Maximum likelihood estimates for the parameters of a continuous time model for first conception

The duration of time between two successive births or between marriage and first birth is an indicator of the level of fertility of a couple. Potter and Parker (1964) and Singh (1961, 1967) have suggested the Type I Geometric as a distribution appropriate for representing the length of interval to first conception leading to a live birth. Potter and Parker estimated the parameters of this distribution with the help of the first two moments. Majumdar and Sheps (1970) pointed out the limitations of these moment estimates and gave a method to obtain maximum likelihood estimates, based on formulas which are too involved for solution without the help of a computer. Singh proposed a continuous probability distribution based on another set of assumptions for the above situation. He outlined a method to obtain best asymptotically normal estimates of the parameters. These estimates are obtained after several iterations starting from any set of consistent estimates. The objective of this paper is to show that it is relatively easier to obtain maximum likelihood estimates of the parameters of the continuous model, which describes the data on duration to first conception as well as does the discrete model. Simple expressions for the moment and maximum likelihood estimates with the corresponding covariance matrices are obtained. Application is made to three sets of data.     

Assessment of family planning programme effects on births: Preliminary results obtained through direct matching of birth and programme acceptor records

Abstract In order to match birth and family planning acceptance records and thereby to obtain estimates of pre- and post-acceptance fertility, use is made of seven-digit national identity card numbers, issued to all adult West Malaysians. These unique numbers are recorded on live-birth records and national family planning programme acceptor records of West Malaysian women. The application and preliminary results of this method of direct computer matching of these sets of records for assessing the effects of a family planning programme on fertility are described. Pre- and post-acceptance fertility rates are presented in terms of contraceptive methods used, and the key characteristics of race and age of programme acceptors, and are discussed in terms of marital duration and number of children at the time of acceptance.     

A cost benefit analysis of the barbados family planning programme

Abstract Of the Caribbean islands, Barbados has the lowest fertility level. The crude birth rate in 1970 was only 20·5 per 1,000, which is one of the lowest found in any country of similar economic development anywhere in the world. In 1960 the crude birth rate was much higher, at about 33·6 and for almost 40 years before that had fluctuated around a value of 33. Thus, a decline of about 40% has been achieved within the comparatively short period of a decade. The reasons for this rapid decline are of particular interest to all those concerned with population growth and economic development in the less developed areas. In Barbados, the importance of population control and the role of family planning was recognised early by the government and other civic agencies, and the Barbados Family Planning Association (BFPA), an autonomous national family planning agency, was established. Since its modest beginning in 1955 the BFPA has grown to be a major social institution, comprising 14 clinics situated in various localities throughout the island. In 1970, a full-time staff of 28 were providing services to an estimated 10,000 clients, about 20% of all women of reproductive age. Funds for the BFPA have come from local government with considerable assistance from international agencies.     

Reproductive time lost due to sexual union dissolution in San José, Costa Rica

Abstract It has long been recognized, on a theoretical level, that widowhood, divorce, and separation, if not immediately followed by re-marriage, could have a negative impact on fertility. Davis and Blake specifically identified the amount of reproductive time spent after or between unions as one of the eleven intermediate variables bearing immediately upon fertility.     

Fertility differentials among the tribal groups of Sierra Leone

Abstract Sierra Leone is in a position typical of many African countries regarding accurate information on her basic demographic characteristics. Such vital registration as exists is confined to a small area and there has been only one census of any reliability, that of 1963. Estimates of fertility levels from the age distribution obtained from that enumeration have been made by Dow, the method having been used previously by Van de Walle for Nigeria.     

Social choice theory in the case of von Neumann-Morgenstern utilities

Part I of this paper offers a novel result in social choice theory by extending Harsanyi's well-known utilitarian theorem into a multi-profile context. Harsanyi was contented with showing that if the individuals' utilities u _i are von Neumann-Morgenstern, and if the given utility u of the social planner is VNM as well, then the Pareto indifference rule implies that u is affine in terms of the u _i. We provide a related conclusion by considering u as functionally dependent on the u _i, through a suitably restricted social welfare functional (u ₁,...,u _n)u=f(u ₁,...,u _n). We claim that this result is more in accordance with contemporary social choice theory than Harsanyi's single-profile theorem is. Besides, harsanyi's initial proof of the latter was faulty. Part II of this paper offers an alternative argument which is intended to be both general and simple enough, contrary to the recent proofs published by Fishburn and others. It finally investigates the affine independence problem on the u _i discussed by Fishburn as a corollary to harsanyi's theorem.The authors are indebted to L. Haddad, A. Sen and two anonymous referees for useful written comments. They also benefited from stimulating remarks in seminars and helpful conversations with their colleagues. The usual caveat of course applies. One of the authors acknowledges partial financial support from the ARI Communication of the C.N.R.S., Paris.     

A quantitative theory of preferences: Some results on transition functions

We investigate a general theory of combining individual preferences into collective choice. The preferences are treated quantitatively, by means of preference functions (a,b), where 0(a,b) expresses the degree of preference of a to b. A transition function is a function (x,y) which computes (a,c) from (a,b) and (b,c), namely (a,c)=((a,b),(b,c)). We prove that given certain (reasonable) conditions on how individual preferences are aggregated, there is only one transition function that satisfies these conditions, namely the function (x,y)=x·y (multiplication of odds). We also formulate a property of transition functions called invariance, and prove that there is no invariant transition function; this impossibility theorem shows limitations of the quantitative method.Research supported in part by the National Science Foundation.     

UNIONS, PLANTS, JOBS, AND WORKERS

The relationship between unions and their members is an important, yet neglected, subject in recent studies of the sociology of work. This study develops and tests a theory of union satisfaction and participation that combines recent research in the sociology of work with previous explanations of union satisfaction and participation provided by industrial relations researchers, in an attempt to understand the relationship between unions, plants, jobs, and workers in U.S. manufacturing industries. This theory predicts that union members will be satisfied with their unions and participate more in them if there are extensive ties between workers, employers, and unions. These ties stem from the focus of labor/management relations in particular, and class struggles in general, on market outcomes and the historical linkage of union membership with employment in the United States. The theory also predicts that unions them-selves act as ties to specific work settings and that union participation is a forum for voicing dissatisfaction with specific characteristics of workers' jobs. Testing these predictions is complicated by contradictory nature of the structure and organization of work in advanced industrial societies. The analysis provides qualified support for this theory, with data drawn from more unions, plants, and union members than have been used to date. In addition to discussing modifications to the theory and analysis presented here, the study includes a discussion of its implications for the future of unionization and the organization of work, in light of declines in union membership, increased efforts to decertify unions and resist union organizing efforts, and deindustrialization in the United States.     

Migration and development: myths and reality

Recent research on the impact of labor migration on the socioeconomic development of developing countries has provided opportunity to try and resolve some of the long-standing polemics that have pervaded the literature on migration and development. This article focuses on findings concerning the labor, remittance, and social impacts of emigration on countries that have participated in labor emigration. While a great deal more research needs to be done, recent findings confirm that in some situations the sort-term impacts of labor migration on sending countries have been considerable.