The historical decline of fertility in Eastern Europe

I test the hypothesis that the growth of autonomy was the factor responsible for the decline of marital fertility in eight Eastern European countries. By growth of autonomy I mean increased control over one's political, personal, religious, economic and reproductive life. This increased control was manifested in revolutions, democratic political reforms, nationalist movements and declining marital fertility. The political reforms were the result of the growth of autonomy but they also accelerated the dissemination of these new ideas among the populace contributing to further growth of autonomy. My hypothesis is generally supported by the historical data.     

A hypothesis about the decline of fertility

The hypothesis proposed earlier seems to be supported by the analysis of U.S. fertility. Urbanization was consistently negatively correlated with thelevel of fertility in 1810, 1860, 1920, and 1940. Urbanization was not significantly correlated with thedecline of fertility in the period, i.e. from 1800 to 1860; from 1860 to 1920; and from 1920 to 1940. For the period from 1800 to 1860, however, the decline was closely associated with a proxy variable for what is called the spirit of autonomy, i.e., a feeling of control over one's life. It is hypothesized that this sense of control extended to control over fertility. After 1860 the ideas became so widespread that they were no longer associated with any particular group, region, religion, or class. It was just a matter of time until the ideas spread slowly to all groups.     

Business games and implementation research

This paper reviews some recent research in OR implementation and suggests that a new approach is required, which will take fuller account of the perceptions of managers concerned with the problem. Research games in business settings seem to offer a means for such approach. Some lessons learned from a business game used in this way are described and their implications for modelbuilders are discussed.     

Experience with a multi-year fleet planning model

The fleet planning problem requires determination of the changing airline fleet mix based on existing traffic levels and projected growth, on the existing fleet, various aircraft types available in the future, and other operational and financial considerations. Several applicable mathematical formulations have been reported. One of these has been programmed for the computer and used by the authors for several years. This paper discusses the application of that model to real airline planning situations. Such practical experience has effected changes in the program and the manner it is used in fleet planning studies.     

Hard and soft constraints in linear programming

The linear programme and its constraints are split into two parts. The first consists of the traditional structure, the second being akin to goal programming. SOFT constraints are weighted relative to each other and then approximately weighted relative to the HARD constraints. The LP is run four times giving different emphasis to the SOFT and HARD constraints. The manager requesting the LP has then to decide which gives the most appropriate solution.     

Economic lot disposition policies for single attribute sampling plans

Traditionally, single sampling plans have provided but two possible lot disposition policies, either to (1) accept or reject and screen, or to (2) accept or reject and scrap. This is particularly true of statistical designs. Economically based plans, however, provide a framework wherein several lot disposition policies may be invoked in accordance with estimated lot quality. This paper illustrates how such designs may be realized.