Mark Lett DOI 10.1007/s11002-011-9135-4
Building consumer self-control: The effect of self-control exercises on impulse buying urges Abdullah J. Sultan & Jeff Joireman & David E. Sprott
# Springer Science+Business Media, LLC 2011
Abstract In this research, the effects of self-control exercises on impulse buying urges are examined. Drawing on the strength model of self-control (Baumeister and Heatherton 1996, Psychological Inquiry 7:1–15), the present paper aims to shed light on impulsive buying by exploring the impact of enhancement of self-control as a result of repeated physical and cognitive self-control exercises over time. The findings showed that these self-control exercises reduced impulse buying urges. Directions for future research are discussed. Keywords Impulse buying . Self-control . Self-regulation . Ego depletion Impulsive buying has been estimated to account for over $4 billion in retail store sales (Mogelonsky 1998). Given its pervasiveness, researchers have been keen to identify the underlying causes of impulsive buying. One model that has recently been used to understand impulsive buying is the strength model of self-control (Baumeister and Heatherton 1996; Vohs and Faber 2007). Applied to impulsive buying, the strength model assumes that a consumer’s ability to control urges to engage in impulsive buying can (a) become temporarily depleted as a result of prior self-control efforts (a depletion effect) and (b) be built up over time through repeated self-control exercises (an exercise effect). The present research focuses on the latter by exploring whether simple physical and cognitive exercises, practiced over the course of 2 weeks, can reduce consumers’ urges and intentions to engage in impulsive buying.
A. J. Sultan (*) Department of Management and Marketing, Kuwait University, P.O. Box 5486, Safat 13055, Kuwait e-mail:
[email protected] J. Joireman : D. E. Sprott Department of Marketing, Washington State University, P.O. Box 644730, Pullman, WA 99164-4730, USA
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1 Theoretical background Rook (1987, p. 191) defines impulse buying as “a sudden, often powerful and persistent urge to buy something immediately” and suggests that impulsive buying is more emotional rather than rational, while Beatty and Ferrell (1998, p. 170) view impulse buying as “a sudden and immediate purchase with no pre-shopping intentions either to buy the specific product category or to fulfill a specific buying task.” This behavior occurs after experiencing an urge to buy and tends to be spontaneous (Beatty and Ferrell 1998). Our definition of impulse buying is aligned with those of these researchers. That is, we believe that impulse buying may occur after experiencing an urge to buy, without going through a deliberate thought process and weighing options carefully (cf. Dholakia et al. 2005). Whether one views impulsive buying as an urge or a behavior, research clearly indicates that there are many factors that trigger impulse buying. A central theme underlying much recent research on impulse buying is the concept of self-control (Baumeister 2002; Faber and Vohs 2004). Hoch and Loewenstein (1991) view consumer self-control as an ever-shifting conflict between desire and willpower (cf. Dholakia 2000; Metcalfe and Mischel 1999; Shiv and Fedorikhin 1999; Strack and Deutsch 2004). When the desire for a product surpasses consumers’ intentions to not make a purchase, impulse buying can occur. This suggests that two separate mechanisms are involved with impulsive buying, namely (1) the desire to buy and (2) the ability to exercise self-control over this urge. Self-control refers to one’s “ability to control or override one’s thoughts, emotions, urges, and behavior” (Gailliot et al. 2007, p. 325). A prominent view of self-control is the strength model (Baumeister and Heatherton 1996; Baumeister et al. 2000). This view recognizes the importance of stable individual differences in trait self-control and temporary fluctuations in state self-control. For example, research clearly supports the idea that self-control is a personality trait that remains fairly constant over one’s lifetime (e.g., Mischel et al. 1989; Tangney et al. 2004). Along these lines, researchers have linked lower levels of impulse buying to personality traits related to self-control, including conscientiousness (Verplanken and Herabadi 2001), consideration of future consequences (Joireman et al. 2005), and elaboration on potential outcomes (Nenkov et al. 2008). Other studies demonstrate that self-control is susceptible to temporary variations based on the situation. According to the strength model, this occurs because selfcontrol operates like a muscle: in the short run, self-regulatory resources can become consumed as a result of closely sequenced acts of self-control (just as a muscle can become immediately fatigued following physical exertion; an ego depletion effect); yet, over the long run, self-control can also be strengthened through repeated selfcontrol exercises (like a muscle can be strengthened over time through physical training; an exercise effect). 1.1 Depletion effects Ego depletion effects were first demonstrated by Muraven et al. (1998) who showed that when participants initially regulated their emotions or engaged in thought suppression, they subsequently evidenced reduced physical stamina, less persistence
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at unsolvable anagrams, and a weaker ability to regulate their emotions. In another paper, Baumeister et al. (1998) reported similar results using different depletion manipulations (eating radishes rather than cookies; engaging in attitude-inconsistent behavior; and completing a complex set of editing procedures) and different subsequent self-regulatory tasks (unsolvable puzzles and a test of passive responding). Building on these initial findings, many studies have supported the strength model, several of which bear directly on consumer behavior. For example, Vohs and Heatherton (2000) demonstrated that when chronic dieters first resisted a tempting array of snacks, or regulated their emotions, they later showed less persistence at unsolvable anagrams and ate more ice cream. Using dependent measures more closely aligned with impulsive buying, studies have shown that controlling negative emotions increases participation in lottery games (Bruyneel et al. 2009), and making repeated choices—shown to deplete regulatory resources (Vohs et al. 2008)— increases reliance on affective features of a product (Bruyneel et al. 2006). Other research has demonstrated that responding to initial requests in multiple-stage compliance techniques (foot-in-the-door) leads to self-regulatory depletion and subsequent compliance with charitable requests (Fennis et al. 2009). More directly relevant is recent research by Oaten and Cheng (2005) showing that academic stress (brought on by exams) is associated with significant increases in smoking, eating junk food, and impulsive spending, and by Vohs and Faber (2007) who demonstrated that participants whose self-regulatory resources had been experimentally depleted felt stronger urges to buy, were willing to spend more, and actually did spend more in unanticipated buying situations. 1.2 Exercise effects While most research on the strength model of self-control has focused on regulatory depletion, an important implication of the strength model is that capacity for selfcontrol can, like a muscle, grow stronger over time through repeated self-control exercises. In general, there are two ways in which self-regulatory strength could be improved: power (an increase in the simple baseline capacity) and stamina (a reduction in vulnerability to fatigue). A number of researchers have provided evidence that supports the ways in which this muscular strength can be increased. For example, Muraven et al. (1999) had participants perform one of three different types of self-control exercises over a 2-week period (i.e., improving posture, regulating emotion, or keeping a food diary). Results revealed that posture and food diary exercises improved self-control resources (physical stamina) following a thought-suppression task as compared to a control group. The emotion-regulation exercise, however, yielded results no different from the no-exercise control group, which may have been due to the fact that people often regulate emotions and hence an emotion-regulation exercise provided no additional benefit. A series of studies by Oaten and Cheng provided additional support for the hypothesis that repeated self-control exercises improve self-control over time. These studies focused on two outcome measures, including a visual tracking experiment under distraction (a measure of sustained attention), and a collection of selfregulatory behaviors (smoking, alcohol consumption, dietary habits, physical
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activity, and consumer behaviors). Oaten and Cheng (2006a) assigned students to a physical exercise condition or a waitlist control condition. Those in the exercise condition showed improvements on the visual tracking task (under conditions of ego depletion) and increases in self-reported self-regulatory behaviors over time. In two other studies, Oaten and Cheng (2006b, 2007) explored the impact of real-world self-regulatory exercise by testing students at two points during an academic semester (no exam baseline vs. exam period). Half of the students were randomly assigned to engage in a regular study plan (Oaten and Cheng 2006a) or financial monitoring (Oaten and Cheng 2007) over time. In both studies, performance on the visual tracking experiment improved, and students reported improved self-control across a variety of domains, including reductions in self-reported impulsive buying. Overall, the preceding research provides empirical evidence that consumers can in fact be trained to build up self-control resources over time through repeated selfcontrol exercises. In other words, consumers should show lower impulsive urges following an extended period of self-control exercises (relative to control condition consumers who do not build up their self-control resources through repeated exercises). Although the depletion model of self-control has been tested in numerous settings, relatively little research has focused on testing the benefits of self-control exercises on impulse buying, and much of the previous research on exercise effects has focused on the impact of relatively challenging exercises. Thus, our primary goal for this work is to explore the impact of simple physical and cognitive exercises, practiced over a brief 2-week time span on impulsive buying urges and intentions.
2 Experiment 2.1 Method Undergraduate students (n=178) from a large US university participated in exchange for partial course credit. In the first phase of the study, participants completed two individual difference measures, including the 9-item trait Buying Impulsiveness Scale (BIS; Rook and Fisher 1995) and a 13-item brief trait Self-Control Scale (SCS; Tangney et al. 2004). Two example items on the BIS read: “I often buy things spontaneously” and “I see it, I buy it describes me” (1=strongly agree to 9=strongly disagree). Two example items on the SCS read: “I am good at resisting temptation” and “I have a hard time breaking bad habits” (recoded; 1=not at all to 9=very much). Both scales demonstrated acceptable reliability (BIS α=0.90; SCS α=0.83). In the second phase of the study, participants were assigned to a control or an exercise treatment condition, following procedures used in past research (Muraven et al. 1999). After a 2-week exercise (or no exercise) period, participants returned to the lab and responded to the impulsive buying scenario. To enhance the generalizability of our findings, we conducted two successive (replication) studies involving two different types of exercise (cognitive and physical, as subsequently detailed). In both studies, participants in the exercise conditions performed assigned exercises for 2 weeks following the measurement of the individual difference (i.e., trait BIS and trait SCS). By comparison, in both studies, participants in the no exercise control conditions were not asked to perform
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any activities during the 2-week period between the initial and subsequent phases of the study. In the final phase, all participants were presented with a scenario depicting an impulsive buying situation (Dholakia et al. 2006) and completed the focal dependent measures (i.e., impulsive buying urges and intentions scenario; details to follow). In the first study (n=33), participants in the exercise condition were instructed to engage in a cognitive exercise (i.e., the Stroop color naming task; Stroop 1935). Specifically, participants were instructed to name the color of words presented on a screen (e.g., if the word blue appears in red, the respondent should say “red”). Because the perceiver’s tendency is to name the word itself (rather than the color of the text), the Stroop exercise requires cognitive control and an ability to focus one’s attention. While previous research has used the Stroop task as an ego depletion task (Bruyneel et al. 2009), we reasoned that requiring participants to engage in the Stroop task over a period of 2 weeks would build self-control resources, as participants gradually learned to improve their performance on the task. In the current study, the Stroop task was administered via a web site on which participants were asked to type the color of ink in which each word (the name of a different color) was printed. The color of the text was changed after each visit to reduce participants’ familiarity with the exercise. To increase compliance, participants were periodically sent an email reminding them to perform the Stroop exercise. In the second study (n=145), participants in the exercise condition were instructed to engage in a physical exercise (i.e., sitting up straight and walking erectly). Specifically, participants were instructed to visit a website every few days for a period of 2 weeks where they typed words appearing in an article provided to them and were asked to maintain good posture (and to avoid bad posture) while completing the task. Good and bad postures were illustrated on the website via pictures of individuals sitting appropriately (vs. inappropriately). Individuals in the pictures were two PhD students unknown to the research participants. Further, participants in the physical intervention were asked to walk erectly during the 2-week period on a daily basis. To ensure that they followed the correct method, participants were provided with a procedure and pictures that would help them sustain a good posture as they walked. As in the cognitive exercise study, participants were periodically sent an email reminding them to log onto the website and perform the relevant physical exercises. After the 2-week exercise (or no exercise) period, all participants were brought to the lab to respond to the impulse buying scenario developed by Dholakia et al. (2006). Specifically, participants were asked to put themselves in the place of Ms. (Mr.) A in the following impulse buying scenario and then indicate their urge and intentions to buy the described shirt: Ms. (Mr.) A is a 22-year old college student with a part-time job. It is two days before she (he) gets the next paycheck and at present, she (he) has only $40 left for necessities in her (his) bank account. In addition, she (he) does have two credit cards that she (he) sometimes uses. Today, Ms. (Mr.) A needs to buy a pair of shoes for an upcoming party this weekend. After work, she (he) goes with her (his) friend Ms. (Mr.) B to the mall to purchase the shoes. As they are walking in the mall, Ms. (Mr.) A sees a great looking shirt on sale. The helpful
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salesperson tells Ms. (Mr.) A that they have just one piece left in her (his) size, and it is unlikely that they will get more pieces in this style in the future. To verify the realism of the scenario, we asked a separate group of upper division marketing majors (n=28) to read the scenario and (a) rate whether they believed the scenario was realistic (1 = strongly disagree to 7 = strongly agree); (b) rate whether they believed the scenario was believable (1 = strongly disagree to 7 = strongly agree), and (c) indicate how likely they would be to encounter a situation similar to the one described in the scenario (1 = very unlikely to 7 very likely). Reliability analysis indicated that the three items could be combined to form a scale (alpha= 0.74). Importantly, the mean on this three-item realism scale (M=5.77, SD=0.99) was comfortably above the scale midpoint of 4, t(27)=9.52, p0.15). In sum, results reveal that the effect of experimental treatment was not influenced by the intervention type. Accordingly, for our primary analysis, we collapsed across intervention type and focused solely on the effect of experimental treatment on purchase desirability and intentions using independent sample t tests. Means were in the expected direction: relative to those in the no exercise control group, participants in the exercise treatment expressed a significantly lower desire to purchase the shirt (MExercise =5.16, MNo Exercise =5.96, t(176)=2.03, p
