Einige Bemerkungen zur statistischen Messung der Konzentration

Zusammenfassung Nach einer kritischen Analyse der Begriffe „absolute“ und „relative“ Konzentration werden einige Kriterien gegeben, die Ma?zahlen der absoluten oder der relativen Konzentration zu erfüllen haben. Hierauf wird untersucht, inwieweit die gebr?uchlichsten Ma?zahlen der Konzentration (Gini, Herfindahl, Münzner) diese Kriterien erfüllen. Dann wird gezeigt, da? sich eine vonAdam angegebene, sehr allgemeine Klasse von Ma?zahlen als Ma?zahlen der absoluten Konzentration qualifizieren; einige wichtige Spezialf?lle werden genauer untersucht. Im vorletzten Teil der Arbeit werden Ma?zahlen für die Ver?nderung der Konzentration diskutiert und schlie?lich an einem praktischen Beispiel erprobt.

---

Summary After analysing the concepts of “absolute concentration” versus “relative concentration”, some criteria for coefficients of concentration are given to qualify them either as measures for absolute or for relative concentration. On the basis of these criteria, some well-known coefficients (Gini, Herfindahl, Münzner) are examined. Furthermore, it is shown that the measures of “predictivity” as given byAdam can be regarded as coefficients of absolute concentration; some important special cases (one of which the Herfindahl index) are investigated. Finally, measures for the change in concentration are developed and applied to a practical example.

     

Ein verallgemeinerter Geburten- und Todesprozeß zur Erklärung der Entwicklung des deutschen Volkseinkommens, 1851–1939

Ohne Zusammenfassung     

HOW IDEOLOGIES SUPPLANT FORMAL STRUCTURES AND SHAPE RESPONSES TO ENVIRONMENTS

Observations of nineteen hospitals show how organizational ideologies are manifested and sustained by beliefs, stories, languages, and ceremonial acts. The data indicate that harmonious ideologies accompany simple structures, but that discordant ones accompany elaborate structures. Through their effects on people and structures, ideologies guide organizations’responses to external threats.     

The occurrence of outliers in the explanatory variable considered in an errors-in-variables framework

Summary The problem of estimating the slope of a linear relationship between two jointly normally distributed random variables is considered when outliers may occur in the explanatory variable. It will be studied as a special case of an errors-in-variables problem where the explanatory variable is measured which a nonnormally distributed error. In this more general model and under certain conditions a consistent estimator can be given with a normal limiting distribution. Applications to cases of outliers in the explanatory variable will be presented.     

A model of the Dutch labour market (AMO-K)

Summary So far, the labour market has not received any special attention from macro-econometric model builders. In this article an attempt has been made to describe the labour market in detail, paying attention to such important phenomena as the friction between labour supply and demand, the heterogeneity of labour, the dependence of labour supply on the labour-market situation, the Phillips mechanism and the impact of real wages on labour demand. To make it suitable for policy simulations, the model has been extended to a complete macro-econometric model, taking account of the fact that both labour and capital limit the production possibilities.This paper summarises an extensive Dutch report on the construction of a model for the Netherlands labour market. The title of the original report is AMO-K: Een arbeidsmarktmodel met twee categorieën arbeid; (AMO-K, A labour-market model with two categories of labour) ; it was published by the Netherlands Economic Institute (NEI) in Rotterdam in the so-called Olive Series, 1982-2, pp. 403ff. Some details of the model presented in that report were changed after its publication; see G. den Broeder, AMO-K 81-12, Tussenrapport betreffende de verdere ontwikkeling van het arbeidsmarktmodel (Interim report on the further development of the labourmarket model), Rotterdam, September 1983. Since then, only minor changes have been carried through. The model reproduced in this paper is the modified version. The model was developed within the National Programme of Labour-Market Research (NPAO) (now defunct), the NPAO organisation having granted a commission to the NEI in Rotterdam.     

Characteristics of agricultural input package users in communal clubs serviced by Acat in KwaZulu: A note

Characteristics of communal club members who use input packages are studied using a survey of communal clubs serviced by Africa Co‐operative Action Trust (Acat) in KwaZulu during 1989. Discriminant analysis shows that full input package adopters tend to belong to older clubs, have less formal savings and receive more visits each year from KwaZulu Department of Agriculture (KDA) extension officers. They also have a greater proportion of land under sugar‐cane, larger farm sizes and a higher rand monetary value of livestock.

Members of older clubs benefit from greater club experience in ordering inputs and liquidity for securing discounts on bulk orders. Clubs also enable scarce KDA extension manpower resources to be used more effectively by focusing extension efforts on groups rather than individual farmers. Sugar‐cane production probably indicates member willingness to innovate and the availability of funds to buy complete input packages for other crops. Increased access to land promotes input package adoption which can raise agricultural productivity. Development of institutional arrangements for a land rental market in KwaZulu should be considered. Higher monetary values of livestock reflect Increased ability to bear risk associated with technology adoption and that adopters have the means to purchase input packages