经济发展水平、生育政策与生育率

近年来我国人口的增长速度放缓，出生人口日益下降，出生率也到达一个很低的水平，劳动力丰富的优势渐渐消失，我国未来的发展面临着严峻考验。文章基于2005—2021年我国31个省份的面板数据，利用双向固定效应模型、工具变量法、交互效应、中介效应等方法，实证分析了经济发展水平对生育率的影响。研究结果表明：经济发展水平对生育率的提升发挥着促进作用，并且这种促进作用在不同经济发展程度的地区之间存在异质性，中部地区的经济发展水平对生育率的促进作用强于东部地区和西部地区。国家的鼓励性生育政策，如“单独二孩“”全面二孩”政策，并没有达到预期的促进生育的效果，只能减缓生育率的下降速度，并不能使生育率上升。人均消费支出在经济发展水平和生育率的关系中具有显著的反向调节作用，即人均消费支出会抑制经济发展水平对生育率的促进作用。工业化水平在经济发展水平对生育率的影响中存在部分中介效应。     

从“五普”资料看稳定低生育率政策的必要性与可行性

目前中国人口已进入低生育率阶段,对于未来的人口生育政策,形成了两种截然不同的意见:一种是继续维持较低的生育率水平,使总人口数在最短的时间内达到最高峰并转为缓慢下降;另一种是应当适时进行人口政策调整,逐渐放开二胎生育的政策,使生育率缓慢回升至一定水平再加以稳定。笔者通过对泰安市第五次人口普查的资料分析认为:稳定目前的低生育水平、严格执行现行政策仍然是当前计划生育工作的重点,我们决不能因为目前出生率处于低水平而对人口形势产生错误估计。     

基于GM(1,1)模型的我国人口发展趋势分析

计划生育政策一直广受关注,“单独二孩”政策遇冷到今年刚实施的“全面二孩”新政策更是引发了热烈讨论.新政策的实施势必影响人口的数量和结构的变化,从而影响我国经济社会的发展.文章首先分析了“全面二孩”生育政策对人口的数量、结构等方面的影响,然后通过建立灰色GM(1,1)模型预测中国未来人口发展趋势.通过研究分析发现:新政策的实行能够提高总和生育率水平、抑制出生性别比例失衡、延缓人口老龄化的进程、改善受教育程度等多种问题,而且计划生育新政策对我国未来人口数量增长具有显著促进效果,并对我国现阶段的人口问题的解决具有良好作用.     

人口发展方程模型在我国人口预测中的应用

文章以题中的统计数据为基础，考虑到今后的人口政策的调整和社会经济条件的变化等因素，利用动态的人口预测方法对我国人口增长的中短期和长期趋势进行了预测，将总和生育率（TFR）直接纳入预测模型，并考虑了生育模式对生育水平的影响，对在预测变量特别是生育率函数的取法和死亡率函数的设置上进行了讨论和改进，还在总和生育率（TFR）上进行了高、中、低水平的不同情形下进行预测，其结果是有价值的，在计划生育政策的制定上具有很好的指导意义。     

育龄人群三孩生育意愿的影响因素分析

提升育龄人群生育意愿,对促进区域可持续发展具有重要意义。文章选取西北地区育龄人群作为调查对象,运用因子分析法和结构方程模型,对影响西北地区育龄人群生育意愿的因素进行分析。结果显示：被调查者中愿意生育三孩的占18.8%,不愿意的占81.2%。在影响育龄人群生育意愿的因素中,“个体特征”显著正向影响三孩生育意愿;“家庭支持”显著正向影响三孩生育意愿;“社会福利”没有通过显著性检验,对三孩生育意愿没有显著影响;“经济因素”是影响生育意愿的关键,显著负向影响三孩生育意愿;“行为态度”显著正向影响三孩生育意愿,且往往还不受其他因素的制约。     

经济新常态、“全面二孩”政策与生育率波动——基于真实经济周期的分析测度

通过构建一个包含生育率的真实经济周期(RBC)模型,探讨中国经济新常态背景下,"全面二孩"政策放开后生育率的波动状况。研究表明:(1)包含生育率的RBC模型,对生育率的顺周期性和反周期性都具有解释能力,育儿的消费成本系数较高时,生育率呈现顺周期性特征,反之亦然。(2)考虑到中国经济新常态的历史背景,生育率的反周期特征意味着生育政策调整后生育率会有所提高,尤其在政策实施的最初几年会有明显释放;生育率的顺周期特征意味着生育政策调整后生育率在整体上不会提高,反而会继续其下滑趋势。(3)"全面二孩"政策对育儿的消费成本形成向下的冲击,能够影响中国生育率的周期性波动,但效果并不显著。从长期看,生育政策调整后总体的生育率水平不会明显改变。     

全面二孩政策对中国劳动力供求关系的影响

构建劳动力供求关系模型并对相关参数校对与说明,研究了2018—2050年全面二孩政策对中国劳动力供求关系的影响。结果表明:在假定的高速、中速和低速GDP增长条件下,全面二孩政策都能够显著改善中国劳动力供求关系。以生育政策不变时为基准,当二孩生育比例处于10%～30%较低水平时,相对于生育政策不变时缓解劳动力供求关系的效果约1.055～1.188倍;当二孩生育比例处于50%～70%中度水平时,缓解劳动力供求关系的效果约1.344～1.584倍;当二孩生育比例处于90%～100%高水平时,缓解劳动力供求关系的效果约1.856～2.112倍。无论在高速、中速和低速GDP增长假定下,各二孩生育比例指标设计下对应的劳动力供求关系整体上均呈现下降的趋势,各指标在2022年出现劳动力短缺后,至2050年整体上呈现劳动力短缺加重的趋势。这表明,在2018—2050年仅仅依靠全面二孩政策无法扭转中国劳动力短缺加重的局面。在保障二孩生育比例的同时,如何寻求全面二孩政策之外的方法来扭转中国劳动力短缺加重的局面,应成为后续的研究重点。     

通径分析与中国人口控制

本文运用通径分析方法探讨制约中国人口的中间变量和自变量,为寻找世界人口最佳控制途径提供定量分析方法和信息。制约人口数量的三个因素是:出生,死亡和迁移,其中最令人关注的是出生。它是人口再生产中最重要的人口现象。影响人口生育水平的因素是众多的,其中有对生育率起直接作用的生育意愿、生殖能力、计划生育的决策和方法等因素,它们是生育率的中间变量(即直接因素);有对生育率起间接作用的国民经济、文教卫生、社会保障等因素,它们是生育率的自变量(即间接因素)。现分别探讨如下:     

单独二孩政策对人口数量及老龄化的影响研究

文章研究“单独二孩”政策实施对人口的数量和老龄化的影响.人口政策的改变主要影响总和生育率,通过建立Leslie矩阵人口结构模型,预测我国未来不同年份各年龄人口数量.得出实施“单独二孩”政策后所增加的生育量,2015-2017年平均每年为192万,2018-2040年平均每年为29.2万,2041-2050年平均每年为48.69万人,人口在2022年达到人口峰值13.844亿人.“单独二孩”政策的实施基本不会改变我国老龄化趋势,但却能缓解我国老龄化问题.     

生育率结构性变化与新生人口激增——基于北京的APC模型实证研究

在全国新生人口不断减少的背景下,北京新生人口在2005-2010年却出现了跳跃式增长,常住人口数量、育龄妇女规模和总和生育率的变化均不能有效解释这一现象.本文采用分年龄结构的育龄妇女生育动态数据,基于APC模型对新生人口激增背后的生育率结构性变化进行了研究.研究发现,育龄妇女生育高峰年龄滞后、高龄妇女生育率提高使得生育率发生结构性变化,是北京新生人口激增的根本原因.APC模型估计结果显示,1970年前后出生的育龄妇女生育意愿最高,并处于生理生育高峰,对新生人口增长贡献最大.     

Determinants of Contraceptive Use in Egypt: A Multilevel Approach

The increasing use of family planning methods seems to be the intermediate determinant which mostly influences the fertility decline in developing countries, and in particular in those countries which are in an advanced phase of demographic transition such as Egypt. Moreover large countries, like Egypt, are characterized by very different geographical realities and even by strong regional heterogeneities. The aim of this study is the analysis of the determinants of contraceptive use in Egypt, with particular reference to the differentials due to the socio-economic context and to the area of residence. To estimate each individual and regional factors’ effect on contraceptive use, a logistic two-level random intercept model is fitted to EDHS 2000 data; the use of a multilevel analysis is suggested by the two-level data structure: the first level units are the women, the second level units are their regions of residence.     

Seasonal patterns of fertility measures: theory and data

The distribution of births by month exhibits a seasonal pattern in most populations. The monthly marital fertility rate for an area of Bangladesh provides a good example of the seasonal periodicity. Seasonal patterns of measures of reproduction in a population of married women are considered. Equations are developed that predict the seasonal patterns of these alternative measures under the assumption that the fertility rate (R) follows a trigonometric curve. This is followed by an empirical analysis of the measures in a Bangladesh population that has a pronounced seasonal fertility. The investigation is intended both to validate the theoretical framework developed in the 1st part of the paper as well as to determine whether seasonal variation in actual populations is sufficiently large to affect the alternative measures significantly. 4 measures are considered: pregnancy prevalence (PP)--the proportion of married women who are pregnant at the survey date; mean open birth interval (MOI)--the time from the last live birth to the date of the survey for parous women and from the time of marriage to the date of the survey for nulliparous women; mean closed interval-birth (MCIB)--the mean interval between the last 2 live births for married women who have a birth in the period immediately preceding the survey date; and mean closed interval-woman (MCIW)--the mean interval between the last 2 live births for women who have had at least 2 children by the time of the survey. It is assumed that the seasonal pattern of the fertility rate of a population follows a cosine curve and that there is no trend in annual fertility from year to year. The lag and relative variability of the other measures are considered in comparison with the fertility rate curve. The predictions from this theoretical effort, when compared with observed patterns and trigonometric regression results for each measure in data from Bangladesh, are shown to be quite accurate. The figure and regression results show that R, PP, and MOI have definite seasonal periodicity, but MCIB and MCIW do not display any seasonal patterns. If there is a secular trend in fertility in addition to seasonality, these relationships between the seasonal patterns of the measures may no longer hold. There is a disadvantage to using closed interval measures, for they are unable to detect effects of limiting of childbearing in a population since they are based only on information from women who have births.     

Models of procreative behavior based on the concept of the life cycle

This is the first in a planned series of papers applying path analysis methods to the study of reproductive behavior in rural areas in Poland. Factors considered include total number of births, birth intervals, birth control and abortion, and future fertility intentions. The objective is to examine how the fertility of rural women is affected by various social and economic factors. (SUMMARY IN ENG)     

The Italian Labour Force Survey to estimate fertility

The own-children method (OCM) applied to the Italian Labour Force Survey (ILFS) is an alternative way to give information on fertility for the years before the survey. By deriving children information and the population at risk on the basis of parents’ characteristics, a large-scale dataset for fertility analysis in Italy becomes available, also to reconstruct event histories. The quality assessment provided by comparing the total fertility rate (TFR) calculated on ILFS with the official regional and national TFRs by ISTAT gives us usable outcomes.     

Modelling individual fertility levels in Malawian women: a spatial semiparametric regression model

We applied semiparametric spatial Poisson models to analyse fertility decisions at individual level in Malawi. We used the 2000 Malawi Demographic and Health Survey (MDHS) to investigate determinants of fertility, in the model that allowed for nonlinear, fixed and spatial risk factors. Inference was based on the Bayesian approach. The unstructured spatial effects were modelled using the exchangeable prior, while for the structured spatial effects we used the intrinsic conditional autoregressive models. Nonlinear effects were modelled using P-splines. Results showed non-linear declining trends of fertility with year of marriage and increasing trends with age at marriage. We also observed significant unstructured effects, however, no significant spatial autocorrelated effects were displayed. Overall, total spatial effects were significantly different at district level.     

Forecasting births in post-transition population: stochastic renewal with serially correlated fertility

Time series analysis of fertility can improve demographic forecasts. The optimal forecast and its variance for births to an age-structured population subject to serially correlated random fertility are developed. The general case in which the fertility process had arbitrary autoregressive structure is dealt with and then the 4 special cases of white noise, 1st-order autoregressive, 2nd-order autoregressive, and random walk are considered. Consequently, it is determined that the predictions and their variances are highly sensitive to the autoregressive structure of fertility and, therefore, if stochastic models are to be used for prediction, they must emphasize this aspect of the problem. Preliminary empirical efforts to model the time series of U.S. fertility from 1917 to 1972 proved unsuccessful, but it is obvious that at least a 2nd-order autoregressive scheme is require d. The analysis proveded should be helpful in: 1) any application of the procedures requires a successful parameterization of the fertility process; 2) fertility variations could be decomposed into the effects of nuptiality and marital fertility and then births and marriages could be jointly predicted; and 3) the simplifying approximations should be dropped and each age-specific rate could be analyzed and predicted.     

Assessing the use of sample selection models in the estimation of fertility postponement effects

Several studies have shown that at the individual level there exists a negative relationship between age at first birth and completed fertility. Using twin data in order to control for unobserved heterogeneity as possible source of bias, Kohler et al. (2001) showed the significant presence of such "postponement effect" at the micro level. In this paper, we apply sample selection models, where selection is based on having or not having had a first birth at all, to estimate the impact of postponing first births on subsequent fertility for four European nations, three of which have now lowest-low fertility levels. We use data from a set of comparative surveys (Fertility and Family Surveys), and we apply sample selection models on the logarithm of total fertility and on the progression to the second birth. Our results show that postponement effects are only very slightly affected by sample selection biases, so that sample selection models do not improve significantly the results of standard regression techniques on selected samples. Our results confirm that the postponement effect is higher in countries with lowest-low fertility levels.     

Demographic problems of military reform in the USSR

The author discusses future reforms in the procedures for drafting personnel into the Soviet army. The analysis is based primarily on the experiences of armies in Western countries. The author also takes into consideration peculiarities of the political and economic structures in the USSR, as well as the attitude of the Soviet people toward military service. The demographic situation at the end of the twentieth and the beginning of the twenty-first century is examined, as is the possibility that a decrease in fertility, worsening life expectancy, and increase in international migration could make the military draft process even more complicated. Data for cohorts born in 1972, 1977, 1982, and 1987 are used as illustrations. The possibility of developing an alternative service is suggested.     

新生代农民工家庭式迁移城市意愿影响因素研究——以西安市为例

农民工的家庭式迁移城市是真正完成农村剩余劳动力转移,推进城市化进程的必然途径,而新生代农民工作为当前农民工的新生力量正在逐渐成为农村剩余劳动力的中坚力量,其家庭式迁移城市的意愿受多方面因素的影响,而这些因素恰恰是政府制定政策以引导农民工合理流动有序转移的最根本依据.以西安地区为例,通过对西安城六区进行间卷调查,利用1 040个农民工样本数据,采用层次分析法对新生代农民工家庭式迁移城市意愿影响因素进行分析,确定各影响因素的重要性程度,发现职业收入、外出务工时间、受教育程度、社会保障制度对新生代农民工家庭迁移城市有重要影响,年龄、婚姻状况、户籍制度则影响不明显.     

中国短期利率跳跃行为的实证研究

内容提要：通过在Vasicek模型中引入跳跃强度与宏观经济变量相关的跳跃成分,本文建立了一个更具一般性的跳跃－扩散动态利率期限结构模型,并对该模型的五种不同形式进行了实证比较与分析。借助于新模型和比较结果,本文对中国短期利率的跳跃行为进行了实证研究。结果表明：（1）短期利率不仅存在均值回复和扩散行为,还存在显著的跳跃行为;（2）短期利率的跳跃强度存在显著的正向水平效应和宏观经济效应 ,但水平效应比宏观经济效应更显著;（3）跳跃行为、跳跃强度的水平效应以及宏观经济效应在刻画利率动态行为时都是必要的,现有的跳跃－扩散模型不足以描述中国短期利率的动态行为特征;（4）随着跳跃、跳跃强度的宏观经济效应和水平效应的逐步引入,模型的拟合优度和预测能力逐步显著提高。