本文討論同居的生育意涵，並利用台灣2000年戶口普查與戶籍登記之婚姻狀況分佈差距，以及普查資料中的家戶成員關係，來估計台灣的同居概況。我們總共提出來三個同居人數的估計值，分為別203,720人、379,776人、與440,508人。即使是最高估計，就目前的社會狀況來說（晚婚、婚前性行為、離開父母家庭的比率增高），似乎偏低。我們檢討各種可能的原因，同時提出未來相關調查的修改建議：在婚姻狀況變項上「有偶」與「同居」分開，在與戶長關係變項上將「配偶」與「同居人」分開，而如果顧慮同居者不會據實回答，則乾脆取消同居與同居人選項，而在與戶長關係上增加一類「男／女朋友」。

In most Western countries cohabitation began when marriage rates declined. The marriage rate in Taiwan is declining while the prevalence of cohabitation is still ambiguous. This paper clarifies the fertility implication of cohabitation and estimates the number of cohabitation in Taiwan. There estimates of cohabiting persons, 203720, 379776, and 440508, which were based on 2 approaches by using the census 2000 data set, were proposed. Even though the highest estimate, it is likely to be underestimated amid the Taiwan’s background of marriage postponement, popular pre-marital sex, and higher proportion of leaving parental home. To getting better cohabitation information, a questionnaire strategy was suggested.

同居; 生育; 參照者; 伴侶; 普查

cohabitation; fertility; reference person; artner; census