本文以《臺灣長期教育追蹤資料庫》的合併資料為研究對象,旨在探討家庭手足人數對學習成績的影響,其次探討族群間的差異。首先,初步檢視敘述統計資料,發現家庭手足人數與成績表現有明顯反向關係,且外省族群有最好的社經背景與最低的平均生育人數,原住民族群社經背景最差而且平均手足人數最多。第二,以最小平方法分析,將學習成績對手足人數及其他控制變數做迴歸分析,發現手足效果仍非常明顯;在控制社經背景變數後,外省族群子女學習成績並沒有比閩客族群高,然原住民族群仍明顯落後於其他族群。同時,本文透過「是否有異性手足」作為「手足人數」的工具變數,進行兩階段最小平方法迴歸分析,試圖解決手足人數的內生性問題。第三,透過中介變數對社經背景做複迴歸分析,除了發現手足排擠學習機會外,進一步發現父母傾向對兒子投資私立國中資源,對女兒投資才藝班訓練,可能為評估投資報酬率後之結果;又原住民族群子女與父母同住比例最低,父母親的酗酒比例最高,兩者均有礙子女社會資本養成,可能為原住民子女表現遜於其他族群的原因之一。
The research target of this thesis is the merge data from 《Taiwan Education Panel Survey》,it aims at investigating the effect of number of siblings on the learning achievements.The paper also explores the differences between different ethnic groups.First of all,after examining the statistics information,it is found that the number of siblings and education accomplishment are adversely related.In addition,Mainlanders have the best social financial status yet got the lowest give birth rate;while aboriginals have the worst societal economic status but got more number of family members.Second,the paper uses the ordinary least square method to analyze data,it uses the regression analysis for the educational achievement with sibling numbers and other control variables.It is discovered that the influence of sibling is very recognizable.After controlling the socio-economic background variables,we can see that the learning achievement of Mainlanders are not better than the aboriginals.However, Aboriginal groups still significantly lagging behind other ethnic groups.At the same time, this thesis also uses "Sibling with different sex" as the instrument variable of "Number of Siblings".I have applied two stages of 2SLS method, aim to solve the problem of endogeneity of number of siblings.Third,I have done the multiple regression analysis through intermediary variables upon socio-economic background,other than discovering siblings' crowd out learning opportunities,I further found out that parents tend to allocate resources on sons for private schools,whereas investment for daughters is on talent interest class,this might be the outcome for the anticipated return on investment.Aboriginals' child living with their parents have the lowest percentage however they have the highest percentage that parents are alcoholism,this will both hinder the social capital for their children.And this would be one of the reasons that performance of aboriginals are worse than other ethnic groups.