Robustness to the unavailability of data in block designs

We present general results for finding or boundingt _maxB , the maximum number of arbitrary whole blocks of observations which can be removed from a block design, and still leave all of the elementary treatment contrasts estimable. The block sizes may be larger than the number of treatments. The results are applied to BBDs, reinforced BIBDs and BBDs, BTIBDs, and a series of variance balanced incomplete block designs with two block sizes. Also given for most of these designs, are results fort _max, the maximum number of arbitrary, scattered observations that can become unavailable, and still leave all of the elementary treatment contrasts estimable.The work was undertaken while Dr. Whittinghill was visiting Ohio State University, and supported by a grant from the Natural Sciences Division, Colby College, Waterville, Maine.     

Testing equality of variances in the analysis of repeated measurements

The problem of comparing the precisions of two instruments using repeated measurements can be cast as an extension of the Pitman-Morgan problem of testing equality of variances of a bivariate normal distribution. Hawkins (1981) decomposes the hypothesis of equal variances in this model into two subhypotheses for which simple tests exist. For the overall hypothesis he proposes to combine the tests of the subhypotheses using Fisher's method and empirically compares the component tests and their combination with the likelihood ratio test. In this paper an attempt is made to resolve some discrepancies and puzzling conclusions in Hawkins's study and to propose simple modifications.
The new tests are compared to the tests discussed by Hawkins and to each other both in terms of the finite sample power (estimated by Monte Carlo simulation) and theoretically in terms of asymptotic relative efficiencies.     

Abstracts

Quality & Quantity -     

BOOK REVIEWS AND NOTES

Book reviews in this article: G.D.H. COLE AND INDUSTRIAL DEMOCRACY: A REVIEW: The World of Labour Introduction by John Lovell G.D.H. COLE AND INDUSTRIAL DEMOCRACY: A REVIEW: Self-Government in Industry Introduction by J. G. Corina G.D.H. COLE AND INDUSTRIAL DEMOCRACY: A REVIEW: Workshop Organisation Introduction by A. I. Marsh WORKPLACE INDUSTRIAL RELATIONS: Building: Teamwork or Conflict? by L. G. Bayley The Management of Wage Payment Systems by Alan Gillespie Labour Relations on the Docks by M. Jackson ORGANIZATIONAL BEHAVIOUR: Social Psychology of the Work Organisation by A. S. Tannenbaum Organisational Problems in European Manufacture by T. D. Weinshall LABOUR ECONOMICS: Manpower Economics by E. B. Jakubaus and Neil A. Palomba Labour Economics by J. E. King Unemployment and Wage Inflation with Special Reference to Britain and the U.S.A. by J. Taylor UNEMPLOYMENT: Regional Unemployment Differences in Great Britain by P. C. Cheshire Interregional Migration Models and their Application to Great Britain by R. Weeden The Changing Pattern of Employment—Regional Specialisation and Industrial Localisation in Britain by M. Chisholm and J. Oeppen Men Out of Work—A Study of Unemployment in Three English Towns by M. J. Hill, R. M. Harrison, A. V. Sargeant and V. Talbot Do The Poor Want To Work? A Social-Psychological Study of Work Orientation by L. Goodwin Marienthal: The Sociography of an Unemployed Community by M. Jahoda, P. F. Lazarsfeld and H. Zeisel b     

Forecasting first births

This study is concerned with one aspect of the family cycle, namely, the transition from young married to young married with small children. The focus is on developing models to forecast entries into this latter stage for the purpose of marketing research. "Using ordinary least squares, forecasting models were estimated for (1) total number of first births, (2) number of white first births, and (3) number of nonwhite first births." Models are estimated for both the United States and California using data from official sources.     

The maintenance, funding and modification of retiree medical benefits

Retiree medical benefits are an ever-growing concern as costs escalate and the date for implementation of Statement of Financial Accounting Standards No. 106 approaches. These authors summarize case law relevant to employers' right to modify or terminate benefits and discuss methods of funding theses liabilities.     

Politically stable pay-as-you-go pension systems: When the social-insurance budget is too small in a democracy

The essay analyzes in an overlapping-generations model, to which extent a pay-as-you-go pension system will be the outcome of majority voting, given specific institutional set-ups. Clearly, the vote of an active person depends on his expectations about how the present decision (i.e., his contribution) is linked to the future (i.e., his benefits), when he will be retired. In the paper we employ the assumption of a basic social contract where each active voter's future benefits are positively related to his contributions. It is shown that in this framework a steady-state with a positive (though lower than optimal) level of the pension system exists, even if a new majority decision about the system takes place every period.