through the Economic Research Initiative on the Uninsured. We are grateful to Peter Diamond and Jon Gruber for helpful conversations, to Didem Bernard for advice regarding data and to Charlie Brown, Randy Ellis, Albert Ma, Tom McGuire and participants at the ERIU Conference for helpful comments. We are solely responsible for the views We develop a model in which firms hire heterogeneous workers but must offer all workers insurance benefits under similar terms. In equilibrium, some firms offer free health insurance, some require an employee premium payment and some do not offer insurance. Making the employee contribution pre-tax lowers the cost to workers of a given employee premium and encourages more firms to charge. This increases the offer rate, lowers the take-up rate, increases (decreases) coverage among high (low) demand groups, with an indeterminate overall effect. We test the model using the expansion of section 125 plans Between 1986 and 1997 the use of section 125 plans, which allow employee contributions to insurance premiums to be paid on a pre-tax basis, grew rapidly. Yet over roughly the

address:

Entry in liberalized railway markets: The German experience Contact Author

Procedure summaries are an approximation of the effect of a procedure call. They have been used to prove partial correctness and safety properties. In this paper, we introduce a generalized notion of procedure summaries and present a frame-work to verify total correctness and liveness properties of a general class of while programs with recursion. We provide a fixpoint system for computing summaries, and a proof rule for total correctness of a program given a summary. With suit-able abstraction methods and algorithms for efficient summary computation, the results presented here can be used for the automatic verification of termination and liveness properties for while programs with recursion.

societal levels. One potential user for a DSS operating at trans-boundary level is the Volta Basin Authority, created in 2006 by the

This report has long been awaitedprimarily by us the authors but also by a number of colleagues who kept asking for it We had hoped to complete it earlier but several factors caused the nal preparation to take longer than expected for example the removal of some of us from Zurich to Ulm

NOTICE: this is the author’s version of a work that was accepted for publication in Midwifery. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may

This technical report addresses the problem of automatically structuring linked document collections by using clustering. In contrast to traditional clustering, we study the clustering problem in the light of available link structure information for the data set (e.g., hyperlinks among web

be revised for subsequent publica‐ tions. Critical comments would be appreciated by the authors. Alle Rechte vorbehalten. Insbesondere die der Übersetzung, des Nachdru‐ ckes, des Vortrags, der Entnahme von Abbildungen und Tabellen – auch bei nur auszugsweiser Verwertung. All rights reserved. No part

This paper addresses the problem of semi-supervised classification on document collections using retraining (also called self-training). A possible application is focused Web crawling which may start with very few, manually selected, training documents but can be enhanced by automatically adding