自1970年以來,婦女在安排工作和子女照料時間之間的不兼容性(incompatibility),成為解釋眾多已開發國家陷入低生育趨勢的重要依據。採用母親照料之外的照料方式,如專業機構及祖父母照料,可放寬母親所面對之工作與生育的時間限制,緩解兩類時間利用的不兼容性,並對家庭的生育決策帶來促進作用。而在家庭可得的照料途徑中,以祖父母的健康狀況作為衡量祖父母照料是否可得的一個重要指標,仍然缺乏相關的實證分析。有鑒於此,本文利用華人家庭動態資料庫(the Panel Study of Chinese Family Dynamics,簡稱PSFD)2004自2011年的數據, 並建立家庭生育決策的逐次常態機率模型(Sequential probit model),以分析祖父母健康水平對家庭生育決策的影響。 實證結果顯示,不同年齡層次的祖父母會給家庭的生育決策帶來不同的影響,只有年齡層在55到64歲之間的健康祖父母才會對家庭的生育決策造成正向的影響。除此之外,相對於全體祖父母而言,55到64歲的祖母和外祖母在家庭的生育決策中則有著更大的正向影響,從而說明了女性在照料後代中的重要地位。
The incompatibility of female time allocation between labor supply and child care has been the main explanation of low fertility rate in developed countries since 1970s. By relaxing wives’ time restriction, non-maternal care especially those from grandparents or formal care, alleviates this problem and thus permits household to have more children. Grandparents’ health condition is one of the key elements used to evaluate the availability of non-maternal childcare. However, only limited studies signified and measured its influence on family fertility decision. Based on the Panel Study of Chinese Family Dynamics (PSFD) from 2004 to 2011, this study examines the effect of grandparents’ health on household fertility decisions in Taiwan using a sequential probit model. Empirical results suggest grandparents’ health condition has different impacts depending on the elders’ age. Only family having healthy grandparents between 55-64 years old will the availability of grandparents positively influence family’s desire to have more children. Moreover, it is found that the number of healthy grandmothers aged 55-64 has a larger effect compared with the total number of healthy grandparents, which reveals the important role of female in childcare.