Contributions in Merlin

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Modern statistical parsers are robust and quite fast, but their output is relatively shallow when compared to formal grammar parsers. We suggest to extend statistical approaches to a more deep-linguistic analysis while at the same time keeping the speed and low complexity of a statistical parser. The resulting parsing architecture suggested, implemented and evaluated here is highly robust and hybrid on a number of levels, combining statistical and rule-based approaches, constituency and dependency grammar, shallow and deep processing, full and nearfull parsing. With its parsing speed of about 300,000 words per hour and state-of-the-art performance the parser is reliable for a number of large-scale applications discussed in the article.

We study the topological structure of the network of shareholding relationships in the Italian stock market (MIB) and in two US stock markets (NYSE and NASDAQ). The portfolio diversification and the wealth invested on the market by economical agents have been shown in our previous work to have all a power law behavior. However, a further investigation shows that the inner structure of the capital control network are not at all the same across markets. The shareholding network is a weighted graph, therefore we introduce two quantities analogous to in-degree and out-degree for weighted graphs which measure, respectively: the number of effective shareholders of a stock and the number of companies effectively controlled by a single holder. Combining the information carried by the distributions of these two quantities we are able to extract the backbone of each market and we find that while the MIB splits into several separated groups of interest, the US markets is characterized by very large holders sharing control on overlapping subsets of stocks. This method seems promising for the analysis of the topology of capital control networks in general and not only in the stock market.

We suggest a simple asset market model in which we analyze competitive and strategic behavior simultaneously. If two-fund separation is found to hold across periods for competitive behavior, it also holds for strategic behavior. In this case the relative prices of the assets do not depend on whether the agents behave strategically or competitively. The agents acting strategically will however invest less in the common mutual fund. Constant relative risk aversion and the absence of aggregate risk are shown to be two alternative sufficient conditions for two-period fund separation. By including derivatives in our model, further strategic aspects arise. In this case the strategic behavior is found to differ from the competitive behavior even for utility functions leading to two-fund separation.

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In contemporary mode-based specifications, we typically find a naive combination of models of the externally visible behavior of a system (typically expressed as scenarios or use cases) and of the internal system behavior (partially represented in explicit state models and partially expressed as data). However, a systematic combination and integration of the two behavior aspects has not yet been investigated. In this paper, I sketch a systematic approach for modeling both external and internal behavior of a system with statecharts in an integrated, non-redundant way. The main idea is to start with statecharts that model external behavior in the form of use cases or type scenarios and then add statecharts that model internal behavior only where the scenario/use case statecharts do not suffice for expressing the behavior of the system.

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One important motive for deregulating social health insurance is to encourage product innovation. For the first time, the cost savings achieved by non-US managed care plans that are attributable to product innovation are estimated, using a novel approach. Panel data from a major Swiss health insurer permits to infer health status, which can be used to predict health care expenditure. The econometric evidence suggests that the managed care plans benefit from risk selection effects. In the case of the health maintenance organization (HMO) plan, however, the pure innovation effect may account for as much as two-thirds of the cost advantage.

Im Gegensatz zu den USA ist die schweizerische Hochschullandschaft noch immer alles andere als hierarchisiert. Professor Egon Franck ist überzeugt, dass sich dies indes durch die BolognaReform ändern wird. Mit dem Ordinarius für Betriebswirtschaftslehre an der Universität Zürich unterhielt sich NZZRedaktor Jan Mühlethaler.