Combining estimators from variety trials that are connected by control varieties only

At one site and year often numerous variety trials are performed. Sometimes these trials only have a small number of control varieties in common. It is possible to obtain best linear unbiased estimators (BLUEs) of estimable linear combinations of the variety parameters without analysing the joint observations of all trials as a whole. The unbiased local estimator of the contrast between the parameter of a new variety and the average of the parameters of the control varieties, calculated at a single trial, can be improved to the BLUE with information from the other trials. This improvement represents a contrast of contrasts between control variety parameters at the various trials. In some situations the local estimator is already the BLUE, e.g. if only one control variety is used or in case of variance-balanced designs.     

Management in the eighties: How is the job changing?

The subject of the manager in the eighties has challenged the ingenuity of quite a few management scientists and futurists. invited by the Netherlands Management Association NIVE and the Society for Strategic Planning VSB, a Dutch team of top managers from industry, banking, service companies and wholesale companies assembled 2 years ago to study the subject with the assistance of their environmental forecasters. As their analysis is based on three different societal developments, described in scenarios, their findings are internationally applicable whilst providing some stimulating food for thought.     

Real versus Nominal Convergence: National Labour Markets and the European Integration Process

ABSTRACT: This paper investigates the role of national labour market characteristics for the chances of successful transition to EMU in Europe as well as for its viability The conclusions are rather pessimistic Although overlooked by the Maastricht Treaty the need for real convergence (I e convergence of real macroeconomic variables like unemployment) is emphasized as a major condition for success However current labour market characteristics in the EC make it quite unlikely that this condition will be fulfilled We show that the implementation of the Maastricht programme might turn into an obstacle to monetary unification     

Positive-definite modification of a covariance matrix by minimizing the matrix $$\ell_{\infty}$$ ℓ ∞ norm with applications to portfolio optimization

AStA Advances in Statistical Analysis - The covariance matrix, which should be estimated from the data, plays an important role in many multivariate procedures, and its positive definiteness...     

Teamwork among midwives during neonatal resuscitation at a maternity hospital in Nepal

Problem

The ability of health care providers to work together is essential for favourable outcomes in neonatal resuscitation, but perceptions of such teamwork have rarely been studied in low-income settings.

Unemployment and Monetary Integration: On the relevance of wage-formation characteristics in a target-zone regime versus an irrevocably fixed exchange-rate regime

Abstract. This paper examines the relevance of wage-formation characteristics for the evolution of unemployment, comparing the current semi-fixed exchange rate system (EMS, described by a target zone regime) with an irrevocably fixed exchange-rate regime (EMU). The topic is analyzed in a model which emphasizes the working of the labour market and distinguishes between three types of shocks (a shock to money demand, goods demand and goods supply). The analysis points out that the impact of wage formation on unemployment depends crucially on the kind of shock as well as the exchange-rate regime in force.