Factors Influencing Birth Spacing From The Perspective Of Survival Analysis

In 2020,the number of births in Taiwan fell short of the number of deaths for the first time,resulting in a negative population growth.In the same year,only 12 million people were born on the mainland,the lowest number since 1960.The total fertility rate for women of childbearing age is already low,at 1.3.The Political Bureau of the CPC Central Committee announced the "three-child policy" at the meeting on population aging in May2021,which indicates that the "two-child" effect is gradually weakening and the problem of population aging in China is becoming increasingly prominent.In the context of widespread social concern and discussion about low fertility rate,this thesis focuses on family birth spacing.As an important social and cultural phenomenon,fertility itself has three different dimensions of quantity,time and gender.For families with more than 2 children,the determination of birth interval is one of the important embodiments of the attribute of birth time dimension.Due to the influence of various family planning policies in Chinese mainland,the fertility data obtained by various large-scale surveys have the problem of sample bias.For this reason,this thesis selects the data of family Dynamics survey from Taiwan Academic Survey research database for empirical analysis,including demographic characteristics,education,employment,marital status,spouse information,parents/spouse parents information,children’s information,living arrangements,family decision-making and expenditure data.In this thesis,from the perspective of survival analysis,the second-child birth interval was taken as a response variable,and other potential influencing factors were taken as covariables.Stata software was used to perform Kaplan-Meier product limit estimation and Log-rank test,and a multi-factor Cox proportional regression model of birth interval was established.It was found that the interval between the second child’s birth in families with one child is about 4.1 years,and the interval between the second child’s birth in 53% families is more than 3 years.From the perspective of the gender of one child,the mean interval between the second child births of families with one child being a boy is 0.7 years longer than that of families with one child being a girl,and the probability of the latter is 1.2 times higher than that of the former.The results suggest that families in which the first child is a girl are more likely to have a second child sooner.In addition,the research results also show that factors such as the later the birth year of a child,the less parents approve of the marriage,the lower education level of the interviewees and the lower income will slow down the speed of the family to have a second child,that is to say,the time interval of having a second child will be prolonged.In general,this thesis focuses on the potential factors affecting birth spacing and excavates the mechanism between family indicators and birth spacing,which is not only conducive to quantitative exploration of the law of birth behavior,but also expected to provide data reference for improving fertility rate in terms of birth spacing.