“Cashback for Positive Reviews”: Boon or Bane? An Empirical Study on the Impact of Negative Emotions in Review Manipulation on Evaluation Behavior

1. Introduction

The expansion of e-commerce has generated unprecedented opportunities for platform economies and their merchants while providing consumers with a broader and more convenient range of online choices. In online transactions, reviews have become a crucial channel for consumers to access product information and assess overall quality [1]. Online reviews play a vital role in alleviating information asymmetry and reducing quality uncertainties. As a result, they have become an indispensable reference for consumers’ online purchasing decisions [2]. Studies have indicated that more than 86% of consumers consult online reviews when shopping online, 80% of purchase decisions are influenced by them [3], and 93% of online shoppers spend over one minute reading reviews before making a decision (Local Consumer Review Survey, 2019). The specific functions of online reviews lie in consumers’ preliminary understanding of products and their initial assessment of merchants and purchased goods. Research has demonstrated that consumers use reviews to acquire additional information, which directly shapes their purchase intentions [4]. Concurrently, positive cues embedded in online reviews can facilitate transactions and promote product sales [5]. Evidence suggests that each one-star increase in average ratings can enhance sellers’ revenues by 5–9% [6], whereas negative reviews damage merchant reputation and suppress sales growth [7]. Therefore, online reviews serve not only as a channel for product information but also as a critical factor when formulating marketing strategies.

Online reviews are regarded as a resource, and platforms or merchants often pursue integrated management of favorable reviews to build their reputation and generate revenue [8]. Consequently, in pursuit of short-term gains, some merchants induce or manipulate consumers into engaging in unfair review practices through material incentives. Typical examples include “gift-for-praise” or “cashback for positive reviews” schemes (Figure 1). In such cases, merchants or platforms enclose cashback cards with purchased products to entice consumers to provide biased reviews. When purchases are driven by a merchant’s high rating or favorable comments, the sudden discovery of a cashback card undermines trust in those reviews. Even consumers not directly influenced by prior ratings often hesitate to post reviews after encountering such tactics, fearing that their comments might mislead potential buyers.

The manipulation of positive reviews by merchants or platforms has seriously compromised the fairness of the online review ecosystem, contributing to the proliferation of false reviews across all platforms. Existing studies on false reviews have explored issues such as publication causes [9], detection methods [10], and the influence of review content [11]. However, the negative consequences of review manipulation are significant. Practices such as hiring online trolls, fabricating transactions, and inflating credit ratings have distorted fair competition on e-commerce platforms. Moreover, consumers posting misleading or false reviews in exchange for rewards erodes the credibility of online evaluation [12]. When such manipulations are exposed, they elicit strong negative consumer sentiments. Although existing literature has examined the antecedents, identification, and consequences of fake reviews, research has primarily focused on the effects of informational attributes of fake reviews on consumers. However, a notable gap remains in understanding how specific antecedent stimuli—such as proactive manipulative behaviors by merchants (e.g., “cashback for positive reviews”)—systematically trigger consumers’ negative emotions and subsequently influence their review willingness and behaviors.

Therefore, this study focuses on the “cashback for positive reviews” behavior initiated by merchants, aiming to examine the influence mechanism through which negative emotions in review manipulation affect consumers’ psychological contract breach and review behaviors, thereby bridging the research gap regarding manipulative practices such as “cashback for positive reviews.” Furthermore, when consumers make purchase decisions based on platform review information, an implicit psychological contract regarding review authenticity exists between consumers and merchants. Merchants’ proactive use of “cashback for positive reviews” undermines the valence mechanism of online reviews. Therefore, drawing on the Stimulus-Organism-Response (S-O-R) theory, this study aims to systematically explain the theoretical mechanism through which positive review manipulation practices undermine the implicit psychological contract characterized by fair exchange and trust between consumers and merchants, thereby influencing consumers’ review behaviors. Based on the Stimulus–Organism–Response (S-O-R) paradigm, this study regarded the negative emotions induced by positive review manipulation as the environmental stimulus (S), conceptualized the psychological contract breach as the organismic state (O), and defined consumers’ review behavior as the organismic response (R). On this basis, a path model was proposed to link negative emotions generated by exposure to review manipulation with consumers’ evaluation behavior, and the mediating role of psychological contract breach within this S-O-R chain was examined. Furthermore, given consumer heterogeneity, responses to positive review manipulation may vary. This study also explored the moderating effect of consumers’ cognitive dissonance on the model pathway. These conclusions provide critical theoretical, practical, and managerial insights for the sustainable development of e-commerce and the establishment of a trustworthy online review system.

2. Literature Review

2.1. Negative Emotions Elicited by Positive Review Manipulation

Online reviews play a critical role in online shopping platforms, serving as a primary reference for consumers’ decision-making and purchasing behaviors [13]. Consequently, many merchants fabricate fake reviews to increase sales and rankings, thereby misleading consumers [14]. Such practices not only attract attention but also significantly elevate product clicks and purchase conversion rates [15]. Therefore, driven by profit motives, the widespread manipulation of reviews by platforms or merchants to fabricate favorable ratings has become a pervasive phenomenon [16]. Research has shown that false reviews can reduce the credibility of online comments [17], leading consumers to feel deceived and dissatisfied [18]. Because consumers typically rely on reviews to judge product or service quality, manipulated evaluations increase purchasing risks. When merchants conceal negative feedback through positive review manipulation, consumers who perceive exaggerated or inconsistent ratings experience heightened negative emotions [8].

Motivated by commercial gains, online merchants have strong incentives to manipulate positive reviews [19]. Despite existing research on review manipulation, studies focusing specifically on the negative emotions that can be elicited and their subsequent influence on consumer behavior remain limited. This study defines practices such as “cashback for positive reviews”—where merchants intentionally manipulate consumers into posting positive reviews—as positive review manipulation. As a non-transparent commercial practice contrary to fairness principle, positive review manipulation serves as a significant external negative stimulus (S) in consumers’ shopping experience, potentially triggering a series of negative psychological and behavioral responses among consumers. The focus of this study on negative emotions triggered by positive review manipulation is justified by the fact that this practice directly undermines the credibility of online reviews and consumers’ right to truthful information, which also constitutes a pressing practical issue requiring resolution in the current e-commerce sector. Building on this gap, the present study categorized negative emotions triggered by manipulation into three dimensions: disappointment, anger, and regret, and examined their varying intensities in shaping consumer responses. Disappointment reflects dissatisfaction with manipulated reviews, anger denotes aversion to such practices, and regret represents remorse for purchase decisions made based on misleading information.

2.2. Psychological Contract Breakdown Caused by Manipulation of Positive Reviews

Consumers often interpret high ratings as a signal that merchants have fulfilled their promises, assuming that the products or services will match their evaluations. This perception prompts the formation of a psychological contract based on a “transactional-relationship”. Thus, online positive reviews play a pivotal role in purchase decisions [20], and products or services with high ratings not only attract greater attention but also significantly increase purchase intentions [21]. However, the emergence of manipulated reviews undermines the trust relationship built upon review valence between consumers and merchants or platforms, leading to the rupture of this psychological contract.

A psychological contract breach is defined as an individual’s perception that the other party has failed to honor the reciprocal promises associated with his or her contributions [22]. More specifically, it refers to consumers’ belief that the seller has reneged on its obligations or duties [23]. In e-commerce settings, high ratings and favorable comments are intrinsically tied to the formation of psychological contracts. Once consumers detect that these evaluations have been artificially engineered, the goodwill or trust established through online reviews collapses, resulting in a psychological contract breach. When consumers encounter situations in which merchants request reviews in exchange for cash back, they tend to question the credibility of the evaluation content, thereby developing dissatisfaction and resistance towards merchants or platforms. Therefore, negative emotions constitute the direct emotional experience preceding psychological contract breach and further motivate consumers’ subsequent behavioral tendencies. Psychological contract breach is integrated into the Organism (O) process because it functions as a critical intermediary mechanism connecting cognitive evaluation and behavioral response, thereby enhancing the explanatory power for consumers’ behavioral motivations.

Consumers’ perceptions of manipulative practices, such as “cashback for positive reviews”, vary, and the negative emotions resulting from such practices differ in their impact on psychological contract breakdown. Different forms of breakdown consequently influence consumers’ evaluation behaviors in distinct ways. Accordingly, this study classified the psychological contract breakdown into transactional and relational dimensions and examined their respective effects on consumers’ evaluation behavior, as well as the mediating role of psychological contract breach between negative emotions and evaluation behavior.

2.3. Consumers’ Evaluation Behavior

Online reviews represent consumers’ public evaluations of a product or service’s attributes or quality after purchase [24]. Review-writing behavior can be affected by multiple factors, including cultural differences [25], perceived power and incentives [26], retaliatory motives [27], as well as utilitarian orientations and hedonic attitudes [28]. After extreme shopping experiences, consumers are more inclined to share their experiences online [29]. Consequently, they are more willing to post authentic evaluations in a fair and transparent review environment.

The practice of “cashback for positive reviews” serves as an incentive but simultaneously raises suspicions of coercion, pushing consumers into passive praise. When shoppers encounter such manipulation, they question the authenticity of existing reviews, creating a discrepancy between pre-purchase expectations and actual shopping experiences. Therefore, tactics such as “cashback for positive reviews” often backfire. Even if consumers initially comply, persistent coercion erodes their trust in the overall review system. On this basis, the present study categorized consumers’ evaluation behavior(R) into willingness to provide positive reviews and overall store ratings and empirically tested how coercive “cash-for-praise” schemes could suppress both dimensions, offering managerial insights for merchants and platforms.

2.4. Cognitive Dissonance

Cognitive dissonance refers to a negative psychological state that arises when an individual’s behavior is inconsistent with their internal cognitions or beliefs. It is pervasive in the context of contradictions and conflicts [30]. To mitigate this discomfort, individuals adjust their cognitions by changing, adding, or reducing their beliefs [31]. In the domain of consumer behavior, cognitive dissonance can generate adverse emotional reactions, such as unease, confusion, anxiety, and regret [32], and further induce negative actions, including purchase cancellations or reduced willingness to repurchase [33]. When consumers make purchasing decisions based on online reviews but subsequently encounter manipulative practices such as “rewarding positive reviews”, the psychological contract previously established may be disrupted. This breach further influences the evaluation behavior. In summary, cognitive dissonance may act as a moderating variable that shapes the relationship between consumers’ negative emotions and their evaluation behavior.

Table 1. Summary about prior findings on key concepts.

Concept	Author	Background	Theoretical/methods: background.	Strains and outcomes
Comment manipulation	Li et al. [34]	E-commerce platform	PAD emotion theory	Identification of advertising and rebate fake positive reviews
	Li et al. [35]	E-commerce websites and review sites	Mathematical modeling	Spam review detection
	Hu & Liu [36]	Amazon platform and noble Amazon	Mathematical modeling	Fraud detection in online consumer reviews
	Guo [37]	E-commerce platforms	Overview	The Impact of positive review cashback on the E-commerce online shopping market
	Guan et al. [8]	E-commerce platforms, tourism sector	SOR theory	Spam reviews, negative emotions, desire for revenge, avoidance tendency
	Chen et al. [38]	Homestay industry	Empirical analysis	Newly launched merchants, motives for manipulating online reviews
Psychological contract breakdown	Su et al. [39]	Customer service failure	Psychological contract theory and cognitive appraisal theory of emotion	Sense of betrayal anger, psychological contract breach
	Malhotra et al. [40]	Online retail	SOR theory	Trust, satisfaction, and repeat Usage intention/behavior
Cognitive dissonance	Shahin Sharifi & Rahim Esfidani [32]	Customer relationship management	SOR theory	Satisfaction and loyalty
	Li et al. [41]	Livestream shopping	Cognitive dissonance theory	Influencer traits、repurchase intention

Table 1. Summary about prior findings on key concepts.

Concept	Author	Background	Theoretical/methods: background.	Strains and outcomes
Comment manipulation	Li et al. [34]	E-commerce platform	PAD emotion theory	Identification of advertising and rebate fake positive reviews
	Li et al. [35]	E-commerce websites and review sites	Mathematical modeling	Spam review detection
	Hu & Liu [36]	Amazon platform and noble Amazon	Mathematical modeling	Fraud detection in online consumer reviews
	Guo [37]	E-commerce platforms	Overview	The Impact of positive review cashback on the E-commerce online shopping market
	Guan et al. [8]	E-commerce platforms, tourism sector	SOR theory	Spam reviews, negative emotions, desire for revenge, avoidance tendency
	Chen et al. [38]	Homestay industry	Empirical analysis	Newly launched merchants, motives for manipulating online reviews
Psychological contract breakdown	Su et al. [39]	Customer service failure	Psychological contract theory and cognitive appraisal theory of emotion	Sense of betrayal anger, psychological contract breach
	Malhotra et al. [40]	Online retail	SOR theory	Trust, satisfaction, and repeat Usage intention/behavior
Cognitive dissonance	Shahin Sharifi & Rahim Esfidani [32]	Customer relationship management	SOR theory	Satisfaction and loyalty
	Li et al. [41]	Livestream shopping	Cognitive dissonance theory	Influencer traits、repurchase intention

3. Research Models and Hypotheses

3.1. Research Models

Based on the S-O-R framework, this study implemented a theoretical model in which negative emotions (disappointment, anger, and regret) generated during positive review manipulation served as the independent variable (S). Psychological contract breach (transactional breach and relational breach) is treated as the mediating variable (O), while consumers’ evaluation behavior (willingness to provide positive reviews and store evaluation) constitutes the dependent variable (R). Additionally, consumer cognitive dissonance was incorporated as a moderating variable, and its moderating effect was examined. The research model is illustrated in Figure 2.

Based on the S-O-R framework, this study implemented a theoretical model in which negative emotions (disappointment, anger, and regret) generated during positive review manipulation served as the independent variable (S). Psychological contract breach (transactional breach and relational breach) is treated as the mediating variable (O), while consumers’ evaluation behavior (willingness to provide positive reviews and store evaluation) constitutes the dependent variable (R). Additionally, consumer cognitive dissonance was incorporated as a moderating variable, and its moderating effect was examined. The research model is illustrated in Figure 2.

3.2. Research Hypotheses

3.2.1. Relationship Between Negative Emotions and Psychological Contract Breach

Social exchange theory suggests that individuals strive to maximize benefits in exchanges, and when the balance between inputs and outcomes is disrupted, a stress response is triggered [42]. A psychological contract breach occurs when individuals perceive the organization to have acted in bad faith, often accompanied by emotions such as betrayal, anger, and disappointment [43]. In online shopping contexts, where consumers cannot directly verify product quality, an implicit contractual relationship with the merchant is often established through online reviews [44]. However, the manipulation of positive reviews undermines the authenticity of these evaluations and prompts negative emotions such as disappointment, anger, and regret, which subsequently causes the breakdown of the psychological contract.

Research has reported that negative emotions, such as disappointment and regret, are closely linked to psychological contract violations [45]. When individuals perceive betrayal, the accumulation of negative emotions precipitates a contract breach [46]. Therefore, in online shopping, consumers’ trust and emotional investment in merchants incline them to believe in the authenticity of reviews. Once manipulation triggers a crisis of trust, negative emotions become the primary driver of psychological contract breaches, thereby shaping consumers’ evaluative attitudes and behaviors towards merchants or brands. Disappointment, anger, and regret, as varying degrees of negative emotions, may exert differential effects on different forms of psychological contract breach. Accordingly, the following hypotheses are proposed.

H1 

: Negative emotions (H1a disappointment, H1b anger, and H1c regret) positively influence the transactional psychological contract breach.

H2: 

Negative emotions (H2a disappointment, H2b anger, and H2c regret) positively influence the relational psychological contract breach.

3.2.2. Relationship Between Psychological Contract Breach and Evaluation Behavior

Social exchange theory indicates that the greater the mutual obligation between exchange partners, the more stable the relationship. A psychological contract breach represents a typical case of social exchange imbalance [47]. According to the psychological contract violation–behavioral response model, different types of psychological contracts exert distinct influences on individual behavior; once individuals perceive a breach, they are inclined to respond negatively [48]. After a psychological contract is broken, consumers often display adverse coping behaviors such as complaints, silence, or even destructive actions [49]. Research has indicated that psychological contract breaches can diminish consumers’ reuse intentions and recommendation behavior [40]. In particular, transactional psychological contracts based on short-term benefits, when breached, may reduce purchase and recommendation behaviors but exert limited influence on a merchant’s long-term reputation [46]. Once the relational psychological contract is broken, consumers’ trust, commitment, and loyalty to the merchant are adversely affected [50].

In online shopping, evaluation behavior is primarily reflected in consumers’ willingness to provide positive reviews and store ratings. When positive review manipulation occurs, the psychological contract with the merchant and platform is breached, leading to a decline in consumers’ willingness to leave positive reviews and their store evaluation behavior. In other words, the negative emotions triggered by manipulative practices can cause psychological contract breaches, and consumers also fear that their reviews may mislead potential buyers, further reducing their willingness to post. Therefore, the following hypothesis is proposed:

H3: 

Transactional psychological contract breach negatively affects evaluation behavior (H3a: willingness to give positive reviews; H3b: store rating).

H4: 

Relational psychological contract breach negatively affects evaluation behavior (H4a: willingness to give positive reviews; H4b: store rating).

3.2.3. Regulatory Role of Cognitive Dissonance

Because online purchasing does not provide direct experience of product quality, consumers rely heavily on online reviews when making decisions [20]. However, the manipulation of positive reviews can widen the gap between consumers’ pre-purchase expectations and post-purchase outcomes, thereby triggering stronger negative feelings. Research has indicated that false information can induce cognitive dissonance, prompting impulsive decisions [51], while post-purchase dissonance often results in negative behaviors, such as product returns [52], as highly dissonant consumers attempt to restore their internal balance [53]. In response to inconsistent information, cognitive dissonance heightens consumers’ sensitivity to merchant dishonesty and promotes divergent behavioral reactions. Specifically, the practice of “cashback for positive reviews” introduces heterogeneous information that can generate cognitive dissonance. Consumers may worry that positive review content will mislead future buyers, thereby reducing their own evaluation behavior. Therefore, this study suggests that consumers with higher levels of cognitive dissonance may experience stronger negative emotions, which may intensify their perception of a psychological contract breach and influence subsequent review behavior. Based on this reasoning, the following hypothesis is proposed:

H5: 

Cognitive dissonance moderates the sequential path from negative emotions to psychological contract breach and subsequently to consumer review behavior.

4. Discussion

4.1. Scale Design and Data Sources

Before finalizing the scales, a comprehensive pre-survey was performed. This study focused on the shopping scenario of “cashback for positive reviews” in online purchasing, and respondents were limited to consumers who both understood and had personally experienced this practice, thereby enhancing ecological validity [54]. To strengthen the generalizability and applicability of the findings, purposive sampling was adopted. Its primary advantage was the precise alignment between research objectives and participant selection [55], thereby enhancing methodological rigor and improving the credibility of data and results [56]. Because purposive sampling requires a certain level of organization and a clearly defined scope, a pre-test and screening questions were incorporated into the formal survey to ensure accuracy and relevance of participants. Example screening questions included: “Have you ever encountered cashback for positive reviews?” “Have you participated in cashback for positive reviews?” “Do you consider cashback for positive reviews reasonable?” After completing the investigation, each participant received a reward of 6 CNY.

The questionnaire comprised four core constructs: negative emotions, psychological contract breach, review behavior, and cognitive dissonance. To ensure consistency with the research context, all scales were adapted from relevant studies in the Chinese context and subjected to minor revisions based on the specific research context. Response was measured on a seven-point Likert scale (1 = strongly disagree to 7 = strongly agree). Negative emotions, including disappointment, anger, and regret, were adapted from [8]. Example items included: “I am deeply disappointed by the cashback-for-positive-review practice,” “I am angry about the brand’s cashback-for-positive-review behavior,” and “After encountering cashback for positive reviews, I regret choosing this merchant” [8]. Transactional and relational psychological contract breaches were measured using four items adapted from [47]. Example items include: “I believe merchants have not dealt with consumers honestly” and “Merchants do not respect and value consumers.” Willingness to provide positive reviews was measured using two items [1], such as “Whether one is willing to provide a positive review.” Store evaluation was assessed with three items [1], including “Whether one perceives the store as well managed.” Cognitive dissonance was measured with three items [57], including “I am unsure whether posting positive review information is the right thing to do.”

A formal survey was conducted from March 2024 to December 2024 using the Chinese professional online survey platform Wenjuanxing (https://www.wjx.cn/). A total of 530 questionnaires were collected. After excluding those who failed the screening criteria, 460 valid responses were retained, resulting in an effective response rate of 86.79%. Methodological guidelines suggest that the minimum ratio of sample size to questionnaire items should be 5:1. In this study, the ratio reached 13.9:1, meeting the requirement [58]. The descriptive statistics of the samples are presented in Table 2.

4.2. Data Reliability and Validity Tests

Validity and reliability were assessed using SPSS 26.0 and AMOS 24.0, based on Cronbach’s alpha coefficient, the combined reliability (CR) value, and the average variance extracted (AVE) [59]. The results indicated that Cronbach’s alpha coefficients exceeded 0.700, the AVE values were higher than 0.500, and the CR values surpassed 0.800, demonstrating the good reliability of the proposed model (Table 3).

The convergent validity of the measurement model was examined using confirmatory factor analysis. The fit indices of the measurement model indicated a good model fit, with the results indicating X2/df = 1.561, IFI = 0.990, TLI = 0.988, and CFI = 0.990. The differential validity was confirmed, as the square roots of the AVE values for each construct were higher than the absolute values of the corresponding correlation coefficients, indicating an acceptable level of validity [60]. The detailed results are listed in Table 4.

4.3. Hypothesis Tests

Prior to hypothesis testing, a goodness-of-fit test was conducted on the structural equation model. The results showed χ2/df = 2.779, IFI = 0.974, TLI = 0.969, CFI = 0.974, AGFI = 0.868. These indices were close to the thresholds, indicating that the model was appropriate for validating hypothesized relationships [60]. The hypothesized pathways were estimated using standardized coefficients. The results are shown in Table 5.

Empirical analysis demonstrated that consumers’ negative emotions significantly and positively influenced the transactional psychological contract breach, thereby supporting Hypothesis H1. Although transactional psychological contracts could be essentially based on mutually beneficial exchanges or one-time consumption, these relationships relied to some extent on trust in online reviews. When consumers encounter review manipulation by merchants or platforms, the resulting negative emotions intensify the breach of transactional psychological contracts. Thus, cashback for positive reviews could fuel negative emotions and accelerate the transactional-contract breakdown.

In addition, the results indicated that consumers’ negative emotions significantly affected relational psychological contract breaches, supporting Hypothesis H2. These findings confirm that positive review manipulation not only triggers transactional contract breaches but also directly precipitates the rupture of relational contracts. Negative emotions diminish goodwill and loyalty towards merchants, thereby weakening long-term buyer-seller relationships. Since online reviews can act as a critical bridge of communication, their authenticity and reliability may play a crucial role. However, merchants’ manipulation of reviews not only provoked negative consumer emotions but also undermined review credibility. This dual effect illustrates the destructive impact of manipulation on consumers’ psychological contracts and highlights the importance of improved review management by platforms and merchants.

Regarding the relationship between psychological contract breach and consumers’ evaluation behavior, transactional contract breach had a significant negative impact on both willingness to provide positive reviews and store ratings, thereby supporting H3. Relational contract breach exerted even stronger negative effects on willingness to post reviews and store ratings, thus supporting H4. Previous research has shown that different forms of psychological contracts can yield distinct behavioral responses. This study confirmed that in the context of positive review manipulation, breaches of both transactional and relational contracts reduced consumers’ willingness to leave favorable reviews and lowered their evaluation of stores. Moreover, the effect of relational contract breach is more profound than that of transactional breach, indicating that long-term trust and commitment are more deeply damaged by review manipulation.

4.4. Testing the Mediating Effect of Psychological Contract Breach

The mediating effect was examined using a bias-corrected bootstrap procedure (5,000 resamples). Significance was determined by whether the 95% confidence interval excluded zero. The full results are reported in Table 6.

The 95% bias-corrected and percentile confidence intervals for each indirect path excluded zero, confirming that all mediating effects were statistically significant [61]. The findings demonstrated that both transactional and relational psychological contract breaches fully mediated the impact of positive review manipulation on consumers’ negative emotions and subsequent evaluation behaviors. In other words, when consumers encountered manipulated positive reviews, the resulting negative emotions, including disappointment, anger, and regret, led to breaches of the psychological contract with the merchant or platform, which diminished their willingness to provide positive reviews and engage in evaluation behaviors.

4.5. Testing the Moderating Role of Consumer Cognitive Dissonance

The moderating role of consumer cognitive dissonance in the hypothesized path relationships was also investigated. Using the median score of the cognitive dissonance scale as the cutoff, respondents were divided into low (N=224) and high dissonance (N = 236) groups. A structural equation model was then applied to compare the two groups [62], with the results reported in Table 7

In the relationship between negative emotions and consumer psychological contract breach, disappointment significantly increased the transactional psychological contract breach, with the effect being stronger among consumers with low cognitive dissonance. However, the effect of disappointment on the relational psychological contract breach did not reach the significance threshold, indicating that the group comparison lacked statistical validity. For anger, the effect on the transactional breach was stronger among high-cognitive-dissonance consumers. In contrast, anger did not significantly affect relational breaches across groups. Furthermore, regret significantly intensified the psychological contract breach, with the effect being stronger among high-cognitive-dissonance consumers for both transactional and relational breaches.

Regarding the relationship between psychological contract breach and consumers’ evaluation behaviors, relational psychological breach exerted a stronger negative effect on store rating and willingness to leave positive reviews among high-cognitive-dissonance consumers. For transactional breach, the critical ratios for both outcomes failed to reach significance, rendering the between-group comparison statistically invalid. Thus, H5 was partially supported.

In summary, for consumers with low cognitive dissonance, disappointment triggered by review manipulation was more likely to cause a transactional psychological contract breach, whereas for those with high cognitive dissonance, anger and regret induced by review manipulation were more likely to lead to a transactional psychological contract breach. Among high-dissonance consumers, regret was also more likely to precipitate a relational breach of the psychological contract. Furthermore, once the relational psychological contract was violated, high-cognitive-dissonance consumers exhibited an even stronger negative impact on both their willingness to provide positive reviews and store evaluations. Therefore, cognitive dissonance emerged as a critical construct in the context of review manipulation, underscoring its significant role in influencing psychological contract breaches and subsequent evaluative behaviors.

5. Conclusions and Management Implications

5.1. Conclusions

Based on the S-O-R theory, this study verified that negative emotions generated by positive review manipulation led to the breakdown of psychological contracts and further reduced consumers’ evaluation behavior. Simultaneously, it confirmed the moderating role of consumer cognitive dissonance in the model and revealed the mechanism underlying the interaction between consumers’ negative emotions and evaluative behaviors in the context of positive review manipulation. The main conclusions are as follows.

First, the results clarified that negative emotions induced by cashback for positive reviews triggered a breach of consumers’ psychological contracts. This finding deepens our understanding of how review manipulation, as perceived by consumers, can influence purchase decisions [2]. This study enriches the literature on the theoretical link between negative emotions and psychological contract breach in the context of review manipulation practices (e.g., merchant-initiated “cashback for positive reviews” tactics), providing valuable theoretical insights for platforms and merchants to optimize online review management. Simultaneously, it offers a new perspective for interdisciplinary research integrating consumer behavior and psychological contract theories. The manipulation of positive reviews by merchants not only evoked negative emotions among consumers but also undermined the effectiveness of online reviews, eroding their original trust value and becoming a significant factor in review system failure. This finding highlights the dual destructive effect of positive review manipulation on consumers’ psychological contracts. From a practical perspective, the results provide important managerial implications for e-commerce platforms and merchants, suggesting that they should strengthen the supervision of review mechanisms and enhance service quality and transparency, thereby reducing the occurrence of positive review manipulation. Such measures would help maintain consumer trust and promote sustainable platform development.

Second, in the context of cashback for positive reviews, the breakdown of psychological contracts exerted a negative influence on consumers’ evaluative behaviors. Specifically, the detrimental effect of a relational psychological contract breach on consumer review behavior was considerably stronger than that of a transactional psychological contract breach. This suggested that although transactional contract violations could undermine evaluative behavior, the long-term and far-reaching consequences of relational contract breakdown were more pronounced. This finding is consistent with prior evidence showing that cashback for positive reviews” erodes shopping experiences, undermines the perceived authenticity of reviews, and ultimately depresses purchase intention [63]. From a managerial perspective, platforms should strengthen the oversight of merchants’ manipulation of reviews, enhance transparency and fairness in evaluation systems, and reduce consumers’ perception of manipulative practices. Such measures would diminish the likelihood of a psychological contract breach, preserve the stability of the psychological contract, and consequently increase consumers’ willingness to provide evaluations, thereby amplifying the positive value of online reviews.

Finally, cognitive dissonance emerged as a critical factor that triggered psychological contract breaches and diminished consumers’ willingness to review. Although “cash-for-positive-review” schemes fell into a legal gray area and were constrained by regulations and platform rules, competitive pressures could drive certain merchants and platforms to adopt these incentives. While such practices may temporarily stimulate purchasing decisions [11], they can create psychological imbalances for consumers endorsing the product, leading to heightened cognitive dissonance. As cognitive dissonance intensified, psychological contracts were more likely to collapse, and the willingness to provide evaluations declined. This conclusion further verified that cognitive dissonance as a manifestation of psychological imbalance significantly exacerbated the breakdown of psychological contracts and magnified the reduction of evaluative behaviors in the context of “cash-for-positive-review.” Specifically, higher levels of cognitive dissonance were associated with more severe psychological contract breaches, thereby amplifying negative effects on evaluative behaviors.

This finding not only enriches the literature on the relationships among negative emotions, psychological contract breach, and review behavior in the context of manipulation but also offers theoretical guidance for platforms and merchants in managing consumer emotions and evaluation behaviors. From a practical perspective, e-commerce platforms and merchants should pay closer attention to psychological factors, such as cognitive dissonance. By optimizing evaluation mechanisms, improving service quality, and enhancing communication with consumers, they can reduce sensitivity to manipulative practices, thereby minimizing the adverse influence of negative emotions and cognitive dissonance on psychological contract stability and evaluative behavior.

5.2. Management Insights

This study delineates the pathway through which consumers’ negative emotions can influence psychological contract breach and review behavior in the context of cashback for positive reviews. It extends the theoretical boundary of research on online review valence and offers the following managerial implications for the sustainable development of e-commerce.

First, for platforms, strengthening supervision of the review mechanism is essential to improve authenticity and transparency of evaluation. Platforms should enhance the oversight of merchants’ manipulation of positive reviews by employing technological tools to identify and combat fake reviews, such as by detecting anomalous patterns via algorithms or implementing manual review systems. For example, platforms should establish clear boundaries and measures for manipulating positive reviews, explicitly list such practices as prohibited activities in platform rules, impose rating penalties on non-compliant merchants, attach risk warning labels to misleading reviews, and guide consumers to engage in rational and responsible review behavior. Simultaneously, platforms should enhance the visibility of review mechanisms by clearly presenting the source and authenticity of reviews, thereby mitigating potential consumers’ perception of manipulation, lowering the likelihood of negative emotions and psychological contract breaches, and reinforcing consumers’ trust in the platform.

Second, merchants should value the valence mechanism of online reviews and acknowledge the adverse consequences of incentivizing positive reviews. Online reviews function as informational signals via which merchants communicate product quality to consumers, with their effectiveness depending on authenticity and verifiability. Incentivized positive reviews distort the review generation mechanism via economic incentives, causing review signals to degenerate from those reflecting product quality into self-interest-driven signals, thereby precipitating a triple trust crisis encompassing the valence mechanism of online reviews, platform governance logic, and consumers’ trust expectations. Such behavior not only breaches consumers’ fundamental expectations pertaining to review authenticity but also entails the risk of undermining the psychological contract that exists between consumers and merchants. In the long term, merchants should discard the short-term mentality of pursuing traffic volume and transition to reputation management rooted in authentic quality, while adhering to the platform rule-centric evaluation valence mechanism. Only in this way can they foster a virtuous cycle characterized by authentic reputation, long-term trust, and performance growth in the digital marketplace, and realize the transformation from over-reliance on traffic to value-driven development.

Finally, regulatory efforts to curb cashback schemes for positive reviews are fundamentally intended to safeguard the information order in the digital economy. This entails not only curbing market irregularities stemming from short-term gains but also fostering a virtuous ecological cycle of “authentic reviews—consumer trust—merchant innovation”. In terms of responsibility allocation, a dual accountability mechanism should be established for merchants and platforms, with clear definition of platforms’ regulatory obligations to provide a robust basis for oversight. This regulatory process must achieve dual objectives: on the one hand, it needs to eliminate merchants’ short-term profit-driven incentives to distort consumer reviews via cashback through disciplinary mechanisms, thereby preventing false information from misleading consumer decisions and impairing the fair competition environment; on the other hand, it should focus more on fostering a virtuous ecological cycle of “authentic reviews—consumer trust—merchant innovation”: by ensuring the objectivity of review information, this consolidates the foundation for consumer decision-making, thereby incentivizing merchants to allocate resources to improving product and service quality instead of resorting to information manipulation to gain competitive advantages, and ultimately achieving dual enhancements in market operational efficiency and innovation vitality. In this process, constructing a dual accountability system that emphasizes merchants’ primary responsibility and platforms’ supervisory responsibility constitutes the core approach. This entails clarifying platforms’ governance obligations concerning the review ecosystem, establishing a synergistic mechanism involving “merchant self-regulation + platform heteronomy,” and providing institutional guarantees for the effective enforcement of regulatory measures.

5.3. Limitations

This study verifies the influence path of negative emotions triggered by positive review manipulation on consumers’ willingness to evaluate and expands the theoretical and practical scope of longitudinal research on online reviews. Nevertheless, several limitations remain that require further exploration in future studies. First, the survey respondents were restricted to individuals who had a certain understanding of “cash-for-praise” and had experienced it. However, some consumers may perceive cash-for-praise as “why not,” indicating a potential cognitive bias. Therefore, future studies should account for heterogeneous conclusions arising from consumers’ cognitive differences. Second, positive review manipulation is multifaceted, encompassing platforms or merchants hiring paid posters and engaging in fake-order brushing, as well as consumers issuing misleading or false reviews in exchange for rebates or gifts. This study focuses solely on the “cash-for-praise” scenario, thereby limiting its explanatory scope with respect to the full range of manipulation behaviors. Future research should differentiate between various forms of positive review manipulation to provide a more comprehensive understanding. Finally, because consumers differ in how they perceive “cashback for positive reviews,” this study incorporated cognitive dissonance as a moderator of the hypothesized paths. Although significant moderating effects were observed for some relationships, other control variables and consumer cognitive differences require further investigation.