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How emotions affect unplanned buying behaviour: the role of valence and arousal

posted on 26.02.2017, 23:31 by Abedniya, Abed
Unplanned/impulse purchases form a considerable portion of grocery and retailing sales. Due to the economic importance of this phenomenon, retailers invest substantially in in-store marketing to encourage consumers to engage in this type of shopping; while public policy makers and consumer advocates seek to reduce it; and over the last few decades researchers have explored the potential factors associated with its occurrence. Prior research finds that unplanned buying is reactive behaviour and often involves an immediate action response to a stimulus. The stimuli can be internal (based on inner psychological states) or external (based on environmental cues) and can cause emotional responses which lead to different decisions and behaviours among consumers. While there has been extensive research into the nature and determinants of unplanned purchase behaviour, there is still little understanding of how emotional factors influence this behaviour. Drawing from emotion regulation theory, this research aims to investigate how consumers’ unplanned purchase behaviour is shaped by emotional components (valence and arousal) that occur in response to in-store stimuli. Also, the role of type of the planned product, in particular whether the product is predominantly hedonic or utilitarian is investigated. By including all these factors in one study, this research delivers advantages over preceding studies, which considered the effects of only one of the components of emotion at the time (either valence or arousal) on unplanned buying. The empirical part of the thesis consists of four scenario-based experiments conducted in a behavioural lab using over eight hundred participants in total. The experiments unobtrusively manipulated consumers’ emotional states through exposure to movie clips that form part of a shopping scenario. The scenarios allowed direct observation of the extent of unplanned buying. Findings in general show that consumers’ unplanned purchase behaviour depends on the specific combination of current levels of valence and arousal. The results of the first two experiments demonstrate that the effects of arousal and valence are interdependent and that neither can singly explain the unplanned buying behaviour process. This suggests that if participants are in a pleasant emotional state they display greater levels of unplanned buying when they are aroused than when they are not aroused, while the reverse holds when they feel unpleasant. The results of the second and third experiments replicate the findings from the earlier experiments and provide strong additional support for the prediction that consumers’ unplanned buying behaviour it a joint function of their current level of arousal and valence. Besides, the findings show that the effects of affect on consumer unplanned buying behaviour also depend on the type of planned item. The findings suggest that the interaction of valence and arousal is no longer significant when consumers had hedonic choices on their shopping list. In contrast, when they are in a pleasant emotional state with a utilitarian item in their shopping list, they are likely to purchase a greater number of unplanned products if they are aroused than when they are not aroused. Study four also shows the conceptual link between unplanned buying behaviour and consumers’ unhealthy consumption behaviour. Evidence from this experiment suggests that consumers who are more likely to engage in unplanned behaviour prefer unhealthy over healthy items. Besides, the results further demonstrate the robustness of the interaction effect of arousal and valence on consumers’ unplanned purchasing by testing the effect of arousal and valence on consumers’ unhealthy consumption choices. The insights gained by this research can help retailers, marketers and public policy makers to better understand how and why consumers buy unplanned items. The insights can help them to select marketing strategies inside the retail store that will persuade more customers to engage in unplanned buying behaviour. Conversely the results can help consumer advocates and regulators to better identify where consumers may need protection. In same line, given the potentially harmful consequence of unplanned/impulse buying behaviour, the findings of this research can help marketers, public policy or social marketing researchers to understand and identify the best way to reduce unhealthy unplanned consumption.


Campus location


Principal supervisor

Harmen Oppewal

Additional supervisor 1

Gerri Spassova

Year of Award


Department, School or Centre

Business. Marketing


Doctor of Philosophy

Degree Type



Faculty of Business and Economics