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.     

新的产业革命

微电子工业方面的非凡进展触发了一场"第二次产业革命".在这场革命中,新技术将使原来由人力操作的工种自动化.这种自动化看来会提高生产率,但将威胁大量的就业机会.当国家科学院的一个委员会声称,"现代的电子工业已经宣告了一场第二次的产业革命……它对社会的影响甚至比原来的产业革命更大",这时候就该引起我们迫切重视了.因为科学院的各个委员会向来是不夸大事实的.并不是唯独科学院指出了电子工业技术的最新进展是势不可挡的社会变革的先驱.在过     

当代意大利经济学流派评介

当今,经济学家是十分走红的人物,有人甚至称他们为"当代皇室的智囊".近几年来,经济学家充斥宣传机构、各级政府和议会.在各个领域内,经济学家们都在进行着激烈的斗争.甚至两伊战争也不是将军们的意见,而是经济学家们对关闭霍尔木兹海峡所造成的后果的预测占了压倒的地位.他们似乎扮演了这场战争的主要角色.但是,如果我们注意观察一下世界经济的发展情况就会发现:经济学家们当前在经济问题面前却是一筹莫展.在如何使经济重新繁荣起来这个问题面前,市场经济的调节者们从来没有象今天这样显得无能."新经济主义者"们则表现得更加"本分",他们主张"让市场自己     

当代世界的异化

今天大量的技术力量集中在资本主义国家,增殖资本的动力促使资本主义国家给技术发展规定了明确的方向,即把它纳入剥削劳动和剥削"无产者"国家的总实践里.因此分析技术世界的异化,应首先考虑资本必然带来的不平等和不合理.由于与资本的存在相联系的现象在阶级关系和民族关系中很重要,因而要消灭某些异化形式,就必须准备进行深刻的改革,实现社会对财富的控制.但是,某些畸变的根源应该到资本以外更深的地方去寻找.当马克思研究价值的生产和积累过程中的资本运动时,资本主义生产体系还处于尚未发展成熟的初级阶段,因此不论是对价值的生产和占有的分析,还是对由此产生的异化现象的分析,都     

Family limitation among the Old Order Amish

Summary This paper shows that the Indiana Amish, a high-fertility Anabaptist population, regulate their marital fertility according to their family finances. We linked demographic data from the Indiana Amish Directory with personal property tax records at 5, 15 and 25 years after marriage and found fertility differences by occupation and wealth. Correlations between family size and wealth at the beginning, middle and end of childbearing years were positive. Wealthier women exhibited higher marital fertility, had longer first birth intervals, were older at the birth of their last child, and had larger families than poorer women. Over the past 30 years, marital fertility has remained constant among older women; but birth rates among younger women have been rising rapidly.     

More people - more energy: it seems obvious enough,but Carter plan ignores population

In President Carter's National Energy Plan, there are variable factors, including the coal production rate, standards for home insulation and auto mileage, various taxes, but not the population growth rate. The latter factor is considered to be beyond the influence of public policy; it is a constant. This seems irrational to zero population growth proponents, for there are alternatives to continued U.S. population growth, and these alternatives are more readily attainable than some of the elements in Carter's plan. With some national initiatives in population planning, energy use would be considerably less. Thus, the question remains - Why would Carter not deal with the population factor? 1 reason for this is the fact that population planning is a long-term approach; the results are indirect and not reflected immediately in energy comsumption. Yet, a start must be made in the short-term if there are ever to be long-term benefits. Russell Peterson has suggested that Carter could be ignoring the population factor because of "political sensitivity." Carter's people have ignored the population issue, and press coverage following Carter's energy pronouncements has excluded the population factor. In a situation such as this there seems little hope for increased public awareness of the population factor in energy or other public concerns.     

Statistical materials: the family in the USSR

Statistical data are presented on the family in the USSR. Data from the 1979 census are included on number of families and their distribution by size; distribution of families by size and type, social class, and nationality; number of families including members of different nationalities, 1959-1979; number of marriages and divorces, 1960-1981; changes in age at marriage, 1960-1981; and distribution of births by age of mother, 1969-1970, 1974-1975, and 1980-1981.     

Geographic distance,the measurement of socioeconomic development,and the extent of migration

A study of migration in the region of Wojewodztwo Wloclawskie, Poland, is presented for the period 1975-1979 using a gravitational model. The model includes migration variables and variables measuring the level of socioeconomic development.     

The meaning of patient satisfaction with prepaid primary health care in Israel

This paper reports the development of a self-administered Hebrew-language questionnaire for assessing patient satisfaction with primary care in Israel. Four scale measures of patient satisfaction were empirically constructed. These scales pertained to doctor conduct, doctor-patient communication, teamwork, and ease of access. In addition, a single direct question was used to measure overall satisfaction with the care. Ratings of all aspects of care were negatively skewed, with doctor-conduct and doctor-patient communication usually being the most satisfactory aspects and access the least satisfactory. It was shown that different practices, or the same practice at different points in time, can easily and meaningfully be compared, using mean satisfaction scores, measures of standard deviation, or percentages in each practice with ratings above (or below) the overall mean of all practices. The use of specific measures of patient satisfaction for comparison and intervention is discussed.     

Blacks, whites, and attitudes towards abortion

This article examines patterns of black and white support forabortion from 1972 to 1980. The findings reveal that black-whitedifferences are present on the abortion issue. Many of the differencesare due to the different demographic characteristics of blacksand whites and the greater degree of religiosity of blacks.