Testing circular symmetry

The author addresses the problem of testing circular data for reflective symmetry about an unknown central direction and proposes a simple omnibus test based on the sample second sine moment about an estimation of this direction. Under quite general conditions, for an underlying distribution which is reflectively symmetric, the large‐sample asymptotic distribution of the test statistic is standard normal. Randomization and bootstrap variants of the test are also introduced, and the operating characteristics of different versions of the test are investigated in a Monte Carlo study. The large‐sample and bootstrap versions of the test are applied in the analysis of two illustrative examples drawn from the circular statistics literature.     

Range management and production on the fringe: The Caldenal, Argentina

North American problems in coming to terms with the management of the semi-arid Plains environment are well known. Less documented are those of Argentina's equivalent on the fringe of the Humid Pampas. Argentine agricultural aid and research has been focussed on the Humid Pampas, and little understanding of the special problems of the dry zone is apparent. Issues of production and conservation are in urgent need of attention. In addition to the limits posed by the natural environment, a number of human factors affect the ability of ranchers to produce from the dry lands. In a field study of the Caldenal, some indications are that the factors are different from other environments in Latin America. Large properties are not less productive per hectare than small, and standard technology does not guarantee good results from ranching. Tenant farming is not a problem, but there is an impoverished group, those ranchers without other means of earning a livelihood. A recommendation is for encouragement to be given to larger ranch units, and for more research into relevant technology, which is likely to include conservationist measures, whose introduction to the ranches should be financially supported.     

Social work and day care: a role looking for a profession

The profession's present role in day care is assessed through a review of the social work literature. This analysis suggests that the profession is not systematically involved enough in child care systems on a local or national basis. The author discusses why this is so, and suggests professional points of access for social workers interested in providing social services in different types of child care. In addition, it is recommended that more policy and programmatic emphases be put on providing social services to family day care homes, the care of children by their relatives, and for centers that serve ethnic minorities and disadvantaged families.I wish to thank Beatrice Saunders and Eleanor Brilliant for their help in writing this article.     

Allocation of research and development funds: A zero-one goal programming approach

The research and development project selection process is one of the most difficult and important problems faced by management. It is typically complicated by indivisibility of projects and multiple and conflicting objectives, in addition to limitations on funding, facilities, and qualified researchers. In this paper a case example involving a high technology electrical equipment manufacturer is developed to illustrate this problem using zero—one goal programming to accommodate indivisibility of projects in addition to multiple and conflicting goals. The model presented is an attempt to provide managers with a robust tool for allocating scarce resources among research and development projects.     

Labor force participation and family formation: A study of working mothers

Drawing upon a sample of 638 mothers aged 18 to 40, with at least some marital work experience, significant associations were found between the extent, kind, and timing of employment and a series of family formation variables. Generally lower fertility, longer first birth intervals, and earlier use of birth control were associated with the longest work durations, the highest status jobs, and work before the birth of the first child. The data failed, however, to differentiate desired family size.