本文旨在探討使用「基因改造(GMO 'genetically modified organisms)大豆原料」的產品屬性與其他產品屬性如「品牌」及「價格」在消費者購買豆腐產品上之相對重要性，並據以進行市場區隔分析。利用2004年9月的一項台灣地區基因科技意向大型調查計畫資料，我們採用聯合（屬性）分析法(conjoint analysis)，估算上面三項豆腐屬性之成份效用值及相對重要性。結果發現：平均而言，消費者在購買豆腐之決策上，最重視「品牌」屬性，次爲「是否使用GMO大豆原料」屬性，最後爲「價格」；不過，不同偏好結構之消費群，其重視之次序則有差異。根據消費者對各屬性之偏好差異，我們利用集群分析法(cluster analysis)將全樣本分爲三個次樣本群，依各群屬性相對重要性命名，第1群消費者視爲「一般」消費群、第2群視爲「喜好非GMO」消費群、第3群則稱爲「喜好GMO」消費群，並進行市場區隔分析研究。研究發現性別、年齡、教育程度、對GMO食品風險感受、與對市售豆腐是否會GMO原料屬性之認知等變數爲消費決策之重要決定因子。相對於一般消費群，「喜好非GMO」之消費群擁有：女性、年齡較高、教育水準較高、認爲GMO食品不安全、對市售豆腐GMO特性認識高等特性。至於「喜好GMO」消費群，則爲那些不認爲GMO食品爲不安全的消費群，這些人那多爲購買頻率較高考。若比較後二群消費者，那可發現「喜好非GMO」群相對股「喜好GMO」群間之差異爲：前者在年齡、教育程度、對GMO食品不安全感興對市售豆腐GMO特性之了解程度等特性，都較後者爲高。

The purpose of this study is to find the relative importance for attributes of tofu in Taiwan. Market segments are identified based on a cluster analysis of respondents' preferences for brand, price, and GMO content. Conjoint analysis is used to elicit consumer preference for attributes. Part worth and relative factor importance scores are estimated for each attribute. On average, brand is the most important attribute in terms of its influence on consumer preference, this is followed by GM content (GM soybean) in tofu, and price is the last. According to the preference structure of consumers, cluster analysis was used to segment respondents into three groups. They are designated General Buyers, Non-GMO Buyers and GMO Buyers. In addition, a multinominal logit model is performed to determine whether respondents in different segment differed by socioeconomics characteristics. Comparing N on-GMO Buyers and GMO Buyers, we found that those respondents who are female, older, higher educated, believe that GMOs are not safe, and better knowledgeable about the characteristics of GMO tofu are likely to be non-GMO tofu buyers.