appears across sources of influence. Additionally, the relationship between STA and materialism was examined. Positive correlations suggest that young adults who are highly susceptible to advertising are likely to hold materialistic attitudesCspecifically, that material possessions are necessary for happiness, and success, and that they are central to their lives.

Evidence from study 2 suggests that the processes by which source effects operate may differ for individuals with low versus high susceptibility to advertising. Low susceptibles appear to engage in simple heuristic processing, i.e., good endorsers lead to positive affective evalutions of the ad, which "transfer" to brand attitudes. High susceptibles, by contrast, appear to engage in more complex processing. Because of their differing receptivity to information conveyed in ads and the different values they place on this information, low versus high susceptibles are differentially motivated to attend to and think about ads. Different motivational states should lead to different patterns of elaboration. Clearly, low susceptibles are motivated to elaborate less and high susceptibles to elaborate more.

The exact nature of this elaboration, however, is unclear. At least two explanations for the observation of dual paths among high STA individuals seem feasible. First, high susceptibles may engage in heuristic processing using multiple heuristicsCa pattern the authors label "elaborative heuristic processing." This seems feasible because, given their greater receptivity to ads, high susceptibles should be more likely to think aboutCbut less likely to evaluate criticallyCcommercial information, such critical evaluation being more characteristic of systematic processing. Hence, their elaboration could involve the application of multiple heuristics leading to persuasion through both direct ("a credible endorser implies a good product") and indirect ("I like the spokesperson, therefore I like the ad") paths.

Second, high susceptibles may engage in both systematic and heuristic processing of source cues concurently. This hypothesis stems from the sufficiency principle of the HSM. As Chaiken and Maheswaran (1994) point out, higher levels of motivation (personal relevance, task importance) should lead people to desire greater levels of confidence in their evaluations. As the minimum confidence level with which people are comfortable ("sufficiency threshold") shifts upward, systematic processing should be elicited. Among high susceptibles, an uncritical orientation toward commercial information should evoke heuristic processing, but high personal relevance of the information should motivate systematic processing. Hence, dual processes.

Yet a third possibility is that these process explanations (multiple heuristics versus dual processes) are not mutually exclusive, but rather operate under different circumstances. Our data are consistent with both explanations. Lack of cognitive trace data and confidence measures in the present study make it impossible to ascertain the precise processing strategy used by high susceptibles, or the circumstances under which one or the other prevails. This should be a priority for future research, which should also include manipulations of argument quality as well as source credibility.

The present findings suggest the intriguing possibility that, like other person traits, susceptibility (STA) may help explain important contingencies underlying judgmental processes (Moore, Smith, & Gonzalez 1997). STA holds the potential to provide insight into the impact of endorsers and other peripheral cues on the formation of brand attitudes. Moreover, STA may moderate the impact of communication on brand evaluations and on other measures of advertising effectiveness. Hence, we can envision many useful applications of this short scale. For example, it seems reasonable to speculate that executional features of ads such as endorsers, music, and humor will have a more positive impact on consumers who are highly susceptible to advertising in general, and that the effects should obtain through dual (direct and indirect) paths. The investigation of this general proposition and further development of the STA construct must be commended to future consumer research.

REFERENCES

Barr, T.F. (1993). "On Their Own: The Effects of Independence on the Consumer Skills, Attitudes, Motives, and Misbehaviors of Late Adolescents." Unpublished dissertation, University of Cincinnati.

Barr, T.F. & Kellaris, J.J. (1997). "Susceptability to television advertising: A note on its measurement and impact." Proceedings of the Society for Consumer Psychology 1996 Summer Conference, Toronto, ONT: American Psychological Association, pp. 102-105.

Bearden, W.O., Netemeyer, R.G., & Teel, J.E. (1989). "Measurement of consumer susceptibility to interpersonal influence." Journal of Consumer Research, 15, 473-481.

Bearden, W.O., & Rose, R. L. (1990). "Attention to social comparison information: An individual difference factor affecting consumer conformity." Journal of Consumer Research, 16, 461-471.

Chaiken, S. (1980). "Heuristic versus systematic information processing And the use of source versus message cues in persuasion." Journal of Personality and Social Psychology, 39, 752-766.

Chaiken, S., & Maheswaran, D. (1994). "Heuristic processing can bias systematic processing: Effects of source credibility, argument ambiguity, and task importance on attitude judgment." Journal of Personality and Social Psychology, 66, 460-473.

Churchill, G.A., Jr. (1979). "A paradigm for developing better measures of marketing constructs." Journal of Marketing Research, 16, 64-73.

Dillin, W.R., & Goldstein, M. (1984). Multivariate Analysis: Methods and Applications. New York: Wiley.

Gerbing, D.W., & Anderson, J.C. (1988). "An updated paradigm for scale development incorporating unidimensionality and its assessment." Journal of Marketing Research, 25, 186-192.

Keppel, G. (1982). Design & Analysis, 2nd ed. Englewood Cliffs, NJ: Prentice-Hall.

Madden, T.J., Allen, C.T., & Twible, J.L. (1988). "Attitude toward the ad: An assessment of diverse measurement indices under different processing sets." Journal of Marketing Research, 25, 242-252.

McCracken, G. (1989). "Who is the celebrity endorser? Cultural foundations of the endorsement process." Journal of Consumer Research, 16, 310-321.

McGuire, W.J. (1968). "Personality and susceptibility to social influence." In Handbook of Personality Theory and Research, eds. E. F. Borgatta and W. W. Lambert, Chicago: Rand McNally, 1130-1187.

Moore, R.L., & Moschis, G.P. (1978). "Teenagers’ reactions to advertising." Journal of Advertising, 7, 24-30.

Moore, S. R., Smith, R. E., & Gonzalez, R. (1997). "Personality and judgmental heuristics: contextual and individual difference interactions in social judgment." Personality and Social Psychology Bulletin, 23, 76-83.

Peter, J.P. (1981). "Construct validity: A review of basic issues and marketing practices." Journal of Marketing Research, 18, 133-145.

Petty, R.E., & Cacioppo, J.T. (1981). Attitudes and Persuasion: Classic and Contemporary Approaches. Dubuque, Iowa: Wm. C. Brown Co.

Richins, Marsha L., & Dawson, Scott (1992). "A consumer values orientation for materialism and its measurement: scale development and validation." Journal of Consumer Research, 19, 303-316.

Robinson, J. P. (1990). "I Love My TV." American Demographics, 12, 24-27.

Sternthal, B., Dholakia, R., & Leavitt, C. (1978). "The persuasive effect of source credibility: Tests of cognitive responses." Journal of Consumer Research, 4, 252-260.

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