是什麼因素會影響同化與對比的效果產生？和已往社會心理學領域有不同的研究。
Higgings(1997)提出模擬兩可、相似的刺激會產生同化效果 （1977）。Paul M. Herr, Steven J. Sherman, and Russel H. Fazio.(1982)發現當目標物是溫和的刺激物時，造成評比結果是相似的；但若是極端的刺激物時，會產生對比效果。本研究目的為討論同化和對比度的影響。結果發現，我們可使用模糊性和j極端性為因素來達成結果。

How assimilation and contrast effects are occurs, what are the factors that influence assimilation or contrast effects to be occurred? There are various previous research in the field of Social Psychology, for example, as ambiguous stimuli, priming with moderately extreme exemplars of a category appearing to produce assimilation effects which is consistent with that proposed by Higgings et al. (1977).In 1982, in a consequence of priming: Assimilation and Contrast effects by Paul M. Herr, Steven J. Sherman, and Russel H. Fazio., they found that their ratings were assimilated to the primed anchor when subjects were primed with moderately extreme levels (of small or large animals). If extremely large or extremely small animals were primed, a contrast effect would be occurred. Regarding to the related research as mentioned above, this current study will focus on the assimilation and contrast effects. We will find out the results by using two variables: ambiguity and extremity to determine the results.

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