根據文獻指出，育兒時間對於子女的未來發展影響極大。既有文獻多以最小平方法(ordinary least squares)或是Tobit模型作為研究方法，因而僅能分析育兒時間為平均值的人。此外，既有文獻也未解決育兒時間的實證模型中，薪資於可能為內生的問題。然而，為增加育兒時間並進而提升人力素質，必須關心的是育兒時間較少的人，其育兒時間的決定因素為何。因此本文採用「受限制工具變數分量迴歸模型 (censored quantile instrumental variable model)」為估計方法，利用美國時間運用調查(American Time Use Survey) 2003至2010的個體資料，研究育兒時間的決定因素。實證結果指出，其它種族虛擬變數，在低分量時顯著為負，在高分量時不顯著。顯示政府應針對非西語裔的其它種族，加強宣導育兒的重要性。

Parents’ time on child care has profound impact on children’s human capital formation.  Previous studies on parental time with children, which use ordinary least squares and Tobit model as their estimation method, focus on conditional mean of parental time with children.  As far as we know, no empirical attention has been paid to parents that spent little time with children.  Since wage is likely to be endogenous to time spent with children, this thesis uses censored quantile instrumental variable estimator to analyze the determinants of time spent on child care.  Based on micro data from the 2003-2010 American Time Use Survey, we found that the dummy variable for non-hispanic non-black and non-white is statistically significantly negatively associated with time spent with children.  This result implies that more resources should be directed to facilitating and promoting parental time with children  
among non-hispanic non-black and non-white parents.

目錄
第一章、	緒論	1
第二章、文獻回顧	3
第一節、分量迴歸應用	3
第二節、時間運用應用	4
第三章、研究方法	8
第四章、資料來源與變數定義	11
第一節、資料來源	11
第二節、資料合併過程	11
第三節、變數定義	12
第四節、敘述統計量	13
第五章、實證結果	14
第一節、工具變數相關檢定	14
第二節、受限制工具變數分量迴歸估計結果	15
第六章 結論	20
附錄一:OLS估計結果	58
附錄二:Tobit估計結果	59
附錄三:全部樣本QR估計結果	60
附錄四:女性樣本QR估計結果	61
參考文獻  62

圖目錄
圖4-1　資料合併過程	22
圖5-1　CQIV分量係數:female	23
圖5-2　CQIV分量係數:age	24
圖5-3　CQIV分量係數:age2	25
圖5-4　邊際效果:age	26
圖5-5　CQIV分量係數:merried	27
圖5-6　CQIV分量係數:hagrad	28
圖5-7　CQIV分量係數:somecollege	29
圖5-8　CQIV分量係數:collegegrad	30
圖5-9　CQIV分量係數:advdegree	31
圖5-10　CQIV分量係數:blacknonhisp	32
圖5-11　CQIV分量係數:hispanic	33
圖5-12　CQIV分量係數:otherrace	34
圖5-13　CQIV分量係數:nmchild	35
圖5-14　CQIV分量係數:kids0_5	36
圖5-15　CQIV分量係數:kids6_13	37
圖5-16　CQIV分量係數:finalwage	38
圖5-17　CQIV分量係數:unemployed	39
圖5-18　CQIV分量係數:notinlaborforce	40
圖5-19　CQIV分量係數:newmetsta	41
圖5-20　CQIV分量係數:weekday	42
圖5- 21　CQIV分量係數:unemprate	43
圖5- 22　CQIV分量係數:pci	44

表目錄
表4-1　資料來源	45
表4-2　各項變數定義說明	46
表4-3　敘述統計量	48
表5-1　第一階段估計結果	49
表5-2　第二階段估計結果	50
表5-3　CQIV估計結果	51

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中文部分
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嚴婉禎 (2007)，廠商規模與存活：受限制分量迴歸之應用，中原大學國際貿易學所碩士論文。