The mg-procedure in ranked set sampling

The MG-procedure in ranked set sampling is studied in this paper. It is shown that the MG-procedure with any selective probability matrix provides a more efficient estimator than the sample mean based on simple random sampling. The optimum selective probability matrix in the procedure is obtained and the estimator based on it is shown to be more efficient than that studied by Yanagawa and Shirahata [5]. The median-mean estimator, which is more efficient and could be easier to apply than that proposed by McIntyre [2] and Takahashi and Wakinoto [3], is proposed when the underlying distribution function belongs to a certain subfamily of symmetric distribution functions which includes the normal, logistic and double exponential distributions among others.     

On aliasing and generalized defining relationships of factorial arrangements

The concepts of defining contrast (DC), generalized defining relationship (GDR) and aliasing structure (AS) are now well established in the terminology of regression analysis and factorial design theory. There is no complete agreement in the literature about the meaning of regular and irregular fractional factorial designs. This paper provides a workable definition of a regular fraction from a symmetrial prime-powered factorial. It characterizes the uniqueness of the GDR for fractions from the most general factorial. Results are also présentés on the uniqueness of the GDR for regular designs, on orthogonality aspects of regular and irregular designs, and on group-theoretic generation of the complete aliasing structure. Examples are provided to illustrate the developments.     

Extending Product Method of Estimation to Positive Correlation Case in Surveys

The product method of estimation (Murthy, 1964) complements the ratio method when the study variate, y, and an auxiliary variate, x, have negative correlation. However, such cases are not frequent in survey practice. This paper suggests a simple transformation of x in the more common situation of positive correlation between y and x, to permit a product method of estimation rather than a ratio method. This leads to the advantage that the bias and mean square error have exact expressions. The technique developed by Quenouille (1956) and applied by Shukla (1976) is used for making the estimator unbiased. The minimum variance situation is investigated. Two numerical examples are included. The case of negative correlation is also examined.     

Union use of employee pension funds: Introduction and overview

Summary and Conclusions A case can be made that labor unions are seeking to gain control of the financial leverage of employee pension funds as a means of offsetting a secular decline in membership which has occurred over the past twenty years and which has been accelerating. Pension fund assets are now substantial and are growing very rapidly so that even partial or indirect influence over investment policies could have major impacts on the economy. Unions have already achieved success on a limited scale with the pension fund weapon. Their intention to achieve widespread influence through this vehicle is signalled by the establishment in January, 1981, of a monthly newsletter,Labor & Investments which is devoted exclusively to the union use of employee pension funds. In sum, it is clear that the union use of employee pension funds is a very timely and significant topic. The papers that follow may not provide definitive answers to the many questions produced by this new initiative, but they do enhance our understanding of the issues involved.     

The Origins of Divergent Methodological Stances in Symbolic Interactionism*

Utilizing replies from a selected sample of contributors to the literature of symbolic interactionism, this paper examines the nature and extent of institutional ties among respondents holding similar views as to appropriate methodology in sociology. The specific institutional ties examined are those as: (1) fellow graduate students, (2) teachers and students, and (3) departmental colleagues. The methodological differences between the Chicago and Iowa schools, described in other studies, manifest themselves in the present sample, as do other views not neatly classifiable within either of these schools of symbolic interactionism. The more unconventional the conception of methodology held by a respondent, the more likely is the respondent to have been a fellow graduate student, a departmental colleague, and/or involved in a teacher-student relationship with other symbolic interactionists favoring the same conception. Respondents preferring the more orthodox methodological stances in modern sociology are less likely to have shared in such institutional ties.     

Immigration and ageing

Journal of Population Research - Contrary to popular belief, the low rates of institutionalisation of the ethnic minority aged cannot be explained by a greater availability of family support for...     

Comparison of basic data for the National Survey of Residential Group Care Facilities: 1966-1982

Major findings from this analysis of the data gathered in preparation for the 1966 and 1981 surveys of children's residential group care facilities are as follows below. In the field of residential care of pregnant adolescents, it appears that, despite an increase in the number of births to adolescent mothers since 1966, the preferred mode of serving this population is no longer residential group care. While there has been a small increase (6 facilities) in the number of residential facilities for pregnant adolescents that operate under public auspices, the 49% decrease in facilities under private auspices is the real indicator of the direction of residential services to pregnant adolescents since 1965. In the Child Welfare Stream, the most notable change between 1965 and 1981 was the decrease in the relative proportion of residential group care facilities for dependent, neglected, or abused children and youth. Overall, child welfare facilities accounted for 55% of all residential facilities listed for survey in 1965; in 1981 this percentage had fallen to 37%. As in 1965 the Child Welfare Stream was dominated by the private sector in 1981, with 83% of all child welfare facilities operating under private auspices. This pattern was found for most of the 50 individual states as well. In the Juvenile Justice Stream, the overall increase of 154% in the number of residential facilities since the 1965 listing is due in part to a notable increase in the number of private facilities in this stream of care. Although the majority of juvenile justice facilities are still public, there has been an increase of 17% since 1965 in the proportion of facilities under private auspices. An even greater increase in total number of facilities than was seen in the Juvenile Justice Stream is seen in the mental health field between 1965 and 1981. There were almost four times as many residential mental health facilities listed for survey in 1981 as in 1965. From representing about one-eighth of the total number of all residential group care facilities for children and youth with special problems or needs, the Mental Health Stream increased to a quarter of all such facilities by 1981. As in the earlier study, the Mental Health Stream was dominated by the private sector in 1981. The proportion of mental health facilities under private auspices had increased by 16% since 1965, indicating an even greater involvement of the private sector in the delivery of residential mental health services to children and youth.(ABSTRACT TRUNCATED AT 400 WORDS)     

Automatic starting point selection for function optimization

Traditional (non-stochastic) iterative methods for optimizing functions with multiple optima require a good procedure for selecting starting points. This paper illustrates how the selection of starting points can be made automatically by using a method based upon simulated annealing. We present a hybrid algorithm, possessing the accuracy of traditional routines, whilst incorporating the reliability of annealing methods, and illustrate its performance for a particularly complex practical problem.Now at the Statistical Laboratory, University of Cambridge, 16 Mill Lane, Cambridge, CB2 1SB, UK.