2 CONSUMER RESPONSE TO UNCERTAIN PROMOTIONS: AN EMPIRICAL ANALYSIS OF CONDITIONAL REBATES Kusum L. Ailawadi a,*, Karen Gedenk b, Tobias Langer c, Yu Ma d, and Scott A. Neslin e Tuck School of Business, Dartmouth College, 100 Tuck Hall, Hanover, NH 03755, U.S., [email protected] b University of Hamburg, Welckerstr. 8, 20354 Hamburg, Germany, [email protected] c 1618 N Campbell Ave #3, Chicago, IL 60647, U.S., [email protected] d University of Alberta, Edmonton, AB, T6G 2R6, Canada, [email protected] e Tuck School of Business, Dartmouth College, 100 Tuck Hall, Hanover, NH 03755, U.S., [email protected] * Corresponding author. Tel.: +1 603 646 2845; fax: +1 603 646 1308. Vo l um e 31 #1 20 14 a g IJ R M Note: Authors are listed in alphabetical order to reflect their equal contribution to the paper. m in Article history: Fo ARTICLE INFO rth co ========================================================== First received in August 31, 2012 and was under review for 3 ½ months. Area Editor: Olivier Toubia ============================================================ 3 Acknowledgements: The authors thank Neeraj Arora of the University of Wisconsin, Imran Currim of the University of California, Irvine, Rakesh Sarin of UCLA, and session participants at the 2011 Marketing Science Conference, 2012 ISMS Practice Conference, Universidad Carlos III de Madrid, KU 14 Leuven, and Tuck School at Dartmouth for helpful comments. They are also grateful to the AE Fo rth co m in g IJ R M Vo l um e 31 #1 20 and reviewers for their valuable suggestions. 4 CONSUMER RESPONSE TO UNCERTAIN PROMOTIONS: AN EMPIRICAL ANALYSIS OF CONDITIONAL REBATES Abstract: We formulate, estimate, and analyze a model of consumer response to promotions where 20 14 consumers’ receipt of the promotional reward is uncertain. The model incorporates consumers’ #1 risk aversion and their subjective assessment of the probability that they will get the reward. It is 31 used to assess the effectiveness of a “conditional rebate”, where the uncertainty arises because um e the reward is contingent on an external event, versus a traditional rebate, which is similar in all Vo l respects except that it is certain. We estimate the model using a conjoint choice experiment. M Response to conditional rebates is highly segmented and related to perceived thinking costs and IJ R savings and entertainment benefits of conditional rebates as well as to event involvement and m in g gambling proneness. In our application, conditional rebates are more cost effective than certain rth co rebates, mostly because consumers’ subjective probability of the event occurring is higher than Fo what market wisdom suggests. Keywords: uncertain rewards, promotions, conditional rebates, consumer utility model, risk aversion, subjective probability 5 1. Introduction Marketers are always looking for promotions that generate excitement and interest, stimulate sales, and increase profits. Promotions offer a reward, for example a discount, gift, or extra product, to the consumer who buys the company’s product. For the majority of promotions, receipt of the reward is a certainty, but there are also several promotions where it is 14 not. Uncertainty may be due to (a) the consumer’s own skill, e.g., contests; (b) pure luck, e.g., 20 sweepstakes; (c) the marketer’s decision to express the reward level as “tensile”, e.g., “X% to #1 Y% off this week”; or (d) whether an external event occurs, e.g., “Buy the product now and get 31 $X off if the Red Sox win the World Series”. um e Two issues immediately come into play with uncertain promotions: (1) consumers’ risk Vo l aversion, and (2) consumers’ perceptions of the probability, i.e., their “subjective probability”, of R M receiving the reward. Consumers are typically risk averse, which should work against uncertain g IJ promotions. However, consumers may believe the likelihood of receiving a reward is higher m in than it really is, due to innate optimism or an upward bias in assessing the probability of positive rth co events. This should work in favor of uncertain promotions. Fo Laboratory research provides important insights on how consumers respond to some types of uncertain promotions (e.g., Dhar, Gonzalez-Vallejo, & Soman, 1995; 1999; Goldsmith & Amir, 2010; Mazar, Shampanier, & Ariely, 2012). However, these studies simply document average purchase likelihood or the percentage of consumers who prefer one or the other type of promotion. To the best of our knowledge no one has developed and estimated a model of consumer response to uncertain versus certain promotions. The benefit of a model is that, in addition to the insights one can obtain from lab studies, it provides a decision tool to predict consumer response to choices not necessarily presented in the measurement. 6 We develop such a model in this paper and show how it can be used by marketers to determine whether, and for whom an uncertain promotion may be more effective than its certain counterpart. Our model captures risk aversion and the consumer’s subjective probability of getting a reward, and allows for heterogeneity in these as well as other model parameters. We apply this model to a class of uncertain promotions that has become increasingly prevalent in recent years. In these promotions, often termed “conditional rebates”, the consumer makes a 14 purchase at time t and receives a reward at a subsequent time t+x conditional on an uncertain #1 money back if their home team wins a sports championship. 20 external event occurring between t and t+x. For example, many companies offer their customers e 31 Table 1 lists examples of conditional rebates that we have compiled from the internet. As um the table shows, these promotions are used in many countries; they are offered on big-ticket and Vo l relatively high-involvement products; and the external event usually involves sports or the R M weather. An entire industry has been built around such promotions, consisting of companies like g IJ Oddsonpromotions.com, Interactive Promotions Group, Sadler Sports and Recreation Insurance, m in SCA Promotions, and GrandPrizePromotions.com. These companies help client firms Fo these promotions. rth co implement conditional rebates, contests, and sweepstakes and offer insurance indemnification for < Insert Table 1 about here > As noted above, conditional rebates are characterized by uncertainty and delayed rewards. Figure 1 categorizes different types of promotions in terms of these attributes. Given our goal of modeling the effectiveness of uncertain versus certain promotions, and our specific interest in examining conditional rebates, we compare conditional rebates to their closest certain analog, i.e., traditional rebates (hereafter termed “certain rebates”). As discussed for example by 7 Baucells and Heukamp (2012), consumers have both a monetary discount rate (trading off outcomes they receive immediately versus with a delay) and a probability discount rate (trading off outcomes they receive with uncertainty versus certainty). Since we are interested in isolating the impact of uncertainty, it is important to ensure the comparison is between promotions that are similar in terms of delay. Both conditional rebates and rebates are delayed. <Insert Figure 1 about here> 14 To summarize, our objective is to present a model for quantifying consumer response to 20 conditional rebates, as an example of the broader class of uncertain promotions, compared to #1 certain rebates. Our substantive contribution lies in (a) assessing the relative attractiveness of a e 31 unique but prevalent type of uncertain promotion that has not been studied previously; (b) um quantifying the market share impact of conditional rebates compared to rebates; and (c) Vo l characterizing segments of consumers who differ in their response to such promotions. Our R M methodological contribution lies in developing a consumer utility model that incorporates risk g IJ aversion and subjective probability. We estimate the model using a conjoint experiment, m in establish its superior fit and predictive validity over simpler benchmark models, and use the rth co estimated model to simulate market shares of competing products in different promotion Fo scenarios. Our model is useful for understanding consumer response to conditional rebates as well as other types of uncertain promotions, and as a tool that can help managers decide whether and for whom to utilize these promotions rather than their certain counterparts. A few of our key empirical findings are as follows. First, we identify three segments that differ substantially in their response to conditional rebates. Segment membership is driven by perceived benefits and costs of conditional rebates, gambling proneness, and event involvement. Second, market share simulations suggest that in our application, a conditional rebate can be 8 more cost effective than a certain rebate in that it can recover the share lost to a competitor’s certain rebate at a lower expected cost and hence greater profit. Third, consumers tend to overestimate the probability of the event in the conditional promotion, enhancing its cost effectiveness. Fourth, conditional rebates are more effective for TVs than for washing machines, perhaps because TVs are hedonic, and washing machines are utilitarian. The rest of the paper is organized as follows. In section 2 we review prior research, 14 before we present our modeling framework in section 3. This is followed by a description of our 20 data in section 4, and our empirical results in section 5. We conclude the paper with a summary #1 of our key findings and implications for managers and researchers in section 6. e 31 2. Prior Research um 2.1 Consumer Response to Uncertainty Vo l Prior research on consumer response to uncertainty suggests a tension with respect to R M which will be more effective – a certain rebate or an uncertain conditional rebate. On one hand, g IJ consumers may prefer a certain promotion because of risk aversion. Consumers have been found m in to be risk-averse, even extremely so, in a variety of situations (Iyengar , Jedidi, & Kohli, 2008; rth co Narayanan & Manchanda, 2009; Roberts & Urban, 1988; Gneezy, List, & Wu, 2006). Fo On the other hand, a conditional rebate may be more effective because consumers overestimate the probability that the event will occur. They may believe they are luckier than others (Wagenaar & Keren, 1988) or have innate optimism (Alloy & Abramson, 1988; Goldsmith & Amir, 2010). There is a strong “affinity” aspect to these rebates when they are linked to sporting events, e.g., the Boston Red Sox winning the World Series or the German team winning the European Soccer Championship, and people overestimate the probabilities of vivid (Johnson et al., 1993; Lichtenstein et al., 1978; Weber & Hilton, 1990), desirable (Babad, 1987; 9 Fischer & Budescu, 1995) and salient events (Bar-Hillel, Budescu, & Amar, 2008). They may therefore think the likelihood of receiving a reward is higher than it really is. This tension underscores the need to empirically assess the effectiveness of conditional rebates versus rebates and to incorporate both risk aversion and subjective probability in modeling consumer response. 2.2 Effectiveness of Uncertain Promotions Laboratory experiments have found positive consumer response to uncertain promotions 14 in some situations. Mobley, Bearden, and Teel (1988) and Dhar, Gonzalez-Vallejo, and Soman 20 (1995; 1999) show that consumers prefer tensile claims, where the size of the discount is #1 uncertain, over certain discounts when the probability of getting a discount is low. Goldsmith e 31 and Amir (2010) show that in a low-stakes situation that does not demand much thinking (e.g., um choices involving candy as a reward) consumers prefer uncertain rewards almost as much as the Vo l more preferred outcome, and suggest that this is driven by innate optimism. Mazar, Shampanier, R M and Ariely (2012) show that given a choice between a certain promotion (e.g., 1/3 off the price of g IJ a candy bar) versus an uncertain promotion of equal expected value (e.g., 1/3 chance of getting m in the candy bar free) consumers are generally more likely to choose the latter because they want to rth co avoid the “pain of paying”. Fo However, conditional rebates differ from the types of uncertain promotions studied previously in important ways that leave open the question of their effectiveness. First, they require the consumer to make a purchase decision with the possibility of getting a reward later if the event occurs. Thus, they do not alleviate the “pain of paying”. Second, conditional rebates are usually offered on big-ticket products, as are rebates. Thoughtful consideration, which Goldsmith and Amir (2010) find inhibit the attractiveness of uncertain promotions, is much more likely in such contexts. Third, the uncertainty in conditional rebates depends not on stated odds 10 as in the studies discussed above, but on the consumer’s subjective probability that the external event will occur. This needs to be modeled given evidence from prior research that there are biases in probability assessment, especially for vivid and desirable events. Finally, previous studies only report average purchase likelihood or percentage of consumers who prefer one or the other type of promotion. Without an underlying model of consumer utility, one cannot simulate choices and market shares under different scenarios to 14 assess the effectiveness of different types of promotions from the firm’s perspective. 20 2.3 Heterogeneity in Response to Uncertain Rewards #1 To the best of our knowledge, there is little research on heterogeneity in response to e 31 uncertain promotions. However, the literature suggests promotions provide not only economic um benefits like savings, but also hedonic benefits like entertainment (Chandon, Wansink, & Vo l Laurent, 2000; Raghubir, Inman, & Grande, 2004), and consumers may differ in how they R M perceive these benefits. Gambling has entertainment value and shares some elements with g IJ uncertain promotions, so gambling proneness may be associated with response to conditional m in rebates. Excitement and sensation-seeking are important motivations for gambling (Coventry rth co &Brown, 1993; Pantalon et al., 2008). Presumably, consumers who are more involved with the Fo external event will get more excitement from participating in a conditional rebate. Conditional rebates may require more thinking, a cost which some consumers can handle better than others. Finally, demographic variables may contribute to heterogeneity since they are associated with gambling and promotional games (Chalmers & Willoughby, 2006; Fang & Mowen, 2009; Mok & Hraba, 1991). 11 In summary, response to conditional rebates may be associated with consumer characteristics such as the perception of savings and entertainment benefits, thinking costs, gambling proneness, and involvement with the event, as well as demographics variables. 3. Modeling Framework 3.1 Overall Approach 14 We formulate a utility model that incorporates the consumer’s risk aversion and 20 subjective probability of the event occurring, while allowing for heterogeneity in these as well as #1 the other elements of the model. We first use a simulated data test to ensure we can identify the e 31 model. We then estimate the model using choice data from a conjoint experiment. Respondents um choose between two products offered in a series of choice sets. A product may be offered Vo l without a promotion, with a certain rebate, or with a conditional rebate, and the promotions have R M different discount levels. Finally, we use our parameter estimates to simulate choices under in m 3.2 Consumer Utility Model g IJ different scenarios and compare the effectiveness of conditional rebates to that of rebates. rth co We assume the consumer makes choices to maximize expected utility, which depends on Fo (1) the consumer’s preference for the brand associated with the product, (2) the quality of the product, (3) the discount offered with a conditional rebate or a certain rebate, (4) the consumer’s subjective probability that the event will occur in the case of a conditional rebate, and (5) other factors not observed by the researcher. We employ a quadratic utility function (e.g., Iyengar, Jedidi, & Kohli, 2008; Narayanan, Manchanda, & Chintagunta, 2005), which can capture both risk averse and risk prone behavior. 12 A disadvantage of the quadratic utility function is that it is potentially non-monotonic in the amount of the discount. However, within the range of discounts investigated in our study, this occurred in only one out of twelve cases (two types of promotion × three segments × two categories). We also tested a piece-wise linear model, exponential and logarithmic functions. None of these alternatives dominated the quadratic function in hold-out fit and prediction. The hold-out log-likelihood with the exponential function was slightly better in one product category 14 but clearly worse in the other, and the exponential model estimates were highly sensitive to 20 starting values. Therefore, we use the quadratic function in all our analyses. #1 Expected utility is given by: Vo l um e 31 (1) , Consumer c’s expected utility for product i in choice set j. Qualijc = Quality of product i in choice set j of consumer c. Discijc = Discount offered for product i in choice set j of consumer c. Rebijc = m in g IJ R E(Uijc) = rth co M where: Fo 1 if certain rebate offered for product i in choice set j of consumer c, 0 otherwise. CRijc = 1 if conditional rebate offered for product i in choice set j of consumer c, 0 otherwise. pc = Consumer c’s subjective probability that the condition specified in the conditional rebate will occur. βic0 is consumer c’s baseline preference for the brand associated with product i (there are two brands in the study); and εijc reflects factors influencing customer c’s expected utility for product i in choice set j, not observed by the researcher. If a certain rebate is offered, the 13 expected contribution to utility from the discount is , whereas if a conditional rebate is offered, the expected contribution is . Note that we allow different discount parameters for the certain rebate versus the conditional rebate (βc2 and βc3 vs. βc4 and βc5). This is important given the distinction made in decision science research between strength of preference, i.e., the marginal value of additional outcomes, and intrinsic risk attitude (e.g., Dyer & Sarin, 1982; Smidts, 1997). For both certain 14 rebates and conditional rebates, we compute the traditional Arrow-Pratt index of relative risk 31 , and e (2) #1 20 aversion, Rc (Pratt, 1964) which equals the negative of the elasticity of marginal utility:1 Vo l um . (3) M For the certain rebates, Rc captures strength of preference, i.e., a positive RcREB would IJ R simply mean that marginal utility becomes smaller with increasing discounts. Because in g conditional rebates contain uncertainty, RcCR captures the consumer’s inherent risk attitude in rth co m addition to strength of preference. Fo As we discussed previously, consumers typically have biases in their subjective probability assessment. This makes it important to use their self-assessed probabilities of the event even if a more objective measure (e.g., based on the wisdom of the market) is available. However, cumulative prospect theory suggests that using consumers’ stated probabilities as is may not be wise, because when making decisions under uncertainty consumers overweight small probabilities and underweight moderate and high probabilities (Tversky & Kahneman, 1992). 1 A negative Arrow-Pratt index implies risk proneness and a positive value implies risk averseness. 14 We therefore use each consumer’s self reported probability of the event (sp) but apply the probability weighting function proposed by Prelec (1998):2 (4) , where 0 < α < 1. As α approaches 1, there is no weighting, i.e., pc equals the stated probability. As α approaches 0, pc is constant at 0.37, and for α values in between, small stated probabilities are over-weighted, while large probabilities are under-weighted. 14 One could also estimate pc from consumers’ choices. However, this would require 20 constraining the discount parameters to be the same for certain rebates and conditional rebates 31 #1 (βc2=βc4 and βc3=βc5) in order to identify the model. Conceptually, we believe it is better to use e the information contained in self-reported probabilities and retain the important property of Vo l um different discount parameters for rebates vs. conditional rebates. Still we did test a model with M estimated pc and found that it did not improve fit and prediction compared to our proposed model IJ R described in Equations 1 and 4.3 rth co , Fo (5) m in g We can write Equation 1 as: where Vijc is consumer c’s deterministic utility for product i in choice set j. Assuming the unobserved factors εijc are independently distributed extreme value Type 1 (Gumbel), and the consumer is choosing between two products i and k, we have a binomial logit model: (6) , 2 3 We thank the review team for suggesting this weighting function. We tried a more flexible two-parameter weighting function also proposed by Prelec (1998), but it was not identified. Details are available from the authors upon request. 15 where Probijc is the probability that consumer c chooses product i rather than k in choice set j. 3.3 Heterogeneity We model heterogeneity using a latent class model with concomitant variables (Kamakura, Wedel, & Agrawal, 1994; Wedel & Kamakura, 2000). This model is very flexible in that we do not need to make assumptions about the distribution of parameters, and it allows us to derive meaningful interpretations for managers who are used to thinking about segments of , e 31 (8) Vo l um (9) Probability that consumer c chooses brand i in choice set j, conditional on belonging to segment s. Vijcs = Deterministic utility of consumer c for product i in choice set j, conditional on belonging to segment s. L = Likelihood function. ηcs = M Probijcs = rth co A priori probability that consumer c belongs to segment s. Fo Yjc m in g IJ R where: 20 , #1 (7) 14 consumers with different preferences. Our model thus becomes: = 1 if consumer c chooses brand i in choice j; 0 if consumer c chooses brand k. We ensure that the a priori probabilities of segment membership ηcs lie between 0 and 1 and sum up to 1 across segments for each consumer through the following formulation: (10) . The probabilities of segment membership are in turn a function of concomitant variables. Based on the literature reviewed previously, we include perceptions of savings and entertainment 16 benefits, thinking costs, gambling proneness, and involvement with the event as concomitant variables: (11) mcs = γs0 + γs1Savec + γs2Entc + γs3Thinkc + γs4Invevc + γs5Gambc , where: = Savings benefit of conditional rebates perceived by consumer c. Entc = Entertainment benefit of conditional rebates perceived by consumer c. Thinkc = Thinking costs of conditional rebates perceived by consumer c. Invevc = Involvement of consumer c with the event in the conditional rebate. Gambc = Gambling proneness of consumer c. #1 20 14 Savec 31 We initially also included gender, education, income, and age, but their effects were not um e statistically significant and likelihood ratio tests showed that, jointly, they did not improve fit. Vo l Therefore, we have dropped these demographic variables from subsequent analyses. We obtain R M maximum likelihood estimates of all the model parameters jointly.4 g IJ 3.4 Model Identification m in The procedure we use to check model identification is as follows. We create simulated rth co data sets for 200 consumers based on our conjoint design with known values for the parameters Fo and three segments. We then see whether our estimation can recover those parameters. We do not include concomitant variables because our interest here is simply in ensuring identification of our core utility model. In the Appendix, we present results for two sets of true parameter values – one very similar to our results in the washing machine category, the other arbitrary. The 4 We test various sets of starting values for the model parameters. We also rescale the Discount variable to avoid very small discount parameters and facilitate estimation. We thank Kenneth Train for suggesting this rescaling. 17 parameter estimates are not sensitive to starting values and none is significantly different from its true value. Thus, we are confident that our model is identified. 4. Data We utilize data from a choice-based conjoint experiment. Compared to methods for measuring utility functions common in decision analysis, where respondents have to indicate a certainty or probability equivalent (Smith & von Winterfeldt, 2004; Wakker & Deneffe, 1996), 14 making choices between pairs of products is easier and more realistic (see Iyengar, Jedidi, & 20 Kohli, 2008 for another example of using conjoint analysis to estimate utility functions). While #1 we would have liked to make our conjoint analysis incentive-compatible (Ding, Grewal, & e 31 Liechty, 2005; Dong, Ding, & Huber, 2010), this is not feasible for the high-ticket products that um rebates are typically used with – we could not make consumers pay that much and live with their Vo l decisions. Note however, that any bias due to the lack of incentive-compatibility applies to both R M certain and conditional rebates and should not affect the comparison between them. g IJ We investigate two product categories, TV sets and washing machines. Both are high- m in ticket durables but TVs are more hedonic and washing machines are more utilitarian. We rth co conducted the study with German consumers solicited from an online panel provider in the Fo summer of 2011. The external event for conditional rebates is often a major sports event (see Table 1). We therefore chose the 2012 European Football Championship as our event, and the condition for getting the conditional rebate was that the German team wins the championship. The questionnaire consisted of three sections. The first screened respondents to select those who either owned a washing machine/TV or were planning to buy one in the next two years, and who are involved in the purchase decision. The second section was the choice-based conjoint task. The third section obtained additional information from respondents including 18 perceived benefits and costs of conditional rebates, involvement with the event, and gambling proneness. Demographic information was available from the panel provider. 4.1 Design of Conjoint Experiment For each product category, we designed a full-profile choice-based conjoint study. The washing machines were specified to be front-loading and offered at a regular price of 600 €. The TV sets were 32” flat screen HDTVs, also offered at a regular price of 600 €. The stimuli 14 differed in brand, quality, and promotion (Table 2). In each category, we chose two well-known 20 national brands that sell at similar prices. We used quality ratings by Stiftung Warentest, a #1 consumer product rating agency (similar to Consumer Reports in the U.S.), that is well-known e 31 and highly respected in Germany. The ratings are on the same scale as German school grades um (from 1 for “excellent” to 5 for “not sufficient”) and therefore very familiar to consumers. We Vo l used two levels, 2.3 representing “good” and 2.7 representing “satisfactory”. R M < Insert Table 2 about here > g IJ A brand may be offered without a promotion, with a certain rebate, or with a conditional m in rebate. We chose three discount levels for the certain rebate – 30, 60, and 90 €, which rth co correspond to price reductions of 5, 10, and 15% respectively. Both the absolute amount and Fo percentage discount are realistic given values observed in practice (Silk, 2004; Spencer, 2002). At the time of our survey, a well-known betting website (www.bwin.com) offered odds that translated to a 20% probability of the Germans winning the 2012 tournament. This “market wisdom”, based on the assessment of the betting market, is a reasonable proxy for the objective probability of the event a company might use in its planning. Accordingly, we used a 20% 19 probability to compute conditional rebate discounts that are actuarially equivalent to the certain rebate discount levels. These conditional rebate discount levels are 150, 300, and 450 €.5 In the survey, respondents first saw a scenario description. For TV, it read (for washing machines, only the category name and product details were replaced): 14 “Imagine that today is two weeks before the beginning of the 2012 European Football Championship (UEFA EURO 2012), which will take place from June 8 to July 1, 2012 in Poland and Ukraine. Assume that Germany has qualified as section winner and will play Croatia, Sweden, and France in the first round. Beside the hosts – Poland and Ukraine – Spain, the Netherlands, Italy, Portugal, England, Russia, Czech Republic, Slovakia, Denmark, and Slovenia have qualified for the tournament. 31 #1 20 Imagine you have decided to buy a new TV. You have already gathered information about current TV models and decided that you will buy a 32‘‘ flat screen HDTV from an electronics retailer close to your home. Vo l um e In the following we will show you several pairs of TVs. The TVs differ in brand name, picture quality, and the type of promotion offered if any. Assume that the regular price of both TVs is 600 € and they are also identical in all other respects.” IJ R promotions were described as follows: M This was followed by a description of the brand, quality, and promotion attributes, in which the rth co m in g “Rebate promotion: Buy this flat screen HDTV before the beginning of the UEFA EURO 2012. Just mail in your receipt and the company will refund X € to you within six weeks of receiving your receipt. Fo Conditional promotion: Buy this flat screen HDTV before the beginning of the UEFA EURO 2012. Just mail in your receipt and if Germany wins the Championship, the company will refund X € to you within six weeks of receiving your receipt.” Thus, the description of the promotions is identical except for the condition in the latter. Next, respondents faced several choice tasks in each of which they chose one product out of two.6 Figure 2 shows a sample choice task. We created stimuli and conjoint choice sets using 5 Our design may inflate the importance of promotions because the number of levels for this attribute is higher than for the others (Wittink, Krishnamurthi, & Reibstein, 1990), and because our design uses only three attributes. However, if such a bias exists, it applies to certain rebates and conditional rebates to a similar degree, and we are more interested in their relative than absolute impacts. We therefore did not increase the number of levels for other attributes, which would have increased respondent burden. 20 the “complete enumeration” procedure in Sawtooth. This produces a randomized conjoint design wherein each consumer receives different stimuli and this design accounts for the principles of (1) minimal overlap, i.e., each attribute level is shown as few times as possible within a single choice task; (2) level balance, i.e., the levels of an attribute occur with equal frequency; and (3) orthogonality, i.e., all attribute levels are chosen independently of other attribute levels (Hennig-Thurau et al., 2007; Huber & Zwerina, 1996). Each respondent 14 completed twelve choice tasks that were used for model estimation. We randomized the order of 20 brand presentation to avoid order effects, but always presented product attributes in the same #1 order to avoid respondent confusion. e 31 < Insert Figure 2 about here > um 4.2 Consumer Characteristics Vo l Respondents indicated their subjective probability of the event occurring by answering R M the following question: “What do you think is the percentage chance that Germany will win the g IJ 2012 European Football Championship? (Please write in a number between 0 and 100)”. m in Respondents also indicated whether they had bought something with a certain or conditional rth co rebate during the last three years. Finally, we measured perceptions of the benefits and costs of Fo conditional rebates as well as the other consumer characteristics that serve as concomitant variables in our model. Most items were taken from previously validated scales, as indicated in 6 We did not include a no-choice option to discourage respondents from choosing the “easy way out”. Our choice tasks are complex, and previous research has shown that task complexity increases the likelihood of choosing the no-choice option (Dhar, 1997; Tversky & Shafir, 1992). Not having a no-choice option does not pose a problem for our analysis since we predict market shares not absolute sales levels. Also, choice sets with pairs are less efficient and realistic than choice sets with more alternatives (Sándor & Wedel, 2002) but they are easier for respondents to process. This increases internal validity (Louviere et al., 2008) and allows us to use more choice sets (Zeithammer & Lenk, 2009). 21 Table 3. Participants were asked to indicate their agreement with these statements on a scale from 1 (strongly disagree) to 5 (strongly agree). < Insert Table 3 about here > 4.3 Data Collection The data were collected through an online survey in June 2011. Both certain and conditional rebates are rather new to the German market, so we do not expect a bias from 14 respondents being more familiar with one type of promotion than the other. One year before the 20 event used in our conditional rebate is an appropriate time for data collection. The event was #1 sufficiently salient, since the national teams were in the process of qualifying for the tournament, e 31 and ticket sales had started. Also, the odds of the German team winning were stable and not um affected by short-term news, e.g., about players’ injuries. Vo l We specified to the panel provider a sampling frame of adults between the ages of 18 and R M 79 with at least a secondary school degree (“Realschule” or higher) in order to assure response g IJ quality, and asked that our sample reflect the gender and age distribution of the German m in population. This sampling frame accounts for 92% of the online provider’s panel and about 60% rth co of the German adult population over 20 years of age (www.destatis.de). Respondents were Fo randomly assigned to the washing machine or the TV category. The samples contained 376 respondents for washing machines and 375 for TVs. Respondents who took less than 4 minutes, more than 24 hours, or gave straight line responses to all the choices were deleted as part of survey quality control. The eliminated respondents were not significantly different from those retained except for a slightly lower education level in the washing machine sample. Our final sample size is 293 for washing machines and 271 for TV. 4.4 Descriptive Statistics 22 We summarize key characteristics of the two samples in Table 4. The data confirm that German consumers have low experience with both certain and conditional rebates. Interestingly, their self-reported probability is highly optimistic. The average (58% / 57%) is much higher than what is suggested by market wisdom (20%). This is consistent with prior research showing consumers’ propensity to overestimate the probability of desirable and salient events or engage in wishful thinking. Such overestimation may be surprising given that we ran our study one year 14 before the event actually took place and construal-level theory suggests that temporal distance 20 activates abstract construal which in turn leads to under-estimation of probability (Trope & #1 Liberman, 2003; Wakslak & Trope, 2009). However, psychological distance is just as important e 31 as temporal distance and the event’s salience is likely to reduce its psychological distance. um < Insert Table 4 about here > Vo l 5. Results R M We first determine the number of segments for our model using the Bayesian Information g IJ Criterion (Schwarz, 1978). We find that the BIC is best for the three-segment solution in both m in categories, so we use three segments for all further analyses. In the following, we compare our rth co model with simpler benchmark models. We then discuss our parameter estimates and conduct Fo market share simulations. 5.1 Comparison with Benchmark Models We compare our proposed model to three benchmark models nested within it. Since the key characteristics of the utility function for conditional rebates are subjective probability and risk aversion, we choose benchmark models with simpler treatments of pc and of the discount parameters. We start with a model without promotions, i.e., with only brand and quality as independent variables (model B1). We then add promotion effects in their simplest form, i.e., we 23 use respondents’ stated subjective probabilities directly and constrain the discount parameters to be equal for certain and conditional rebates (model B2). Next we relax the equality constraint on the discount parameters (model B3). Finally, we bring in the probability weighting, which leads to our proposed model. We estimate all models using 200 randomly selected respondents leaving the rest (93 for washing machines and 71 for TVs) for hold-out analysis. Table 5 presents in-sample fit and 14 hold-out performance for all the models. We obtained hit rates as follows. For each hold-out 20 respondent, we first computed choice probabilities and consequent hit rates in each of the three #1 segments. Next, we computed the overall hit rate for the respondent as the weighted mean across e 31 segments, using the a posteriori probabilities of segment membership as weights. Finally, we um aggregated this hit rate across all the hold-out respondents. Vo l < Insert Table 5 about here > R M Our benchmark comparisons confirm that promotions are important – in-sample and g IJ hold-out log-likelihoods improve significantly when we add promotion to the model (B2 vs. B1). m in The improvement in hit rates is not large – brand and quality are relatively important for rth co respondents and already explain a large portion of consumers’ behavior, yielding hold-out hit Fo rates of 72.8% (washing machines) and 78.6% (TV). This could be due to the choice tasks being hypothetical and not incentive-compatible – in practice promotion effects may be larger because consumers spend and save real money. While this means we may be underestimating the absolute effectiveness of promotions, it should not influence the comparison between certain and conditional rebates, which is of key interest. Next, we make the discount parameters promotion-specific. This significantly improves in-sample fit (B3 vs. B2). Also hold-out performance becomes better, and the extent of that 24 improvement is meaningful, given that hit rates are already high in a model with no promotion effects (B1). Finally, we move to our proposed model by adding the weighting of stated probabilities as specified in Equation 4. Hold-out performance stays rather similar with a slight improvement for TV, but not for washing machines (PM vs. B3). However, in-sample fit improves in both categories, so we report results based on our proposed model. 5.2 Model Estimates 14 Table 6 provides estimates for the washing machines sample. We find one large segment 20 with 58% of respondents, and two smaller segments with 18% and 24%. The estimates of β0 #1 reflect brand preferences, which vary across the three segments. The estimates of β1 are e 31 plausible: utility increases with higher quality (β1 > 0), and there is substantial heterogeneity um across segments. Quality sensitivity is rather high in the largest segment. This is consistent with Vo l our earlier finding of high hold-out hit rates even without promotion in the model. R M < Insert Table 6 about here > g IJ For each segment, Table 6 also lists the mean subjective probabilities stated by m in respondents (sp) as well as the transformed p’s based on the probability weighting coefficient α. rth co In all three segments the transformed p’s are smaller than the probabilities stated by respondents Fo (.49, .47, and .37 vs. .56, .65, and .57). Thus, the transformed p’s are more realistic than the stated probabilities, but still substantially larger than the .20 suggested by market wisdom. This is in line with previous research showing that consumers tend to overestimate probabilities of favorable and salient events, and bodes well for the effectiveness of conditional rebates. In segment three, the estimated weighting parameter α approaches zero, making the transformed probability .37, and this segment is not sensitive to the conditional rebate discount. We note that α would not be identified if the discount parameters were zero. Here, the parameters are non- 25 zero, albeit statistically insignificant, and we did not find any indication of a problem either in model convergence or in robustness to starting values. Table 6 also shows the segment-level Arrow-Pratt indices for certain and conditional rebates, computed by substituting the estimated discount parameters and medium discount levels (60 € for rebates and 300 € for conditional rebates) into equations (2) and (3) respectively. We find that respondents are mostly risk averse (R > 0). In segments 1 and 2 the index is similar for 14 certain and conditional rebates. In contrast, segment 3 is very risk averse for certain rebates, but 20 not for conditional rebates. Recall, though, that the conditional rebate discount parameters are #1 insignificant for this segment, implying that consumers do not respond to them. e 31 Table 7 contains parameter estimates for the TV sample. As for washing machines, we um find one large segment and two smaller ones of about equal size. Again, brand preference and Vo l quality sensitivity are heterogeneous across segments, with quality sensitivity being high in the R M largest segment (segment 1). Segment 1 is also not sensitive to either the certain or the g IJ conditional rebate discount levels. In contrast, segment 2 is sensitive only to conditional rebate m in discounts and segment 3 is sensitive only to certain rebate discounts. Although the discount rth co parameters are often insignificant, we still compute the Arrow-Pratt index which indicates that Fo consumers are mostly risk averse. < Insert Table 7 about here > Segment 3’s stated probabilities do not need to be weighted (α approaches 1). In the other two segments, as for washing machines, transformed p’s are smaller than stated p’s. Again, the overall picture is that subjective probabilities (.42, .36, and .48) are smaller than stated but larger than the .20 suggested by market wisdom. Whether consumers respond better to certain or conditional rebates is determined by the interplay of subjective probability and risk 26 aversion. Next, we analyze how these effects balance out in the different segments and the overall market based on market share simulations. 5.3 Market Share Simulations To gain further insights into the relative effectiveness of certain vs. conditional rebates and the segment structure, and to demonstrate the value of our model as a managerial tool, we conduct market share simulations. We take the perspective of a brand manager working on a 14 promotion program with a specific retailer, having to choose between offering a certain or 20 conditional rebate. We assume the manager knows that a competitor will be offering a certain #1 rebate. Brand A is the focal brand and brand B has instituted a certain rebate at a specified e 31 discount level. If unanswered, this would switch many consumers to brand B. Brand A can um recoup its baseline share by offering the same rebate discount or a conditional rebate. We ask: Vo l What discount level for a conditional rebate would brand A have to implement in order to win R M back its baseline share? We call this the “CR equivalent”. Assume the manager believes the g IJ market-based assessment of the probability of the event (.20 in our case). Let Discr = the certain m in rebate discount. If .20 × CR equivalent < Discr, the expected value of the conditional rebate rth co discount that brand A would have to pay is lower than the certain rebate discount necessary to Fo recoup market share, indicating that conditional rebates are more effective than certain rebates. We first simulate a base case in which consumers choose between brands A and B when they are of equal high quality and neither is on promotion. We use individual parameters to compute choice probabilities for each respondent and aggregate to obtain baseline market shares. Next we repeat the simulation assuming brand B offers a certain rebate of a given discount level, and re-compute market shares. We also confirm that brand A can recoup its baseline share by offering the same certain rebate. Finally, we determine the conditional rebate discount that brand 27 A would have to offer in order to recoup its baseline market share. We repeat these simulations for different levels of the certain rebate discount for brand B and for both categories.7 Figure 3 summarizes the results at the segment level. For washing machines, Bosch served as brand B, which uses a certain rebate, and AEG served as brand A, which uses a conditional rebate. For televisions, brand B was Sony; brand A Philips. Figure 3 shows the CR equivalents for different rebate values. For example, in the washing machine category, if brand #1 < Insert Figure 3 about here > 20 of 117 € to recoup its baseline share with consumers in segment 1. 14 B (Bosch) offers a 30 € certain rebate, brand A (AEG) would have to offer a conditional rebate e 31 The pattern of consumer response is similar in the two product categories. In both um categories, Figure 3 shows that conditional rebates are most effective in segment 2 – CR Vo l equivalents are lowest here, i.e., the smallest discounts are needed for brand A to recoup its R M market share. The large segment 1, which comprises over half the sample in both categories, g IJ responds less strongly to conditional rebates, but even for this segment, conditional rebates are m in more cost effective than certain rebates. For example, in the washing machine category, the CR rth co equivalent of brand A (AEG) for a certain rebate of 90 € by brand B (Bosch) is 295 €. If the Fo manager of AEG assumes the probability of the German team winning the championship is .20 (the wisdom of the market value), then AEG is better off offering a conditional rebate because the expected discount to be paid out, 59 € = .20 × 295 €, is much less than the 90 € certain rebate brand A would need to recoup its share. The same pattern holds at other discount levels. 7 Results are substantively similar in simulations where brand B begins by instituting a conditional rebate instead of a rebate. 28 For consumers in segment 3, however, it is not profitable (or even not possible) for brand A to recover market share with a conditional rebate. The relative values of the discount parameters are such that for washing machines, the CR equivalents are too high (more than the regular price of 600 € to offset a certain rebate of 60 or 90 €). For TV we cannot even compute CR equivalents because a conditional rebate discount of up to 1,200 € is not sufficient to recoup market share and beyond that point, utility starts to decrease with discount. 14 For managers it is important to study CR equivalents at the level of the total market. 20 Figure 4 shows these simulations, and reveals that conditional rebates are more cost effective #1 than certain rebates at all discount levels. For example, in the washing machine category, the CR e 31 equivalent of brand A (AEG) for a rebate of 90 € by brand B (Bosch) is 342 €. Thus, the um expected discount to be paid out for a conditional rebate, 68.40 € = .20 × 342 €, is lower than the Vo l 90 € certain rebate brand A would need to recoup its share. Note that a conditional rebate of 450 R M € has an actuarial equivalent of .20 × 450 € = 90 €. So brand A can offer a conditional rebate g IJ anywhere between 342 € and 450 € and be better off than if it offered a 90 € certain rebate. It m in can recoup its share with a conditional rebate of 342 € or use a conditional rebate between 342 € Fo rth co and 450 € and achieve a higher share at the same expected expense as a certain rebate of 90 €. < Insert Figure 4 about here > Lower CR equivalents for TVs show that conditional rebates are more cost effective in this category than for washing machines. This lends support to the benefit congruency hypothesis proposed by Chandon, Wansink, and Laurent (2000), that hedonic promotions are more effective in hedonic than in utilitarian categories. An alternative explanation could be the higher usage complementarity for TVs than for washing machines – consumers watch soccer on 29 their new TV. This type of fit has been shown to increase the effectiveness of other promotions like premiums (e.g., Harlam et al., 1995). Overall, we find that conditional rebates are more cost effective than certain rebates: they can recoup baseline market share at lower expected cost. Further, they are more effective for TVs than for washing machines. Note that our calculations do not account for possible differences in slippage rates (Gilpatric, 2009; Gourville & Soman, 2011) and insurance or other 14 costs for certain versus conditional rebates. However, our analysis allows firms to assess how e 31 #1 20 large these differences can be for one or the other type of promotion to be more profitable. um 5.4 Observed Heterogeneity Vo l The five consumer characteristics – perceived savings benefits, entertainment benefits, R M thinking costs, gambling proneness, and involvement with the event – help explain heterogeneity g IJ across segments. The bottom halves Tables 6-7 show the impact of these variables on the m in likelihood of being in a particular segment, with segment 3 as the base case.8 To interpret these rth co effects, it is useful to recall that for both categories, segment 2 is the most responsive to Fo conditional rebates, followed by segment 1, and segment 3 is the least responsive. In the washing machine category, we find that higher thinking costs make respondents less likely to be in the conditional rebate prone segments 1 and 2; hence more likely to be in segment 3, which does not like conditional rebates. Higher involvement with the event and higher entertainment value makes respondents less likely to be in the large segment 1, and more 8 We use principal component scores for the consumer characteristics to alleviate multicollinearity. Details of the principal component analysis are available from the authors upon request. 30 likely to either love (segment 2) or hate (segment 3) promotions around the event. In the TV category, higher thinking costs make respondents less likely to be in segment 1. Higher perceived savings and entertainment benefits, along with higher gambling proneness, place respondents in segment 2, the most conditional rebate-prone segment. Overall, we find that consumer response to conditional rebates is driven by perceived thinking costs, but also by perceived savings and entertainment benefits as well as event 14 involvement and gambling proneness. The hedonic aspect of conditional rebates is at least as 20 important as the utilitarian aspect: In the washing machine category, respondents who have high #1 event involvement and associate conditional rebates with high entertainment benefits either love e 31 or hate these promotions, whereas in the TV category, conditional rebate proneness is associated um with high entertainment benefits and gambling proneness. Vo l 6. Discussion and Implications R M We have developed and estimated a model for assessing the effectiveness of uncertain g IJ promotions, focusing on a specific type – conditional rebates. The key features of our model are m in the incorporation of risk aversion and the subjective probability that consumers use in evaluating rth co such promotions. We have used the model to generate insights on how conditional rebates work. Fo We have compared the effectiveness of a conditional rebate linked to a popular sports event versus a traditional certain rebate which is the closest analog amongst traditional promotions without uncertainty. We have done this in the context of choices made by German consumers in two product categories and have generated several interesting results: First, our model successfully recovers the choices consumers make when they trade off a conditional rebate versus a rebate. This is evidenced by hit rates of about 80%, plausible coefficients, and superiority over several benchmark models. We find evidence that risk 31 aversion is different for conditional vs. certain rebates and that subjective probabilities are smaller than stated, but much larger than the probabilities suggested by market wisdom. Second, we find evidence of substantial heterogeneity with respect to response to conditional rebates. Using a latent class approach, we find similar three-segment solutions for both televisions and washing machines. There are high, medium, and low segments with respect to their responsiveness to conditional rebates. We identify consumer characteristics that 14 distinguish between the segments and hence drive the effectiveness of conditional rebates: 20 perceived savings and entertainment benefits, perceived thinking costs, gambling proneness, and #1 event involvement. These results are plausible, and reinforce the segmented response to e 31 conditional rebates. um Third, conditional rebates are more cost effective than certain rebates in that the expected Vo l cost of the discount required to off-set a competitor’s rebate is lower than the cost of that rebate. R M Finally, while the general pattern of results is similar for TVs and washing machines, conditional g IJ rebates are more effective for TVs, the more hedonic product. This is consistent with benefit m in congruency (Chandon, Wansink, & Laurent, 2000), but it could also be due to other reasons such rth co as higher usage complementarity between TVs and sporting events. Fo Our results have important implications for researchers. First, we have developed a consumer utility model that can be used to evaluate consumer response to uncertain promotions and shown that the key phenomena to include are the subjective probability of getting the reward and risk aversion. Second, we add substantively to the literature on uncertain promotions. Some recent research has argued that positive response to uncertain promotions occurs only in low stakes situations with relatively small-ticket items, when consumers do not deliberate (Goldsmith & Amir, 2010) or because consumers want to avoid the pain of paying (Mazar, Shampanier, & 32 Ariely, 2012). None of these situations holds for conditional rebates, which are almost always offered on big-ticket items and the reward is delayed so the consumer does not avoid the pain of paying. Yet we find that conditional rebates can work better than certain rebates. This result is mainly driven by the fact that subjective probabilities are larger than “objective” probabilities based on market wisdom. Third, we add to the literature on deal proneness, which suggests that response to 14 promotion is highly segmented and segmentation varies by type of promotion (e.g., Schneider & 20 Currim, 1991). Indeed, we find that almost a quarter of the consumers in our sample are not at #1 all receptive to conditional rebates, about 50-60% are quite receptive, and the remainder are e 31 highly receptive. Fourth, we contribute to the literature on benefits and costs of promotions. We um show that hedonic benefits can be as important as utilitarian benefits for explaining consumer Vo l response to promotions and the cost of thinking is very relevant, supporting Chandon, Wansink, R M & Laurent’s (2000) call for more work on these costs. g IJ For managers, our key messages are as follows. First, conditional rebates have a role to m in play in the brand’s promotion mix. We find them to be more cost effective than certain rebates rth co in recovering market share when a competing brand uses a certain rebate. Second, promotions Fo are a targeting device (e.g., Nies & Natter, 2010), and conditional rebates are no exception. The segment most attracted by conditional rebates is one that finds promotions less taxing on the brain. Perceived entertainment benefits, gambling proneness, and event involvement can also play a role, but this may differ across product categories. Third, in their communication of conditional rebates, managers should not only emphasize the potential savings, but also how much fun it is to participate. Fourth, models can be used to show how the market for conditional rebates is segmented and to simulate alternative promotion scenarios. The analysis here is not 33 overly complex – it requires a conjoint-type survey followed by a model that can be estimated using maximum likelihood. Our procedure may be especially useful for managers who have never used conditional rebates before and are seeking guidance before a full roll-out. Our work has limitations that suggest avenues for future research. First, the conditional rebates we studied involved a positive event, i.e., a soccer team winning a tournament. In recent years, companies are also offering conditional rebates as “insurance” against negative events. 14 For example, a German manufacturer of solar heating systems offered a discount if the number 20 of hours of sunshine falls below a certain level. And Pirelli promised a refund of up to 50% on #1 the purchase of winter tires, if there are not enough cold days in the next winter. During the e 31 recent financial crisis, some car manufacturers in the U.S. offered to cover monthly payments for um a while if the customer lost his/her job. It would be interesting to see the impact of a negative Vo l external event on the effectiveness of such promotions. R M Second, the event in our analysis was a low but not very low-probability event. It would g IJ be interesting to study the response to much lower probability scenarios. There are at least two m in reasons why those may be even more effective. One is that consumers overweight very low rth co probabilities and exhibit risk proneness when it comes to longshots, i.e., very small chances of Fo large pay-offs, as evidenced by the popularity of state lotteries, especially jackpots (Chew & Tan, 2005). Another is that very low-probability scenarios are often associated with free products (e.g., Jordan’s Furniture Monster Hit promotion) and there is evidence that consumers have much higher affect for free offers than for other price offers (Shampanier, Mazar, & Ariely, 2007). In addition, it may be interesting to study medium probabilities, which may be more attractive for consumers because chances of winning are higher. 34 Third, it would be interesting to compare response to conditional rebates across cultures. In Germany, neither certain nor conditional rebates are widely used. This was good for the purposes of our study, since it equalized baseline responsiveness. However, in the U.S., certain rebates are very common, although widely criticized, so it would be interesting to see whether conditional rebates would suffer from the negative halo from traditional rebates, or benefit as a more entertaining form of rebate. 14 Fourth, while we employed realistic scenarios with a real event – the European Football 20 Championship – the purchase situation was hypothetical. As explained above, because our #1 measurement approach is not incentive-compatible, it may underestimate the absolute 31 effectiveness of both types of promotions studied. In addition, we may underestimate the um e effectiveness of conditional rebates relative to certain rebates because we do not capture effects Vo l of the advertising that often accompanies conditional rebates. We also ran our study one year R M before the actual event, so response in our study is probably less emotional than in practice. g IJ Thus, our findings on the effectiveness of conditional rebates may be conservative, and it would m in be worthwhile to validate them with field data. rth co Fifth, we rely on the information in self-stated probabilities and use a probability Fo weighting function to transform them into subjective probabilities. Future researchers could design a study and gather data that permit the direct estimation of consumers’ subjective probabilities. Overall, our findings are that conditional rebates can be modeled at the level of the consumer utility function, response to them is highly heterogeneous, and they provide a viable alternative to traditional rebates. We urge further research on uncertain promotions in general, and on conditional rebates in particular as a promising form of promotion. 35 REFERENCES Alloy, L. B., & Abramson, L. Y. (1988). 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Journal of Fo Marketing Research, 46(6), 816–831. 41 Table 1 EXAMPLES OF CONDITIONAL REBATES Name of Company Year Product Category Country Nature of External Event 1998 U.S. Sun rooms, spas, and gazebos Sports: Minnesota Vikings win last five games of year by 7 points or more (football) BrandsMart 1999 U.S. Electronics Sports: Kansas City Chiefs beat San Diego Chargers on Halloween (football) Epson 2003 Multiple Printer Sports: Home nation wins rugby World Cup Canandaigua Wine Company 2003 U.S. Champagne Weather: ≥ 4 inches of snow on New Year’s Day Media Markt 2004 Germany TV Sports: Germany wins soccer EURO Hipercor 2004 Spain Electronics Sports: Spain wins soccer EURO Bayerische Hypo- und Vereinsbank AG 2006 (yearly) Germany Savings account Media Markt 2006 Germany TV Media Markt 2006 Italy TV Ashley Furniture HomeStore 2007 U.S. Furniture Furniture & Appliance Mart 2007 U.S. Jordans’ Furniture 2007 U.S. Springers Jewelers 2007 World Furniture Mall 31 #1 20 14 PanelCraft Inc. IJ R M Vo l um e Sports: FC Bayern Munich scores/becomes German soccer champion Sports: Germany scores in soccer World Cup Sports: Italy wins soccer World Cup Sports: Memphis Tigers win NCCA championship (basketball) Sports: Green Bay Packers win Super Bowl (football) Furniture Sports: Boston Red Sox win World Series (baseball) U.S. Jewelry Weather: ≥ 6 inches of snow on Christmas 2007 U.S. Furniture Sports: Chicago Bears shut-out Green Bay Packers (football) Media Markt 2008 Germany Electronics Sports: Germany scores in soccer EURO final Panasonic 2008 Germany TV Sports: Germany wins Olympics gold PAYBACK Rabattverein 2008 Germany Purchases in partner stores Sports: Germany wins Olympics gold Powerade 2008 U.K. Sports drink Sports: Great Britain wins medal in randomly assigned Olympics event Jordans’ Furniture 2008 U.S. Furniture Sports: Boston Red Sox sweep World Series (baseball) Stacy Furniture 2008 U.S. Furniture Sports: Dallas Mavericks win NBA Finals (basketball) Paradise 2009 Canada Spas, hot tubs Sports: Saskatchewan Roughriders win Grey Fo rth co m in g Furniture, appliances 42 Leisurescapes Cup (football) 2009 U.S. Golf driver Sports: Phil Mickelson or Rocco Mediate wins U.S. Open (golf) Jordans' Furniture 2009 U.S. Furniture Sports: Boston Red Sox sweep World Series (baseball) Simpson Furniture 2009 U.S. Furniture Weather: ≥ 2 inches of snow on January 14, 2010 TomTom 2010 Multiple GPS Sports: Home nation wins soccer World Cup Currys 2010 England TV Sports: England scores in soccer World Cup Nationwide 2010 England Bond Sports: England wins soccer World Cup Trafalgar Wharf 2010 England Boat storage Sports: Andy Murray wins Wimbledon (tennis) Toshiba 2010 Multiple Laptop, TV Sports: Home nation wins soccer World Cup Carrefour 2010 France TV Sports: France advances at least to semi-final in soccer World Cup Saturn 2010 France TV Sports: France wins soccer World Cup Media Markt 2010 Germany TV Sports: Germany advances at least to round of last 16 in soccer World Cup Banesto 2010 Spain Deposit account Sports: Spain wins soccer World Cup Media Markt 2010 Spain TV, projector or TFT monitor Sports: Spain wins soccer World Cup without losing Pc City 2010 Spain TV Sports: Spain scores in soccer World Cup Slovenian tourist board 2010 U.K. Golfsmith 2010 U.S. Perry’s Emporium 2010 U.S. Tom Kadlec Honda 2010 Trafalgar Wharf 2011 M Vo l um e 31 #1 20 14 Golfsmith IJ R Trip to Slovenia Sports: Slovenia advances at least to quarterfinal in soccer World Cup Sports: Phil Mickelson wins Masters (golf) Jewelry Weather: ≥ 3 inches of snow on Christmas U.S. Cars Weather: ≥ 5 inches of snow on Christmas England Boat storage Sports: England wins rugby World Cup 2011 England Boat storage Weather: ≥ 1 inch of snow on Christmas Victor Chandler 2011 U.K. Sports bets Sports: Andy Murray wins Wimbledon (tennis) Jordans’ Furniture 2011 U.S. Furniture Sports: Boston Red Sox player hits homerun on Jordans' sign (baseball) Mysportworld 2012 Germany Sports goods Sports: Germany wins soccer EURO PAYBACK Rabattverein 2012 Germany Purchases in partner stores Sports: Germany wins Olympics gold Cadbury 2012 U.K. Chocolate bars Sports: Randomly assigned British athlete wins Olympics medal Santander 2012 U.K. Bank account Sports: Rory McIllroy wins a “Major” (golf) in m rth co Fo Trafalgar Wharf g Golf driver 43 Table 2 ATTRIBUTES IN THE CONJOINT TASK Washing Machines TV - Bosch - AEG - Sony - Philips Quality Rating of washing performance by Stiftung Warentest: - Good (2.3) - Satisfactory (2.7) Rating of picture quality by Stiftung Warentest: - Good (2.3) - Satisfactory (2.7) Promotion - - Fo rth co m in g IJ R M 20 #1 None Rebate 30 € Rebate 60 € Rebate 90 € Conditional rebate 150 € Conditional rebate 300 € Conditional rebate 450 € 31 e Vo l um None Rebate 30 € Rebate 60 € Rebate 90 € Conditional rebate 150 € Conditional rebate 300 € Conditional rebate 450 € 14 Brand 44 Table 3 MEASUREMENT SCALES FOR CONCOMITANT VARIABLES Items Reference Alpha Savings benefit Conditional promotions let me save money. … allow me to spend less. Chandon, Wansink, and Laurent (2000) .73 Entertainment benefit … are fun. … are entertaining. Chandon, Wansink, and Laurent (2000) .86 Thinking costs ... are hard to figure out. … require a lot of thinking. Involvement with event The performance of the German team in the European Football Championship 2012 is very important to me. I am very interested in how well the German team does in the European Football Championship 2012. Gambling proneness I like to gamble. I like to take risks. 14 .68 .91 Burton et al. (1998) .91 Fo rth co m in g IJ R M Vo l um e 31 #1 20 Steenkamp, van Heerde, and Geyskens (2010) 45 Table 4 DESCRIPTIVE STATISTICS TV (n = 271) Respondents with rebate experiencea 12.6% 15.9% Respondents with conditional rebate experiencea 6.5% 6.3% 58% (26) 20 Mean stated probability of event 14 Washing Machines (n = 293) 57% (25) 2.9 (1.1) Mean entertainment perception 2.8 (1.2) 2.7 (1.2) Mean thinking perception 2.5 (1.1) 2.5 (1.1) um e 31 #1 Mean savings perception 3.2 (1.4) Vo l Mean involvement with event M Mean gambling proneness IJ R Males in g Mean age rth co m Mean household income (€/month) 2.9 (1.1) 3.1 (1.4) 2.4 (1.1) 2.4 (1.1) 48.5% 50.7% 45.2 (14.8) 47.7 (15.6) 2,495 (1,261) 2,640 (1,334) 52.7% 43.7% Employed part time 14.1% 16.7% Unemployed 33.2% 39.6% College degree 34.1% 37.0% High school degree (Abitur) 24.6% 21.1% Secondary degree 41.3% 41.9% Fo Employed full time Standard deviations are in parentheses where necessary. a % of respondents who have bought something that had a rebate (conditional rebate) offer in the last 3 years. 46 Table 5 HOLD-OUT COMPARISON WITH BENCHMARK MODELS Model # Param. χ2 a In-Sample LL Hold-Out LL Hold-Out Hit Rate -522.29 .728 B1: No promotion (β2, β3, β4, β5 = 0) 18 -1,062.00 B2: Common discount parameters (β2 = β4, β3 = β5, pc = stated prob.) 24 -968.56 168.88*** (vs. B1) B3: No probability weighting (pc = stated prob.) 30 -923.02 PM: Proposed model 33 -918.03 14 Washing Machines .775 91.08*** (vs. B2) -460.04 .793 9.98** (vs. B3) -468.16 .790 Vo l um e 31 #1 20 -482.55 M TV 18 -1,053.27 -344.11 .786 IJ R B1: No promotion (β2, β3, β4, β5 = 0) 24 -968.03 170.48*** (vs. B1) -327.99 .811 B3: No probability weighting (pc = stated prob.) 30 -950.13 35.80*** (vs. B2) -302.38 .827 33 -941.68 16.90*** (vs. B3) -301.17 .830 Fo rth co m in g B2: Common discount parameters (β2 = β4, β3 = β5, pc = stated prob.) PM: Proposed model Estimation on 200 respondents for each category Hold-out analysis on 93 respondents for washing machines and 71 for TVs. a Likelihood ratio improvement of in-sample LL (nested models); ** p < .05. *** p < .01. 47 Table 6 MODEL PARAMETERS FOR WASHING MACHINES β3 Conditional rebate discount parameter β5 Conditional rebate discount2 parameter α Weighting parameter for stated probability of event sp Mean stated probability p Mean transformed probability REB R (60) Arrow-Pratt index for rebate of 60€ CR R (300) Arrow-Pratt index for conditional. rebate of 300€ η Segment size γ0 Constant rth co m in g IJ R M Vo l β4 Impact of savings benefit γ2 Impact of entertainment benefit γ3 Impact of thinking costs γ4 Impact of involvement with event γ5 Impact of gambling proneness * Fo γ1 14 Certain rebate discount parameter Certain rebate discount2 parameter 20 β2 #1 Quality valuation -.83*** (.24) .46 ** (.23) 3.22 ** (1.43) -1.37 (1.36) 2.92 *** (.96) -.30 (.18) .30 * (.16) .65 .47 1.04 31 β1 -.09 (.14) 3.47 *** (.24) 4.07 *** (1.34) -1.99 (1.41) 2.10 *** (.54) -.22 ** (.11) .48 *** (.18) .56 .49 1.42 e Brand preference for Bosch Segment 2 Estimate (SE) um β0 Segment 1 Estimate (SE) 1.69 1.61 .58 1.00 *** (.22) -.04 (.19) -.39* (.20) -.46 ** (.20) -.40 * (.21) .12 (.20) .18 -.29 (.43) .02 (.26) -.16 (.27) -.78 ** (.31) -.15 (.34) .35 (.30) p < .10 ** p < .05 *** p < .01 p and η computed based on parameter estimates for α and γ0-γ5 respectively. Discount divided by 100 to facilitate the estimation. Segment 3 Estimate (SE) .80*** (.15) .26** (.11) 4.96*** (.89) -3.21*** (.96) -.06 (.39) .14 (.09) .00 (.54) .57 .37 3.48 -1.08 .24 ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ 48 Table 7 MODEL PARAMETERS FOR TV β3 Conditional rebate discount parameter β5 Conditional rebate discount2 parameter α Weighting parameter for stated probability of event sp Mean stated probability p Mean transformed probability REB R (60) Arrow-Pratt index for rebate of 60€ CR R (300) Arrow-Pratt index for conditional rebate of 300 € η Segment size γ0 Constant rth co m in g IJ R M Vo l β4 Impact of savings benefit γ2 Impact of entertainment benefit γ3 Impact of thinking costs γ4 Impact of involvement with event γ5 Impact of gambling proneness * Fo γ1 14 Certain rebate discount parameter Certain rebate discount2 parameter 1.05*** (.14) .60*** (.16) 4.60*** (1.05) -2.27** (1.12) .60 (.40) -.05 (.08) 1.00 (.89) .48 .48 1.45 20 β2 -.82*** (.12) .48*** (.12) 1.40 (.87) .16 (.93) 2.82*** (.55) -.30** (.12) .00 (.09) .62 .37 -.12 #1 Quality valuation .15 (.22) 3.44 *** (.28) 1.69 (1.68) -.96 (1.79) .95 (.83) -.07 (.17) .24 (.38) .56 .42 2.14 31 β1 Segment 3 Estimate (SE) e Brand preference for Sony Segment 2 Estimate (SE) um β0 Segment 1 Estimate (SE) .79 1.76 1.00 .51 .90 *** (.25) .18 (.21) .30 (.21) -.41 ** (.20) .10 (.21) .00 (.21) .26 .13 (.28) .46* (.24) .42* (.24) -.25 (.24) .40 (.25) .38* (.23) .23 ⎯ p < .10 ** p < .05 *** p < .01 p and η computed based on parameter estimates for α and γ0-γ5 respectively. Discount divided by 100 to facilitate the estimation. ⎯ ⎯ ⎯ ⎯ ⎯ Certain Reward 49 Temporary price reductions Multi-item promotions Figure 1 Traditional mail-in rebates TYPES OF PROMOTIONS Coupons Free gifts/samples ate Reward Delayed Reward Contests Instant win sweepstakes Sweepstakes 14 Tensile promotions (X% - Y% off) #1 20 Conditional rebates (Buy now, get Y% off if Z happens) Fo rth co m in g IJ R M Vo l um e 31 Uncertain Reward Which HDTV would you rather buy? 50 Fo rth co m in g IJ R M Vo l um e 31 #1 20 14 Figure 2 EXAMPLE OF A CHOICE TASK 51 Fo rth co m in g IJ R M Vo lu m e 31 #1 20 14 Figure 3 MARKET SHARE SIMULATIONS: SEGMENT LEVEL Note: TV Segment 3 is not shown because its discount parameters are such that even very high CR discounts cannot recoup base market share. 52 Fo rth co m in g IJ R M Vo lu m e 31 #1 20 14 Figure 4 MARKET SHARE SIMULATIONS: OVERALL SAMPLE Note: All segments are included in these simulations. 53 Appendix MODEL IDENTIFICATION SIMULATIONS Simulation 1 Segment 1 Est. TV SV Est. TV SV Est. -.08 -1.19 -.04 √ -.78 -.24 -.62 √ .88 1.17 .97 √ β1 3.41 4.18 3.63 √ .36 -.22 .27 √ .24 .26 .40 √ β2 3.88 6.61 4.14 √ 3.65 5.36 3.73 √ 4.98 6.84 4.61 √ β3 -1.82 -1.22 -1.82 √ -1.77 -3.07 -1.84 √ -3.23 -2.06 -3.25 √ β4 2.09 2.16 2.58 2.55 4.00 2.37 √ -.07 -.56 -.72 √ β5 -.22 -.44 -.42 -.22 .29 α .20 1.40 .13 √ .33 γ0 .96 .26 1.07 √ -.19 √ .13 .45 .00 √ -.78 .22 √ .00 -1.43 .00 √ -.94 .09 √ ⎯ ⎯ ⎯ Vo l um -.42 e #1 20 β0 14 SV Segment 3 31 TV Segment 2 R M Simulation 2 TV SV Est. √ 2.00 3.51 1.96 Segment 3 TV SV Est. √ -2.00 -2.38 -2.15 √ .00 1.23 β1 .00 .92 .00 √ -2.00 -3.80 -2.00 √ 2.00 2.30 1.93 √ β2 2.00 1.99 2.01 √ 3.00 2.89 3.17 √ .00 -1.41 .06 √ β3 -1.00 .16 -.97 √ -2.00 -1.02 -1.96 √ .00 -.51 .06 √ β4 2.00 1.11 1.91 √ -3.00 -2.88 -3.66 √ 2.00 1.42 2.21 √ β5 -1.00 -2.07 -1.00 √ .00 1.20 .44 -1.00 -2.05 -.76 α .50 1.00 .55 √ .10 -.40 .23 √ .01 -.03 .00 γ0 .80 .87 .78 √ -.80 -2.14 -.84 √ ⎯ ⎯ ⎯ m β0 Fo .03 g Est. in SV Segment 2 rth co TV IJ Segment 1 √ TV = true value; SV = starting value; Est. = estimate; √ = estimate within 1 std. error of the true value.
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