Abstract: Unplanned purchase is very pervasive in daily life, which is characterized by the combination of cognition and affect. This study aimed at investigating the question of how to influence consumers’ unplanned purchase decision when they hesitate on whether to buy or not. Previous studies confirmed that prefactual thinking can affect consumers’ behaviors through signifying possible results of a certain behavior. Thus, we proposed that both anticipated regret and anticipated rejoice has the potential to enhance consumers’ unplanned purchase intention. The motivation theory, however, suggests that consumers with different regulatory focuses have different sensitiveness towards gains and losses. Based on that, we proposed that anticipated regret was more effective for prevention-focused consumers, while anticipated rejoice was more effective for promotion-focused consumers. Regarding the mechanism of the effect of prefactual thinking, we drew inspiration from justification theory and proposed that prefactual thinking influences consumers’ judgment of reasonableness of unplanned purchase, through which to influence their unplanned purchase intention.
This research contained two studies. Study 1 utilized quasi-experiment method with 136 subjects to examine the interactive effects of prefactual thinking and regulatory focus on unplanned purchase intention. In this study, we measured participants’ regulatory focuses and manipulated their prefactual thinking. We used paired t-test to examine the impact of anticipated regret and anticipated rejoice on the change of unplanned purchase intention, and used two-way ANOVA to analyze the interactive effects of prefactual thinking and regulatory focus on subjects’ final unplanned purchase intention and on their intention change. Study 2 was designed as an experiment with 218 subjects to examine the role of justification in the process. In this study, we manipulated both subjects’ regulatory focuses and their prefactual thinking. Like in Study 1, we utilized paired t-test to examine the impact of anticipated regret and anticipated rejoice on the change of unplanned purchase intention, and utilized t-test to examine the influence of prefactual thinking on subjects’ perceptions of gain-related reasons and loss-related reasons. The interactive effects of justification and regulatory focus were tested through regression analysis.
The results demonstrate that marketers can enhance consumers’ justification perception of the unplanned purchase by designing anticipated rejoice and anticipated regret impetus, through which to enhance their unplanned purchase intention. However, the results indicate that the effectiveness of prefactual thinking varies with consumers’ regulatory focus. Anticipated rejoice is more effective for promotion-focused consumers while anticipated regret is more effective for prevention-focused consumers. We also find that promotion-focused consumers place more emphasis on gain-related reasons when making unplanned purchase decisions, while prevention-focused consumers place more emphasis on loss-related reasons when making unplanned purchase decisions.
This study broads our understanding on consumer behavior by inquiring into unplanned purchase behavior, which is in the middle of impulsive purchase and planned purchase and characterized by combining both cognition and affect. Furthermore, it is the first to investigate the question of how to affect unplanned purchase behaviors. It can also have managerial implications. First, it reminds managers that consumers’ unplanned purchase can be influenced and managed by designing effective marketing tactics. In order to enhance unplanned purchase intention, retailing managers should encourage consumers to imagine the potential results of purchase or non-purchase. When designing marketing tactics, mangers should keep consumers’ characteristics in mind. They should encourage promotion-focused consumers to imagine the possible pleasure or rejoice of making purchase, and encourage prevention-focused consumers to imagine the possible pain or regret of making non-purchase.

Key words: unplanned purchase, prefactual thinking, regulatory focus, purchase justification