對消費者而言，找到理由支持自己的決定是相當常見且重要的，這表示消費者需要藉由決策的合理化，讓自己對所做的決定感到安心。不過，人們不一定總是能夠順利地找到理由支持自己的決定，這是因為在做決定的當下，無法得到足夠的或適當的決策資訊所造成。而在過去的研究中，許多學者討論了消費者在不同購物環境，例如聯合評估或單獨評估下，所面臨到的決策合理化問題與困難，也有研究指出購買不同屬性的產品亦會影響到消費者決策合理化的難易度。本研究認為，購買功能性、享樂性產品所需的資訊與不同購物環境下所突顯的資訊之一致性，會對消費者決策合理化難易度產生影響。當購買功能性產品時，聯合評估會比單獨評估容易合理化決策；相對地，當購買享樂性產品時，單獨評估會比聯合評估容易合理化決策。為了驗證假設，本研究先對相關構面發展量表問卷，再使用情境設計，設計了四種購物情境：在聯合評估或單獨評估下購買功能性產品，在聯合評估或單獨評估下購買享樂性產品。分析335份有效問卷後，其分析結果支持本研究之假設。最後，作者根據研究結果提供若干管理意涵，也對後續研究提出相關建議。

Given reasons for decisions is very common and important for decision makers since people need to justify their decision to be feel relieved and comfortable. However, the justification is not always easy to get because of the lack of sufficient or appropriate information. In the past, several researchers discuss the justification and decision difficulty when people under different purchase context (e.g. joint evaluation or separate evaluation). Besides, some studies point out that different characteristic of product would cause different degrees of ease of justifications. In our research, we propose that purchasing utilitarian or hedonic products would lead people focus on different information, and compatibility of the product information and evaluation mode would affect people’s ease of justification. When people purchase utilitarian products, they feel higher ease of justification in JE than in SE. Likewise, when people purchase hedonic products, they perceive higher ease of justification in SE than in JE. For the sake of examine our hypothesis, we develop related measurement of the concepts, and use scenario experiment design, including four groups of conditions (utilitarian purchase in JE and in SE, hedonic purchase in JE and in SE). There are 335 samples for the final analysis, and the result supports our hypotheses. Lastly, the author provides the several managerial implications for marketers and directions for future researchers.

1. Introduction 1
2. Literature Review 4
2.1 Joint Evaluation (JE) and Separete Evaluation (SE) 4
2.1.1 Preference Reverseal Due to JE and SE 4
2.1.2 Attribute Evaluability in JE and SE 6
2.1.3 Inherently Evaluable and Inherently Inevaluable 7
2.1.4 Thinking and Feeling in Consumer Evaluations 8
2.2 Need for Ease of Justification 9
2.3 Utilitarian and Hedonic Products 11
2.4 Summary 12
3. Research Hypotheses and Methodology 14
3.1 Research Hypotheses 14
3.1.1 Utilitarian Purchase in Joint-Separate Evaluation 16
3.1.2 Hedonic Purchase in Joint-Separate Evaluation 17
3.2 Operational Definition 18
3.2.1 Joint and Separate Evaluation 18
3.2.2 Ease of Justifications 19
3.2.3 Utilitarian and Hedonic Products 19
3.3 Research Methodology 20
3.3.1 Design and Procedure 20
3.3.2 Measurements 23
3.3.3 Pretest 24
4. Formal Survey Analysis and Result 25
4.1 Reliability and Validity Test 27
4.2 Manipulation Check 28
4.3 Hypotheses Test 29
5. Discussion and Implications 33
5.1 Conclusion and Discussion 33
5.2 Managerial Implication 35
5.3 Limitations 37
5.4 Future Suggestions for Future Research 37
Reference 39
Appendix 1. Experimental Product Design Samples 42
Appendix 2. Questionnaire 44

1. Batra, Rajeev and O.T. Ahtola, “Measuring the Hedonic and Utilitarian Sources of Consumer Attitudes,” Marketing Letters, Vol. 2, pp. 159-170, 1990.
2. Bazerman, M. H., Loewenstein, G. F., and White, S. B., “Reversals of Preference in Allocation Decisions: Judging an Alternative Versus Choosing Among Alternatives,” Administrative Science Quarterly, Vol. 37, pp. 220-240, 1992.
3. Bettman, James R. and Kakkar, Pradeep, “Effects of Information Presentation Format on Consumer Information Acquisition Strategies,” Journal of Cousumer Research, Vol.3, pp. 223-240, 1977.
4. Bettman, James R., Luce, Mary Frances, and Payne, John W., “Constructive Consumer Choice Processes.” Journal of Consumer Research, Vol. 25, pp. 187-217, 1998.
5. Chernev, Alexander, “Goal-Attribute Compatibility in Consumer Choice,” Journal of Consumer Psychology, Vol. 14, pp. 141-150, 2004.
6. Chitturi, Ravindra, Rajagopal Raghunathan, and Vijay Mahajan, “Form Versus Function: How the Intensities of Specific Emotions Evoked in Functional Versus Hedonic Trade-Offs Mediate Product Preferences,” Journal of Marketing Research, Vol. 44, pp. 702-714, 2007
7. Connolly, T., and Zeelenberg, M., “Regret in Decision Making,” Current Directions in Psychological Science, Vol. 11, pp. 212-220, 2002.
8. Crowley, Ayn E., Eric R. Spangenberg, and Kevin R. Hughes, “Measuring the Hedonic and Utilitarian Dimensions of Attitudes Toward Product Category,” Marketing Letters, Vol. 3, pp. 239-249, 1992.
9. Davis, Fred D., “Perceived Usefulness, Perceived Ease of Use, and User Acceptance of Information Technology,” MIS Quarterly, Vol.13, pp. 318-340, 1989.
10. Dhar, Ravi and Klaus Wertenbroch, “Consumer Choice Between Hedonic and Utilitarian Goods,” Journal of Marketing Research, Vol.37, pp. 60-71, 2000.
11. Fornell, C. and Larcker, D. F., “Evaluating Structural Equation Models with Unobservable Variables and Measurement Error,” Journal of Marketing Research, Vol. 18, pp. 39-50, 1981.
12. Gregory, R., Lichtenstein, S., and Slovic, P., “Valuing environmental resources: A constructive approach,” Journal of Risk and Uncertainty, Vol. 7, pp. 177-197, 1993.
13. Grether, D. M., and Plott, C. R., “Economic Theory of Choice and The Preference Reversal Phenomenon,” American Economic Review, Vol. 69, pp. 623-638, 1979.
14. Heitmann, M., Lehmann, D. R., and Herrmann, A., “Choice Goal Attainment and Decision and Consumption Satisfaction,” Journal of Marketing Research, Vol. 44, pp. 234–250, 2007.
15. Higgins, E. T., “Beyond Pleasure and Pain,” American Psychologist, Vol. 52, pp. 1280-1300, 1997.
16. Holbrook, M. B. and E.C. Hirschman, “The Experiential Aspects of Consumption: Consumer Fantasies, Feelings, and Fun,” Journal of Consumer Research, Vol. 9, pp. 132-140, 1982.
17. Hsee, C. K., “The Evaluability Hypothesis: An Explanation for Preference Reversals between Joint and Separate Evaluations of Alternatives.” Organizational Behavior and Human Decision Processes, Vol. 67, pp. 247-257, 1996.
18. Hsee, C. K. and Leclerc France, “Will Products Look More Attractive When Presented Separately or Together?,” Journal of Consumer Research, Vol. 25, pp. 175-186, 1998.
19. Hsee, C. K., George Loewenstein, Shally Blount, and Max Bazerman, “Preference Reversals between Joint and Separate Evaluation of Options: A Review and Theoretical Analysis,” Psychological Bulletin, Vol. 125, pp. 576-590, 1999.
20. Hsee, C. K., “Attribute Evaluability and Its Implications for Joint-Separate Evaluation Reversals and Beyond,” Choices, Values and Frames, pp. 543-563, In D. Kahneman & A. Tversky, eds., Cambridge University Press, 2000.
21. Hsee, C. K. and Zhang Jiao, “Distinction Bias: Misprediciton and Mischoice Due to Joint Evaluation.” Journal of Personality and Social Psychology, Vol. 86, pp. 680-695, 2004.
22. Hsee, C. K., Yang, Y., Li, N. and Shen, L., “Wealth, Warmth and Wellbeing: Whether Happiness Is Relative or Absolute Depends on Whether It Is About Money, Acquisition, or Consumption,” Journal of Marketing Research, Vol. 46, pp. 396-409, 2009.
23. Kahneman, Daniel and Shane Frederick, “Representativeness Revisited: Attribute Substitution in Intuitive Judgment,” in Heuristics of Intuitive Judgment: Extensions and Applications, ed. Thomas Gilovich, Dale Griffin, and Daniel Kahneman, New York: Cambrige University Press, 2002.
24. Kleinmuntz, D. N., and Schkade, D. A., “Information Displays and Decision Processes,” Psychological Science, Vol. 4, pp. 221-227, 1993.
25. Lynch, John G., Jr. Dipankar Chakravarti, and Anusree Mitra, “Construct Effects in Consumer Judgments: Changes in Mental Representations or in the Anchoring of Rating Scales?” Journal of Consumer Research, Vol. 18, pp. 1055-1067, 1991.
26. Mano, Haim and Pichard L. Oliver, “Assessing the Dimensionality and Structure of the Consumption Experience: Evaluation, Feeling, and Satisfaction,” Journal of Consumer Research, Vol. 20, pp. 451-466, 1993.
27. Montgomery, Henry, “Decision Rules and the Search for a Dominance Structure: Toward a Process Model of Decision Making,” in Analyzing and Aiding Decision Processes, ed. Patrick Humphreys, Ola Svenson, and Anna Vari, Amsterdam: North-Holland, pp. 343-369, 1983.
28. Nowlis, S. M. and Simonson I., “Attribute-Task Compatibility as a Determinant of Consumer Preference Reversals,” Journal of Marketing Research, Vol. 34, pp. 205-218, 1997
29. Okada, Erica Mina, “Justification Effects on Consumer Choice of Hedonic and Utilitarian Goods,” Journal of Marketing Research, Vol. 42, pp. 43-53, 2005.
30. Piercey, M. David, “Motivated reasoning and verbal vs. numerical probability assessment: Evidence from an accounting context,” Organizational Behavior and Human Decision Process, 108, pp. 330-341, 2009.
31. Sela Aner, Johan Berger, and Wendy Liu, “Variety, Vice, and Virtue: How Assortment Size Influence Option Choice,” Journal of Consumer Research, Vol.35, pp. 941-951, 2009.
32. Shafir, Eldar, Daniel N. Osherson, and Edward E. Smith, “The Advantage Model: A Comparative Theory of Evaluation and Choice Under Risk,” Organizational Behavior and Human Decision Processes, Vol. 55, pp. 325-378, 1993.
33. Shafir, E., Simonson, I., and Tversky, A., “Reason-Based Choice,” Cognition, Vol. 49, pp. 11-36, 1993.
34. Simonson, Itamar, “Choice Based on Reasons: The Case of Attraction and Compromise Effects Source,” Journal of Consumer Research, 16 (Sep), pp. 158–74, 1989.
35. Strahilevitz, Michal and John G. Myers, “Donations to Charity as Purchase Incentives: How Well They Work May Depend on What You Are Trying to Sell,” Journal of Consumer Research, Vol. 24, pp. 434-446, 1998.
36. Tversky, A., “Intransitivity of Preference,” Psychological Review, Vol. 76, pp. 31-48, 1969.
37. Tversky, A., Sattath, S., and Slovic, P., “Contingent Weighting in Judgment and Choice,” Psychological Review, Vol. 95, pp. 371-384, 1988.
38. Voss, Kevin E., Eric R. Spangenberg, and Bianca Grohman, “Measuring the Hedonic and Utilitarian Dimensions of Consumer Attitude,” Journal of Marketing Research, Vol. 40, pp. 310-320, 2003.
39. Wirtz, J. and Lee M. C., “An Examination of the Quality and Context-Specific Applicability of Commonly Used Customer Satisfaction Measures,” Journal of Service Research, Vol. 5, pp. 345-355, 2003.