企業界常認為共同品牌策略是為其獲取更高利潤的良好方法，尤其當新品牌產品推出時，常希望透過共同品牌策略，藉助在消費者心中評價高之品牌聲望的拉抬，為自身品牌創造更多正面效果。但少有人考慮到，這樣的合作方式是否會影響原本評價高之品牌在消費者心中的地位，因此本研究欲探討在共同品牌情境下，消費者是否仍對高評價之品牌維持正面的評價。
本研究以過去情境效果的相關理論為基礎，獲得互動假設在共同品牌策略下的實證，亦即當目標品牌（預設其為評價中等品牌）受到情境品牌（預設其為高評價品牌）的影響，使消費者對其評價產生同化或對比效果時，情境品牌也會同時受到目標品牌的反向作用影響，使消費者又對情境品牌的評價產生同化或對比效果。本研究的實驗結果發現，情境品牌評價之同化、對比效果取決於：目標品牌是否包括情境品牌的優勢、目標品牌與情境品牌之間品質分數的解釋範圍有否重疊。這意謂著，當評價中等之品牌與評價高的品牌合作時，在以上兩種情況下，反而會使高評價品牌降低其在消費者心中的地位，進而獲得更差的品牌評價。因此，高評價品牌必須注意與合作對象推出共同品牌產品，提昇對方評價的同時，會造成本身品牌評價降低的危機。

Marketers often think that co-branding is a good strategy to bring benefits for their brands, especially the neutrally perceived brand likes to release new products with a positively brand logo. Would consumers’ evaluation toward positively perceived brands be influenced under co-branding strategy? Fewer people discuss this situation. Therefore, in this study we want to know if a positively perceived brand can still be evaluated so positively after co-branding?
The present study uses Reciprocity Hypothesis, an extended application of context effect, to examine under what condition the consumers’ judgments of positively perceived brand will be influenced by the neutrally perceived brand and assimilation or contrast effect will occur when context and target brands work together under co-branding. As a result, the findings of experiments in the present study demonstrated that when positive brand was a piece of information included in the neutral brand, and there was an overlap between the interpretation of positive and neutral brand in product quality, assimilation will occur. That is, under above conditions, the positive brand would be evaluated less positive. However, under the other conditions, such as that when positive brand was the information excluded in the neutral brand, and there was a non-overlap between the interpretation of positive and neutral brand, the contrast will occur. Therefore, when marketers of positively perceived brands cooperate with those of neutrally brands through co-branding strategy, they need to consider carefully to avoid brand dilution happening.

Herr, Paul M. (1989). Priming Price: Prior Knowledge and Context Effects. Journal of Consumer Research, 16 (June), 67-75.
Herr, Paul M, Steven J. Sherman, & Russell H. Fazio (1983). On the Consequences of Priming: Assimilation and Contrast Effect. Journal of Experimental Social Psychology, 19, 323-340.
Higgins E. T. & C. M. Brendl (1995). Accessibility and Applicability: Some “Activation Rules” Influencing Judgment. Journal of Experimental Social Psychology, 31, 218-243.
Higgins E. T, W. S. Rholes, & C. R. Jones (1977). Category Accessibility and Impression Formation. Jornal of Experimental social Psychology, 13, 141-154.
Hsiao C. C. (2002). The Reciprocity Hypoesis as a Explanation of Perception Shifts in Product Judgment. Unpublished doctorial dissertation, Purdue University, West Lafayette, Indiana.
Hsiao C. C & Y. W. Chien (2001). Dimensional Overlap Model for Explanation of Contextual Priming Effects. Advances in Consumer Research, 28, 136.
Huber, J. & J. McCann (1982). The Impact of Inferential Beliefs on Product Evaluations. Journal of Marketing Research, 19, 324-333.
Jagacinski, C. M. (1994). Evaluation of Job Candidates with Missing Information: Effects of Attribute Importance and Interattribute Correlation. Journal of Behavioral Decision Marketing, 7, 25-42.
Johnson, R.D. (1988). Making Decisions with Incomplete information: The First Complete Test of the Inference Model. In T. Shrull (Ed.), Advances in Consumer Research, 16, 522-528. Provo, UT: Association for Consumer Research.
Johnson, R.D. & I. P. Levin (1985). More than Meets the Eye: The Effect of Missing Information on Purchase Evaluations. Journal of Consumer Research, 12, 169-177.
Kardes, F. R. & D. M. Sanbonmatsu (1993). Direction of Comparison, Expected Feature Correlation, and the Set-size Effect in Preference Judgment. Journal of Consumer Psychology, 2, 39-54.
Levin, A. M., J. C. Davis, & I. P. Levin (1996). Theoretical and Empirical Linkages between Consumers’ Responses to different Branding Strategies. In K. Corfman & J. Lynch (Eds.), Advances in Consumer Research, 23, 296-300. Provo, UT: Association for Consumer Research.
Levin, I. P.& A. M. Levin (2000). Modeling the Role of Brand Alliances in the Assimilation of Product Evaluations. Journal of Consumer Psychology, 9 (1), 43-52.
Levin, I. P., D. P. Chapman, & R. D. Johnson (1988). Confidence in Judgments Based on Incomplete Information: An Investigation Using Hypothetical and Real Gambles. Journal of Behavior Decision Making, 1, 29-41.
Levin, I. P., R. D Johnson, & S. V. Faraone (1984). Information Integration in Price-quality Tradeoffs: The Effects of Missing Information. Memory and Cognition, 12, 96-102.
Meyers-Levy & Sternthal (1993) A Two-factor Explanation of Assimilation and Contrast Effects. Journal of Marketing Research, 30, 359-368.
Rao, A. R., & R. W. Ruekert (1994). Brand alliances as signals of product quality. Sloan Management Review, 36, 87-97.
Rao, A. R., L. Qu, & R. W. Ruekert (1999). Signaling Unobservable Quality Through a Brand Ally. Journal of Marketing Research, 36, 258-268.
Schwarz, N., & Bless, H. (1992). Constructing Reality and its Alternatives: Assimilation and Contrast Effects in Social Judgment. In L. L. Martin & A. Tesser (Eds.). The construction of social judgments. 217-245. Hillsdale, NJ: Erlbaum.
Stapel, D.A., & Schwarz, N. (1998). The Republican Who Did Not Want to Become President: An Inclusion/exclusion Analysis of Colin Powell's Impact on Evaluations of the Republican Party and Bob Dole. Personality and Social Psychology Bulletin, 24, 690-699.
Stapel, D.A., Willem Koomen, & Aart S. Velthuijsen (1998). Assimilation or Contrast?: Comparison Relevance, Distinctness, and the Impact of Accessible Information on Consumer Judgment. Journal of Consumer Psychology, 7 (1), 1-24.
Tversky, Amos (1977). Features of Similarity. Psychological Review, 84 (July), 327-352.
Wu, Y. C. (2007). Context Effect in Co-branding Judgments. Unpublished master’s thesis, National Tsing Hua University, Taiwan, R.O.C.