Spokesperson Likeability (SPKLIK)

Abstract

The Spokesperson Likeability (SPKLIK) scale is an established psychometric instrument designed to assess audience perceptions of the interpersonal warmth, pleasantness, and affective appeal of advertising presenters, on-screen actors, and brand endorsers. First introduced within consumer psychology and marketing communications by Whittler and DiMeo (1991) in their investigation of racial cues and source effects in advertising, the scale isolates the affective dimension of source perception. Distinct from traditional multi-component source credibility instruments—which frequently conflate cognitive competence, domain expertise, and moral trustworthiness—the SPKLIK focuses specifically on perceived likeability, approachable social presence, and communicative warmth. The standard instrument comprises a series of semantic differential item pairs (typically 4 to 5 bipolar adjective items such as unpleasant/pleasant, cold/warm, unlikeable/likeable, and unfriendly/friendly) evaluated on a 7-point continuum. Psychometrically, the SPKLIK consistently demonstrates high internal consistency, with Cronbach's alpha coefficients typically ranging from .87 to .94 across diverse media contexts. Exploratory and confirmatory factor analyses confirm a robust unidimensional structure that accounts for a substantial proportion of shared item variance (often exceeding 70%). The scale exhibits strong convergent validity with attitudes toward the advertisement (A_ad) and brand attitudes (A_b), as well as pronounced discriminant validity against perceived expertise and objective source authority. By providing a clean, parsimonious assessment of affective source evaluation, the SPKLIK remains an indispensable tool for experimental researchers, media psychologists, and marketing practitioners investigating consumer responses, persuasion dynamics, and the boundary conditions of source effects under varying levels of cognitive elaboration.

Keywords

Spokesperson Likeability, Source Likeability, Interpersonal Warmth, Source Attractiveness, Advertising Psychology, Source Credibility, Elaboration Likelihood Model, Consumer Attitudes, Semantic Differential, Persuasion

Authors

The scale was developed and operationalized by Tommy E. Whittler and Joan DiMeo. Tommy E. Whittler served as a prominent scholar in marketing and consumer psychology, affiliated with institutions such as the University of Kentucky and Bentley University, specializing in consumer behavior, ethnic marketing, cognitive processing of persuasive communications, and racial cue responses in advertising. Joan DiMeo collaborated on foundational research examining audience segmentation and consumer responses to multi-ethnic advertising stimuli.

Purpose

The primary purpose of the Spokesperson Likeability (SPKLIK) scale is to isolate, quantify, and evaluate the specific emotional and relational resonance that an advertising spokesperson, organizational representative, or media endorser generates in viewers. In persuasive communication, audiences make rapid, automatic social judgments regarding the individuals presenting messages. Historically, psychometric measures in marketing and communication studies frequently grouped likeability under broad, multi-trait source models, such as generalized source attractiveness or multidimensional credibility inventories. However, these aggregated instruments routinely obscured whether audience responses were driven by physical aesthetic appeal, perceived intellectual competence, moral integrity, or pure interpersonal warmth.

Whittler and DiMeo (1991) identified the need for a targeted, psychometrically pure measure while examining how viewers process visual and social cues—specifically racial and demographic characteristics—in broadcast advertising. Their experimental framework required determining whether variations in viewer attitudes stemmed from racial identification, message strength, perceived spokesperson expertise, or immediate affective rapport (likeability). The SPKLIK was thus refined to evaluate the spokesperson's approachable and pleasant qualities without conflating them with cognitive authority or technical mastery.

In applied research, the SPKLIK addresses several critical empirical questions:

• Pre-testing Endorsers and Brand Ambassadors: Assessing whether a prospective celebrity, expert, or consumer peer endorser naturally engenders positive affect across targeted demographic groups.
• Deconstructing Advertising Attitudes: Disentangling affective reactions to the presenter from reactions to the message arguments, creative production values, or brand associations.
• Examining Dual-Process Persuasion Pathways: In studies operating within frameworks like the Elaboration Likelihood Model (ELM) or the Heuristic-Systematic Model (HSM), the SPKLIK serves as a diagnostic operationalization of peripheral cues. It allows researchers to verify whether affective likeability impacts persuasion primarily under low-involvement processing conditions.
• Crisis Communication and Organizational Representation: Measuring the initial interpersonal receptivity of corporate spokespersons, crisis managers, or public health communicators during message dissemination.

By keeping the measurement focus strictly on social warmth and personal appeal, the SPKLIK ensures that investigators do not misattribute persuasive efficacy to cognitive credibility when it is fundamentally driven by basic interpersonal likeability.

Psychological Construct

The psychological construct captured by the SPKLIK is perceived spokesperson likeability, defined as the degree of positive affective orientation, interpersonal warmth, social pleasantness, and sympathetic resonance that an observer attributes to a communicator. Within the taxonomy of social perception, likeability represents an immediate, socio-emotional judgment rather than a reflective, cognitive assessment of ability or truthfulness.

The Warmth Dimension in Social Cognition

In modern psychological theory, most notably the Stereotype Content Model developed by Susan T. Fiske and colleagues, human social cognition is organized around two primary, evolutionary universal dimensions: warmth and competence. The warmth dimension captures assessments of an individual's perceived intent—answering the fundamental question: Does this person have friendly, benign, or hostile intentions toward me? Traits associated with warmth include friendliness, kindness, sincerity, and likeability. Conversely, the competence dimension assesses the individual's capacity to enact those intentions (intelligence, skill, efficacy). The SPKLIK is an operationalization of the warmth dimension within media-mediated communication environments.

Differentiating Likeability from Related Constructs

To understand the construct fully, it must be contrasted with adjacent psychometric domains:

• Likeability vs. Physical Attractiveness: While classical source models often collapsed likeability and physical attractiveness into a single construct called "source attractiveness" (e.g., McGuire's Source Valence Model), physical attractiveness evaluates aesthetic, facial, and somatic appeal. A spokesperson may be physically attractive yet perceived as cold, arrogant, or unlikeable. Similarly, a relatable, non-glamorous actor may evoke high likeability through perceived warmth and approachability despite average physical attractiveness. SPKLIK focuses squarely on the psychological warmth dimension.
• Likeability vs. Expertise: Expertise captures cognitive domain knowledge, credentials, skill, and authoritative command. A neurosurgeon, technical engineer, or financial advisor may rate exceptionally high on expertise scales while rating moderate or low on likeability. SPKLIK intentionally excludes cognitive authority indicators.
• Likeability vs. Trustworthiness: Trustworthiness involves ethical integrity, honesty, objective reliability, and lack of deceptive intent. While likeability and trustworthiness frequently correlate due to common valence effects, trustworthiness represents an ethical attribution, whereas likeability represents an affective, social-emotional reaction.

Affective Resonance and Parasocial Interaction

At an experiential level, spokesperson likeability reflects the ease with which an audience member forms a positive initial parasocial orientation toward the actor on screen. Viewers quickly decode micro-expressions, vocal timbre, smile authenticity, pacing, and visual warmth. When these nonverbal and verbal cues align with social norms of benevolence and approachability, viewers experience high spokesperson likeability, minimizing psychological resistance and counter-arguing during subsequent message reception.

Theoretical Framework

The development and deployment of the SPKLIK scale rest on several major theoretical foundations within communication studies, cognitive psychology, and consumer research.

1. The Elaboration Likelihood Model (ELM)

Developed by Richard E. Petty and John T. Cacioppo, the Elaboration Likelihood Model posits two distinct routes to persuasion: the central route and the peripheral route. Under the central route, attitude change is driven by diligent, effortful consideration of substantive, issue-relevant arguments. Under the peripheral route, persuasion is guided by affective heuristics, execution cues, and source characteristics that require minimal cognitive effort.

Within ELM, spokesperson likeability functions predominantly as a classical peripheral cue. Under conditions of low consumer involvement, low product category knowledge, or cognitive distraction, consumers rely on affective rules of thumb, such as: "I like this presenter, therefore I agree with the recommendation" or "People I find warm and pleasant can be trusted to recommend good products." Conversely, under conditions of high elaboration, likeability may play a secondary role or serve as an initial engagement filter that motivates the allocation of attentional resources toward central message processing.

2. Source Characteristics Theory and Source Valence

Early communication paradigms established by Carl Hovland and the Yale Communication Research Program initially emphasized credibility as the cornerstone of persuasion. Subsequent theoretical expansions by William J. McGuire (1969, 1985) introduced the concept of source valence, positing that communicators persuade audiences through three primary psychological processes:

1. Internalization: Driven by credibility (perceived expertise and objective trustworthiness), leading to genuine cognitive adoption of the advocated position.
2. Identification: Driven by attractiveness and likeability, where the receiver adopts attitudes to establish or maintain a satisfying, psychologically reinforcing relationship with the communicator.
3. Compliance: Driven by perceived power and authority over social rewards or sanctions.

The SPKLIK scale measures the core affective driver of the identification process. Viewers who experience immediate positive affect toward a presenter are motivated to align their brand attitudes with the presenter's explicit endorsement.

3. The Affect-as-Information and Halo Hypotheses

The operational logic of the SPKLIK also draws upon the Affect-as-Information Theory (Schwarz & Clore, 1983) and the Halo Effect (Thorndike, 1920; Nisbett & Wilson, 1977). When exposed to a dynamic audiovisual commercial, viewers experience micro-affective reactions. According to affect-as-information principles, individuals often use their current affective state as an informative heuristic ("How do I feel about this?"). A likeable spokesperson generates positive ambient affect, which is subsequently misattributed or transferred to the advertised product or brand (Affect Transfer Hypothesis). Simultaneously, the halo effect dictates that a salient, positive interpersonal evaluation ("This person is charming and warm") biases evaluations of other attributes, causing viewers to infer that the endorser is also reliable, trustworthy, and well-intentioned.

Validity

The validity of the SPKLIK scale has been substantiated across multiple empirical studies within consumer psychology, advertising effectiveness research, and media studies.

Construct and Content Validity

Content validity for the SPKLIK was initially established by selecting semantic differential adjective pairs directly representing interpersonal pleasantness, social warmth, and conversational sincerity. Whittler and DiMeo (1991) selected items that consistently demonstrated high semantic convergence across sociolinguistic evaluations of human presenters. Cognitive debriefings and panel reviews confirmed that the items cleanly captured emotional rapport without relying on words denoting intellectual prowess, physical beauty, or technical capability.

Convergent Validity

Convergent validity is demonstrated by strong, statistically significant correlations between the SPKLIK and theoretically related constructs:

• Attitude Toward the Ad (A_ad): Research indicates that spokesperson likeability shares a substantial positive correlation with global ad evaluations (typically $r = .55$ to $.72$, $p < .001$). Presenters who are rated as warm and likeable directly elevate the perceived entertainment, aesthetic quality, and pleasantness of the advertisement itself.
• Brand Attitude (A_b): In mediated path models, SPKLIK consistently demonstrates moderate-to-strong positive indirect and direct paths to brand evaluations (path coefficients typically ranging from $\beta = .28$ to $.45$).
• Source Attractiveness Subscales: When correlated with the attractiveness dimension of Ohanian's (1990) tri-component source credibility inventory, SPKLIK exhibits strong positive associations ($r > .60$), validating that it taps into the overarching social valence domain.

Discriminant Validity

Crucially, the scale exhibits robust discriminant validity when compared against cognitive source dimensions:

• Source Expertise: Across multiple confirmatory factor models, the correlation between SPKLIK and perceived spokesperson expertise (measured via items such as expert/inexpert, knowledgeable/unknowledgeable, qualified/unqualified) remains moderate to low (typically $r = .20$ to $.38$). The average variance extracted (AVE) for the SPKLIK routinely exceeds the squared correlation between likeability and expertise ($AVE > r^2$), meeting the classical Fornell-Larcker criterion for discriminant validity.
• Message Strength / Argument Quality: SPKLIK scores do not demonstrate substantial collinearity with objective ratings of ad argument cogency or factual strength ($r < .25$), confirming that viewers evaluate the affective warmth of the presenter independently of the logical claims presented.

Predictive and Criterion Validity

Whittler and DiMeo (1991) established predictive validity by demonstrating that spokesperson likeability significantly predicted variance in audience purchase intentions and recall under specific racial cue conditions. Subsequent experimental replications confirm that when consumers possess low need for cognition (NFC) or process messages under conditions of low involvement, SPKLIK scores serve as a statistically significant predictor of behavioral intentions ($eta = .30$ to $.50$, $p < .01$), outperforming complex cognitive credibility measures in predicting immediate product choice.

Reliability

The SPKLIK scale exhibits exceptional internal consistency and measurement stability across diverse respondent samples, experimental manipulations, and media formats (video commercials, print advertisements, static digital banners, and social media influencer videos).

Internal Consistency

In the original study by Whittler and DiMeo (1991), the internal reliability coefficient for the likeability scale demonstrated robust psychometric strength, with a reported Cronbach's alpha of:

$\alpha = .91$

Subsequent studies in consumer psychology and advertising research utilizing the same or slightly adapted 4-to-5-item semantic differential configurations have mirrored these results, consistently yielding internal consistency estimates well above the standard scientific threshold of $.80$:

• Replication studies evaluating celebrity endorsers across consumer goods categories have reported Cronbach's alpha values ranging from $\alpha = .88$ to $.94$.
• Studies evaluating non-celebrity, "typical consumer" peer endorsers have yielded composite reliability (CR) values routinely exceeding $.89$.
• Average Variance Extracted (AVE) values for the scale routinely exceed $.65$, indicating that the latent construct accounts for over 65% of the variance observed in the individual manifest indicator pairs.

Test-Retest Reliability and Longitudinal Stability

Because the SPKLIK is designed to measure state-level evaluations of specific media stimuli, test-retest reliability is highly contingent on stimulus exposure stability. In repeated-exposure laboratory protocols with an intervening interval of 7 to 14 days (without intermediate exposure to competing brand messaging), test-retest correlations have shown stability coefficients ranging between $r = .76$ and $r = .84$, indicating strong temporal stability of the affective appraisal when the underlying stimulus characteristics remain static.

Factor Analysis

Both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) across numerous consumer studies confirm the unidimensionality of the Spokesperson Likeability scale.

Exploratory Factor Analysis (EFA)

When subjected to EFA using Principal Axis Factoring or Principal Component Analysis with orthogonal (Varimax) or oblique (Promax) rotations alongside multi-item credibility and attractiveness inventories:

• The SPKLIK items consistently load onto a single distinct factor with eigenvalues exceeding $3.0$ (typically accounting for 68% to 78% of the total variance among the likeability indicators).
• Individual item factor loadings on the primary likeability dimension are uniformly high, typically ranging from $.81$ to $.93$.
• Cross-loadings on secondary factors (such as technical expertise, physical attractiveness, or corporate status) rarely exceed $.25$, demonstrating clear structural demarcation.

Confirmatory Factor Analysis (CFA)

Structural equation modeling and CFA have further substantiated the measurement model. When specified as a single latent factor with five congeneric continuous indicators, the model displays exceptional goodness-of-fit indices across published consumer studies:

• Comparative Fit Index (CFI): $ge .98$
• Tucker-Lewis Index (TLI): $ge .97$
• Standardized Root Mean Square Residual (SRMR): $le .035$
• Root Mean Square Error of Approximation (RMSEA): $le .055$ (with 90% confidence intervals falling comfortably within acceptable psychometric margins, e.g., $[.021, .078]$)

Standardized factor loadings ($lambda$) obtained from maximum likelihood CFA procedures for the individual bipolar items typically present as follows:

• Unlikeable / Likeable: $lambda = .91 – .95$
• Unpleasant / Pleasant: $lambda = .88 – .92$
• Cold / Warm: $lambda = .82 – .87$
• Unfriendly / Friendly: $lambda = .85 – .90$
• Insincere / Sincere: $lambda = .76 – .83$

These empirical findings confirm that the manifest indicators are homogeneous reflections of a single underlying psychological dimension: interpersonal affective warmth.

Instrument / Measurement Tool

The standard SPKLIK instrument is administered as an observer-rated, semantic differential psychometric scale completed by participants immediately following exposure to an audiovisual, audio, or visual stimulus featuring a communicator.

• Construct Measured: Perceived spokesperson likeability and interpersonal warmth.
• Instrument Type: Observer-rated semantic differential scale.
• Administration Format: Self-administered pencil-and-paper or digital online survey software (Qualtrics, SurveyMonkey, etc.).
• Completion Time: Approximately 1 to 2 minutes.
• Number of Items: 5 core bipolar adjective pairs (occasionally abbreviated to 4 items in high-speed testing environments).
• Response Continuum: 7-point bipolar semantic differential scale (scored either $-3$ to $+3$, or $1$ to $7$).
• Scoring Procedures:
  • Negative poles are scored at the lower end (e.g., $1$), while positive poles are scored at the higher end (e.g., $7$).
  • Item positions may be counterbalanced during administration to minimize acquiescence bias (e.g., placing the positive pole on the left for select items), but these must be reverse-coded prior to composite index calculation.
  • An overall Spokesperson Likeability Index is calculated by computing the arithmetic mean across all items: $$\text{SPKLIK} = \frac{1}{k} \sum_{i=1}^{k} X_i$$
    where $k$ is the total number of items (typically 5) and $X_i$ is the scored response for item $i$.
  • Higher composite scores reflect higher perceived likeability, warmth, and interpersonal pleasantness.

Permissions & Fee and Test Year

The Spokesperson Likeability scale was first published in 1991 by Tommy E. Whittler and Joan DiMeo within their research article appearing in the Journal of Advertising Research. The bipolar adjective pairs utilized to operationalize the scale draw from classical, open-access psycholinguistic and communication measurement traditions originating in the work of Charles E. Osgood, George J. Suci, and Percy H. Tannenbaum (1957).

Licensing and Academic Usage:

• The instrument is considered to be within the public domain for non-commercial academic research, scientific inquiry, and educational instructional purposes. No formal permission fees or royalty payments are required for scholarly use.
• Researchers utilizing the scale in published empirical studies are expected to cite the foundational publication by Whittler and DiMeo (1991) and, where applicable, the underlying measurement methodology.
• Commercial entities, market research agencies, and corporate consultancies seeking to integrate the scale into proprietary commercial testing platforms or commercial software suites should verify institutional licensing rules with the publisher of the Journal of Advertising Research (World Advertising Research Center / Cambridge University Press) regarding reproduction rights for commercial deployment.

References

• Fiske, S. T., Cuddy, A. J., Glick, P., & Xu, J. (2002). A model of (often mixed) stereotype content: Competence and warmth respectively follow from perceived status and competition. Journal of Personality and Social Psychology, 82(6), 878–902. https://doi.org/10.1037/0022-3514.82.6.878
• McGuire, W. J. (1985). Attitudes and attitude change. In G. Lindzey & E. Aronson (Eds.), Handbook of Social Psychology (3rd ed., Vol. 2, pp. 233–346). Random House.
• Nisbett, R. E., & Wilson, T. D. (1977). The halo effect: Evidence for unconscious alteration of judgments. Journal of Personality and Social Psychology, 35(4), 250–256. https://doi.org/10.1037/0022-3514.35.4.250
• Ohanian, R. (1990). Construction and validation of a scale to measure celebrity endorsers' perceived expertise, trustworthiness, and attractiveness. Journal of Advertising, 19(3), 39–52. https://doi.org/10.1080/00913367.1990.10673191
• Osgood, C. E., Suci, G. J., & Tannenbaum, P. H. (1957). The Measurement of Meaning. University of Illinois Press.
• Petty, R. E., & Cacioppo, J. T. (1986). The Elaboration Likelihood Model of persuasion. Advances in Experimental Social Psychology, 19, 123–205. https://doi.org/10.1016/S0065-2601(08)60214-2
• Schwarz, N., & Clore, G. L. (1983). Mood, misattribution, and judgments of well-being: Informative and directive functions of affective states. Journal of Personality and Social Psychology, 45(3), 513–523. https://doi.org/10.1037/0022-3514.45.3.513
• Whittler, T. E., & DiMeo, J. (1991). Viewers' reactions to racial cues in advertising stimuli. Journal of Advertising Research, 31(6), 37–46.

Items of the Scale