• Adding exchange to charity: a reference price explanation

      Briers, Barbara; Pandelaere, Mario; Warlop, Luk (Journal of Economic Psychology, 2007)
      Charities often request donations while offering a near-worthless token, like a key chain, in exchange. Little research has examined whether such ‘exchange’ requests are met with higher compliance rates than simply asking people to donate. Our studies suggest that in simple donation settings people may have difficulties in estimating a socially acceptable donation amount and therefore prefer opportunities that provide them with an anchor price. The value of a material good in a donation setting can play this anchoring role and signal a reference price. To the extent that the suggested reference price is low enough, exchange requests lead to more compliance than simple donation requests. However, our results indicate that, when accompanied by specified amounts, simple donation requests result in even better compliance rates than exchange requests.
    • Better think before agreeing twice. Mere agreement: a similarity-based persuasion mechanism

      Pandelaere, Mario; Briers, Barbara; Dewitte, Siegfried; Warlop, Luk (International Journal of Research in Marketing, 2010)
      The present paper shows that the frequency of people's compliance with a request can be substantially increased if the requester first gets them to agree with a series of statements unrelated to the request but selected to induce agreement. We label this effect the ‘mere-agreement effect’ and present a two-step similarity-based mechanism to explain it. Across five studies, we show that induced mere agreement subtly causes respondents to view the presenter of the statements as similar to themselves, which in turn increases the frequency compliance with a request from that same person. We support the similarity explanation by showing that the effect of agreement on compliance is suppressed when agreement is induced to indicate dissimilarity with the interviewer, when the request is made by some other person, and when the artificially high level of agreement is made salient. We also validate the practical relevance of the mere-agreement persuasion technique in a field study. We discuss how the mere-agreement effect can be broadly used as a tool to increase cooperation and be readily implemented in marketing interactions.
    • How to make a 29% increase look bigger: the unit effect in option comparisons

      Pandelaere, Mario; Briers, Barbara; Lembregts, Christophe (Journal of Consumer Research, 2011)
      Quantitative information can appear in different units (e.g., 7-year warranty = 84-month warranty). This article demonstrates that attribute differences appear larger on scales with a higher number of units; expressing quality information on such an expanded scale makes consumers switch to a higher-quality option. Testifying to its practical importance, expressing the energy content of snacks in kilojoules rather than kilocalories increases the choice of a healthy snack. The unit effect occurs because consumers focus on the number rather than the type of units in which information is expressed (numerosity effect). Therefore, reminding consumers of alternative units in which information can be expressed eliminates the unit effect. Finally, the unit effect moderates relative thinking: consumers are more sensitive to relative attribute differences when the attribute is expressed on expanded scales. The relation with anchoring and implications for temporal discounting and loyalty programs are discussed.
    • Hungry for money: The desire for caloric resources increases the desire for financial resources and vice versa

      Briers, Barbara; Pandelaere, Mario; Dewitte, Siegfried; Warlop, Luk (Psychological Science, 2006)
      This report attempts to provide an evolutionary explanation for humans' motivation to strive for money in present-day societies. We propose that people's desire for money is a modern derivate of their desire for food. In three studies, we show the reciprocal association between the incentive value of food and of money. In Study 1, hungry participants were less likely than satiated participants to donate to charity. In Study 2, participants in a room with an olfactory food cue, known to increase the desire to eat, offered less money in a give-some game compared with participants in a room free of scent. In Study 3, participants' desire for money affected the amount of M&M's® they ate in a subsequent taste test, but only among participants who were not restricting their food intake in order to manage their weight.