On the transient behaviour of the GI/G/1 waiting-times

Abstract

Consider a single-server queuing system, where the arrival intervals T_i and the service-times U_i of consecutive customers form two independent sequences of independent and equally distributed random variables. Assume that customers arriving when the server is busy line up and that they are then served in order of arrival. Let W_n be the waiting-time of the nth customer and suppose that the server is idle at the start, i.e. W₁ = 0. Put W = lim _n ∞ W_n when the limit exists. Furthermore, let F_n (?) be the c.d.f. of W_n and put EW_n =ω _n .     

Cooperatives and consumer research

The article asks the question why consumer researchers sometimes try to invent an organization to represent the consumer interest when there already is an existing organization with the required characteristics: consumer cooperatives. The advantages of having a consumer organization with its own production and distribution facilities are pointed out. The key role of consumer research to help realize the inherent possibilities of consumer cooperatives to become the main organization representing the consumer interest is stressed and some possible project ideas for research are formulated.

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Kooperative und Verbraucherforschung

Zusammenfassung Der Beitrag geht aus von der Frage, warum Verbraucherforscher manchmal versuchen, eine Organisation zur Vertretung von Verbraucherinterssen zu erfinden, obwohl es mit den Verbraucher-Kooperativen bereits eine Organisationsform gibt, die im Prinzip die geforderten Eigenschaften hat.Der Beitrag beschreibt die wesentlichen Eigenschaften von Verbraucher-Kooperativen. Grundsätzlich ist eine solche Kooperative eine Gruppe von Verbrauchern, die praktische Demokratie in der Form pflegen, daß durch ständigen Dialog bestimmt wird, was zur Befriedigung der Bedürfnisse der Mitgliedshaushalte produziert und verteilt wird. Beispiele bestehender und entstehender Kooperative zeigen, welche Möglichkeiten diese Organisationsform für die Stärkung der Verbraucherposition birgt. Erste Forschungsergebnisse lassen vermuten, daß Verbraucher-Kooperative für Verbraucherforscher ein lohnendes Forschungsobjekt sein dürften, wenn es um die Erforschung wirkungsvoller Mittel zur Stärkung der Verbraucherposition geht. Der Beitrag schlägt nicht nur Fragestellungen und Ideen für Forschungsprojekte vor, sondern diskutiert auch die normative Grundlage solcher Projekte.Ziel ist dabei die Entwicklung solcher theoretischer Ansätze, Konzepte und Aktionsforschungs-Vorhaben, die Verbrauchern dazu verhelfen, in der Organisationsform der Kooperative durch Diskussion die optimalen Wege zur Bedürfnisbefriedigung zu finden. Wenn sich Verbraucherforscher an solchen Projekten beteiligen, könnten sie zu einem Schlüsselfaktor für die Entwicklung der Verbraucher-Kooperative zu einem der wichtigsten Mittel zur Förderung des Verbraucherinteresses in der Gesellschaft werden.

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Kai Blomqvist is Programme Director at the Swedish Cooperative Institute, Box 15200, S-104 65 Stockholm, Sweden, and Main Secretary to the Government Commission for the review of public consumer policy in Sweden.     

Privatization of social care delivery – how can contracts be specified?

When contracting out services to private actors, public authorities must be able to ensure that the quality of services provided is satisfactory. Therefore, it is important to formulate precise quality requirements, thus making them possible to monitor. In the study, 1,005 quality requirements from public procurements of nursing homes were categorized, and their degree of monitorability assessed. The analysis showed that quality requirements related to ‘soft’ areas such as social activities typically were non-monitorable. The requirements were written in an imprecise, vague manner, thus making it difficult for the local governments to determine whether or not they were met.     

Finland's monetary autonomy

A time-series analysis of Japanese data for the period 1966–85 estimates the effectiveness of seat belt and government safety policies on various types of traffic-related fatalities. The results indicate that these policies reduce the risk of death for both motor vehicle occupants and non-occupants.     

Public health insurance and optimal income taxation

If individuals differ not only in their inherent capacity to earn income, but also in the probability that they will fall ill, can subsidized public health insurance be justified on the grounds that it serves as an efficient tool to redistribute welfare? This question is analyzed in a model where the social welfare function is a weighted average of individual expected utilities, and where taxation is by a linear income tax. The answer is ‘yes’, except in certain special cases.     

A note on the extended elementary renewal theorem

Abstract

Let X ₁ ^(µ), X ₂ ^(µ), ... be an infinite sequence of independent and identically distributed random variables defined on the whole real axis and with EX₁ ^(µ) = µ > 0. Put M_n ^(µ) = max (S₀ ^(µ), S₁ ^(µ), ..., S_n ^(µ) , where S_n ^(µ) = X₁ ^(µ) + ... + X_n ^(µ) for n = 1 , 2, ... and S₀ ^(µ) = 0, and define