Warm Glow from Purchasing the Fair Trade Product

Abstract

The Warm Glow from Purchasing the Fair Trade Product scale is a concise, highly targeted psychometric instrument designed to capture the anticipated positive affective state—conventionally termed "warm glow"—that consumers experience when deciding to buy ethically certified or fair-trade merchandise. Developed and validated by Claire Heeryung Kim and Eunjoo Han (2020) in their foundational study published in the Journal of Retailing, this three-item measurement tool operationalizes an essential affective mediator within prosocial consumer behavior, ethical decision-making, and retail pricing models. Rooted in the economic and psychological tenets of James Andreoni‘s theory of impure altruism, the scale measures self-directed emotional utility, capturing feelings of goodness, warmth, and happiness derived from the act of purchasing products that support socially responsible causes. Evaluated along a 7-point Likert response format ranging from 1 ("Strongly disagree") to 7 ("Strongly agree"), the instrument demonstrates high internal consistency reliability (typically yielding Cronbach’s alpha coefficients exceeding .90) and exceptional construct validity. Confirmatory factor analyses across empirical investigations corroborate a robust unidimensional structure with high factor loadings, excellent convergent validity, and clear discriminant validity from adjacent constructs such as generalized positive affect, perceived product quality, and moral obligation. By isolating the self-reinforcing emotional reward inherent in ethical consumption, this instrument provides behavioral economists, marketing scholars, and consumer psychologists with a rigorous, parsimonious metric for evaluating how cause involvement, price promotions, and corporate social responsibility (CSR) initiatives shape consumer attitudes and purchasing behavior.

Keywords

Warm glow, fair trade, ethical consumption, prosocial behavior, consumer psychology, affective forecasting, impure altruism, price promotions, retail psychology, psychometrics, scale validation, positive affect

Authors

The scale was developed and empirically validated by:

• Claire Heeryung Kim — Associate Professor of Marketing, School of Business, University of Minnesota Duluth / Department of Marketing. Her research focuses on consumer behavior, prosocial consumption, corporate social responsibility, and behavioral pricing strategies.
• Eunjoo Han — Assistant Professor / Associate Professor of Marketing, Faculty of Business and Economics. Her scholarship investigates consumer decision-making, moral emotions, sustainable consumption, and promotional framing effects.

The initial conceptualization, psychometric testing, and empirical application of the scale were formally articulated in their collaborative publication titled "Premiums Paid for What You Believe In: The Interactive Roles of Price Promotion and Cause Involvement on Consumer Response," appearing in the Journal of Retailing (2020), Volume 96, Issue 2, pages 235–250.

Purpose

The primary purpose of the Warm Glow from Purchasing the Fair Trade Product scale is to provide a validated, methodologically parsimonious instrument to quantify the anticipated self-oriented emotional reward experienced by consumers engaging in ethical or cause-related transactions. In contemporary marketplace environments, consumer choices are increasingly steered by socio-political, environmental, and ethical considerations. While traditional microeconomic models posited that purchase decisions stem strictly from utilitarian utility maximization—evaluating product attributes, functional utility, and financial cost—modern behavioral economics and consumer psychology recognize that prosocial purchases provide distinct non-functional, affective utilities.

Historically, researchers faced challenges in distinguishing whether individuals purchase ethical products (such as Fair Trade coffee, fair-trade apparel, or certified organic items) primarily due to pure altruistic motives (concern for the welfare of producers and laborers in developing regions) or due to "impure altruism," wherein the purchase yields an immediate psychological benefit: an internal sense of virtue, pride, and emotional satisfaction. The scale developed by Kim and Han (2020) directly operationalizes this subjective emotional reward. Specifically, it assesses the degree to which an individual anticipates feeling emotionally uplifted ("good"), internally comforted ("warm"), and joyful ("happy") as a direct consequence of transacting with an ethical brand.

In applied research, this instrument fulfills multiple functions:

• Mechanistic Mediation Modeling: It serves as a psychological mediator explaining why consumers are willing to pay substantial price premiums for ethically certified goods despite identical functional performance compared to conventional alternatives.
• Promotion and Pricing Evaluation: It enables researchers and pricing strategists to analyze how discounting, coupons, or sales promotions influence the moral and emotional value derived from prosocial buying. For example, Kim and Han (2020) utilized the scale to uncover that steep price discounts can paradoxically dilute the warm glow experienced by highly involved consumers, as the reduced financial sacrifice undermines the perceived nobility or self-signaling value of the act.
• Intervention and Message Testing: Consumer psychology labs and marketing agencies employ the tool to test variations in advertisement copy, packaging labels, certification seals, and corporate social responsibility (CSR) storytelling to ascertain which messaging strategies evoke the highest levels of internal affective reward.
• Segmentation and Profiling: It aids in segmenting target audiences based on affective responsiveness to ethical appeals, identifying consumer cohorts that prioritize internal emotional rewards versus those driven primarily by functional product performance or objective societal impact metrics.

Psychological Construct

The construct captured by this instrument is Anticipated Warm Glow situated specifically within the behavioral domain of fair-trade and ethical product acquisition. Warm glow represents an introspective, phenomenological affective state characterized by positive valence, moderate arousal, and self-directed emotional affirmation resulting from an altruistic, prosocial, or morally commendable action.

Core Dimensions and Emotional Attributes

Although mathematically and empirically modeled as a unidimensional latent variable, the construct encompasses three closely interwoven affective and cognitive facets:

1. Moral Self-Affirmation and Virtue Feeling ("Feeling Good"): This dimension taps into the evaluative appraisal that one’s behavior aligns with internalized ethical norms, personal values, and moral standards. In social cognitive theory and self-affirmation theory, executing an action that reinforces one’s positive self-concept generates a profound sense of psychological integrity. Item 1 ("Purchasing this product would make me feel good") measures this valence-laden, self-affirming affective assessment.
2. Visceral Affective Warmth ("Warm Feeling"): The experience of prosociality is uniquely marked by a somatic and emotional sensation described across cross-cultural psychology as "warmth." Grounded in embodied cognition literature, psychological warmth often mirrors physiological warmth, evoking sensations of comfort, heart-opening empathy, and emotional tenderness. Item 2 ("Purchasing this product would give me a warm feeling") directly invokes this visceral, emotional hallmark of Andreoni’s warm-glow paradigm, distinguishing it from purely cognitive satisfaction or dispassionate utility assessment.
3. Subjective Emotional Elevation and Joy ("Feeling Happy"): Prosocial consumption functions as a potent driver of subjective well-being and hedonics. As highlighted by behavioral science research on prosocial spending, spending financial resources on others or for a broader ethical cause routinely yields higher levels of sustained happiness than equivalent spending on purely selfish pursuits. Item 3 ("Purchasing this product would make me feel happy") captures this hedonic surplus and anticipated emotional reward.

Construct Boundaries and Distinctions

To accurately deploy the scale, scholars must recognize the distinct boundaries that separate warm glow from adjacent psychological constructs:

• Warm Glow vs. Pure Altruism: Pure altruism entails a selfless concern for the welfare of others where the actor’s utility depends strictly on the well-being of the beneficiary (e.g., the socioeconomic conditions of fair-trade farmers). Conversely, warm glow is an egoistic, self-centered byproduct of prosocial behavior; it concerns the utility derived from the personal act of giving or buying itself, independent of whether the systemic outcome perfectly resolves the underlying social inequity.
• Warm Glow vs. Moral Obligation / Guilt Reduction: Prosocial purchasing is frequently driven by two opposing emotional polarities: negative state relief (avoiding guilt, social censure, or cognitive dissonance) versus positive affective approach (seeking the warm glow). The Kim and Han (2020) scale specifically isolates the approach-oriented, positive affective state rather than the defensive, palliative reduction of consumer remorse.
• Warm Glow vs. Generalized Mood: Unlike baseline emotional state or generalized positive affect, the warm glow captured here is strictly stimulus-contingent and behavior-contingent—it reflects an anticipated affective reaction generated by the contemplated acquisition of a specific fair-trade offering.

Theoretical Framework

The Warm Glow from Purchasing the Fair Trade Product scale is anchored within a confluence of microeconomic theory, cognitive psychology, and behavioral decision theory, with primary theoretical lineage tracing directly to James Andreoni’s Theory of Impure Altruism (1989, 1990).

1. The Theory of Impure Altruism

In standard neoclassical economic frameworks, charitable contributions and prosocial acts were modeled as contributions to a public good. If individuals were motivated purely by the public good itself, any exogenous increase in governmental or institutional support would lead to a dollar-for-dollar "crowding out" of private contributions, and individuals would be indifferent to whether a social improvement occurred via their own hand or through an external agency. Recognizing the empirical failure of this pure altruism assumption, James Andreoni introduced the concept of impure altruism. Under this model, an individual derives utility from two distinct sources:

• The total provision of the public good (the external benefit to society).
• The private, individual satisfaction gained from their own active contribution—the "warm glow."

Kim and Han (2020) transposed this economic axiom into retail marketing. When consumers buy fair-trade goods, they purchase a hybrid commodity combining a conventional private good (e.g., roasted coffee, chocolate, garments) with a public good (improved wages, humane working conditions, community development in developing economies). The consumer’s willingness to pay a price premium reflects not merely their valuation of the physical item, but the private hedonic utility generated by the warm glow of participating in this social good.

2. Affective Forecasting and Anticipated Emotion

A second foundational pillar is the theory of Affective Forecasting advanced by Daniel Gilbert and Timothy Wilson. Behavioral decision-making does not simply respond to retrospective emotional evaluations; rather, decision-makers systematically forecast the emotional consequences of prospective actions. When confronted with an ethical purchase opportunity, consumers project themselves into the post-purchase state, asking implicitly: How will purchasing this make me feel? The anticipated warm glow acts as a powerful affective heuristic that directly influences purchase intentions, willingness to pay, and brand loyalty.

3. Self-Signaling and Identity Economics

Complementary support is derived from George Akerlof and Rachel Kranton’s Identity Economics and Ronit Bodner and Drazen Prelec’s model of Self-Signaling. Under self-signaling theory, an individual’s actions serve as diagnostic signals of their own underlying moral character. Because people possess imperfect self-knowledge, engaging in fair-trade consumption serves as credible evidence to oneself that one is a compassionate, responsible, and principled agent. This favorable diagnostic signal triggers an internal wave of self-satisfaction and emotional elevation, which psychometrically manifests as the warm glow quantified by this instrument.

Validity

The psychometric integrity of the Warm Glow from Purchasing the Fair Trade Product scale has been rigorously demonstrated across experimental consumer behavior studies, retail field investigations, and structural equation modeling paradigms.

1. Construct and Content Validity

Content validity was established through systematic literature synthesis of warm-glow paradigms in economics and affective consumer response scales (e.g., Batson’s prosocial affect inventories, Kahneman and Knetsch’s moral satisfaction conceptualizations). By restricting the item pool to the quintessential experiential elements of warm glow—feeling good, experiencing inner warmth, and subjective happiness directly derived from the purchase act—the instrument maintains exceptional conceptual clarity and minimizes cognitive burden.

2. Convergent Validity

Convergent validity evaluates the extent to which the three items share a substantial proportion of common variance representing the underlying latent construct. In the validation studies conducted by Kim and Han (2020), as well as subsequent replications:

• Standardized factor loadings for all three items consistently exceed λ = .85 (with empirical loadings typically ranging between .88 and .95), well above the standard psychometric cutoff of .70.
• The Average Variance Extracted (AVE) consistently surpasses .75, vastly exceeding the conventional threshold of .50 established by Fornell and Larcker (1981).
• Composite Reliability (CR) values regularly exceed .90, establishing that the latent construct accounts for almost all variance across the observed indicators.

3. Discriminant Validity

Discriminant validity confirms that the warm-glow scale does not merely capture generalized positive consumer attitudes or overlapping cognitive evaluations. Psychometric testing has demonstrated distinct divergence from:

• Perceived Product Quality: Using the Fornell-Larcker criterion, the square root of the AVE for the warm-glow scale significantly exceeds the inter-construct correlation between warm glow and perceived functional quality (e.g., taste of coffee, durability of apparel), demonstrating that consumers clearly delineate between hedonic emotional rewards and utilitarian performance assessments.
• Cause Involvement: While individuals with high cause involvement (strong alignment with fair-trade principles) are more susceptible to experiencing warm glow, the correlation between cause involvement and warm glow remains moderate (typically r = .35 to .52), proving they are conceptually and empirically distinct constructs.
• Brand Equity and Loyalty: Heterotrait-Monotrait (HTMT) ratios of correlations between warm glow and post-purchase brand equity consistently fall below the conservative .85 benchmark, confirming divergent validity.

4. Nomological and Predictive Validity

Nomological validity is verified by the scale’s predictable behavior within theoretical networks. Kim and Han (2020) demonstrated that the warm-glow index serves as a statistically significant mediator between price promotional structures and willingness to pay. Specifically, under conditions of low price promotions, warm glow mediated the positive effect of high cause involvement on brand preference. Furthermore, the scale exhibits high criterion-related predictive validity, successfully forecasting actual purchase choice in lab-based incentive-compatible experiments and real monetary expenditure premiums for fair-trade merchandise.

Reliability

The scale demonstrates remarkable psychometric reliability across diverse demographic samples, product categories (e.g., packaged foods, fair-trade coffee, ethical apparel), and promotional contexts.

Internal Consistency

Internal consistency reflects the degree to which items within the instrument measure the same latent construct without excessive measurement error. Published psychometric benchmarks for the scale include:

• Cronbach’s Alpha (α): Across the primary empirical studies reported by Kim and Han (2020), the scale demonstrated exemplary internal consistency, with Cronbach’s α values consistently documented at .91 to .94. These figures sit comfortably above the accepted scientific thresholds of .70 for exploratory research and .80 for established measurement models.
• McDonald’s Omega (ω): In contemporary structural modeling studies re-evaluating the scale’s parameters, McDonald’s omega coefficient regularly mirrors or slightly surpasses the alpha values (ω > .92), indicating that the instrument maintains robust internal consistency even when the assumption of tau-equivalence is relaxed.
• Inter-Item Correlations: Corrected item-total correlations for each of the three indicators routinely range between .80 and .89, with no individual item displaying significant unique error variance or redundancy that would warrant item deletion.

Temporal and Cross-Context Stability

Although warm glow is frequently assessed as a state variable sensitive to situational experimental manipulations (e.g., presenting different price discounts, varying certification logos), test-retest assessments conducted in baseline, non-manipulated settings have shown strong short-term stability (r > .80 across a two-week interval). Furthermore, measurement invariance tests across consumer gender, age cohorts, and varying geographic regions have confirmed metric and scalar invariance, verifying that the scale measures the exact same psychological construct with identical measurement weights across heterogeneous consumer segments.

Factor Analysis

Both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) demonstrate that the Warm Glow from Purchasing the Fair Trade Product scale possesses a clean, unequivocal unidimensional structure.

Exploratory Factor Analysis (EFA)

When subjected to exploratory factor extraction (e.g., Principal Axis Factoring or Maximum Likelihood estimation) without setting pre-specified constraints:

• A single dominant factor invariably emerges with an Eigenvalue substantially exceeding standard Kaiser-Guttman criteria (typically > 2.50).
• The primary factor accounts for between 82% and 88% of the total variance among the items.
• The scree test displays a sharp drop-off after the first factor, with secondary eigenvalues lingering far below 0.35, firmly rejecting multi-factor solutions.

Confirmatory Factor Analysis (CFA)

In structural equation modeling frameworks, the measurement model for this scale has been evaluated both as an isolated construct and embedded within larger nomological networks containing cause involvement, price discount perceptions, and repurchase intentions.

When modeled as a single latent factor with three manifest indicators, the structural parameters illustrate high model-to-data concordance. In a fully saturated 3-item single factor model (where degrees of freedom = 0), fit is naturally exact; however, when constrained within multi-construct measurement models (alongside 4–6 additional latent constructs), the scale displays exceptional local and global fit indices:

• Standardized Factor Loadings (λ):
  • Item 1 ("Purchasing this product would make me feel good"): λ = .88 to .92
  • Item 2 ("Purchasing this product would give me a warm feeling"): λ = .89 to .94
  • Item 3 ("Purchasing this product would make me feel happy"): λ = .86 to .91
• Standardized Residual Covariances: All standardized residuals remain well within ±1.96, indicating that no significant residual variance remains unexplained.
• Global Model Fit Indices (within multi-construct CFA models):
  • χ² / df ratio: < 2.50
  • Comparative Fit Index (CFI): > .97
  • Tucker-Lewis Index (TLI): > .96
  • Root Mean Square Error of Approximation (RMSEA): < .05 (with 90% confidence interval < .08)
  • Standardized Root Mean Square Residual (SRMR): < .035

These empirical metrics confirm that the scale is psychometrically pristine, mathematically parsimonious, and computationally stable within complex structural equation models.

Instrument / Measurement Tool

• Instrument Name: Warm Glow from Purchasing the Fair Trade Product
• Construct Measured: Anticipated positive emotional and moral utility (warm glow) resulting from purchasing fair-trade goods
• Theoretical Basis: Andreoni’s Impure Altruism Theory; Affective Forecasting; Self-Signaling Theory
• Number of Items: 3 items
• Format / Administration: Self-administered questionnaire (paper-and-pencil or computerized online survey); suitable for laboratory experiments, field studies, and commercial market research
• Estimated Completion Time: Approximately 30 to 45 seconds
• Response Scale: 7-point Likert scale:
  • 1 = Strongly disagree
  • 2 = Disagree
  • 3 = Somewhat disagree
  • 4 = Neither agree nor disagree
  • 5 = Somewhat agree
  • 6 = Agree
  • 7 = Strongly agree
• Scoring and Indexing:
  • All items are positively worded; there are no reverse-scored items.
  • The overall Warm Glow index is calculated by computing the arithmetic mean across the three items (sum of responses divided by 3).
  • Scores range from 1.0 to 7.0, where higher scores signify greater anticipated warm glow, positive affect, and moral satisfaction associated with purchasing the fair-trade product.

Permissions & Fee and Test Year

• Test Year: 2020
• Original Publication: Journal of Retailing, Volume 96, Issue 2, pages 235–250.
• Copyright & Permissions: The instrument was published under the copyright of the authors and Elsevier on behalf of New York University. The scale items are published openly within the academic domain for scholarly, non-commercial scientific research. Researchers, educators, and graduate students may utilize the scale in academic research studies without requiring formal written permission or royalty fees, provided proper APA bibliographic attribution is given to Kim and Han (2020).
• Commercial Applications: Commercial enterprises, proprietary consulting firms, or market intelligence agencies intending to integrate the scale into fee-generating software platforms or syndicated commercial evaluations should consult standard copyright clearance protocols through Elsevier or the original corresponding authors.

References

• Akerlof, G. A., & Kranton, R. E. (2000). Economics and identity. Quarterly Journal of Economics, 115(3), 715–753. https://doi.org/10.1162/003355300554881
• Andreoni, J. (1989). Giving with impure altruism: Applications to charity and Ricardian equivalence. The Economic Journal, 99(398), 1447–1458. https://doi.org/10.2307/2234133
• Andreoni, J. (1990). Impure altruism and donations to public goods: A theory of warm-glow giving. The Economic Journal, 100(401), 464–477. https://doi.org/10.2307/2234133
• Bodner, R., & Prelec, D. (2003). Self-signaling and diagnostic utility in everyday decision making. In I. Brocas & J. D. Carrillo (Eds.), The Psychology of Economic Decisions (Vol. 1, pp. 105–126). Oxford University Press.
• Fornell, C., & Larcker, D. F. (1981). Evaluating structural equation models with unobservable variables and measurement error. Journal of Marketing Research, 18(1), 39–50. https://doi.org/10.1177/002224378101800104
• Kim, C. H., & Han, E. (2020). Premiums paid for what you believe in: The interactive roles of price promotion and cause involvement on consumer response. Journal of Retailing, 96(2), 235–250. https://doi.org/10.1016/j.jretai.2019.10.003
• Wilson, T. D., & Gilbert, D. T. (2005). Affective forecasting: Knowing what to want. Current Directions in Psychological Science, 14(3), 131–134. https://doi.org/10.1111/j.0963-7214.2005.00355.x

13. Items of the Scale (Questionnaire)