Contributions in Merlin

Temporal aggregation is a crucial operator in temporal databases and has been studied in various flavors, including instant temporal aggregation (ITA) and span temporal aggregation (STA), each having its strengths and weaknesses. In this paper we define a new temporal aggregation operator, called parsimonious temporal aggregation (PTA), which comprises two main steps: (i) it computes the ITA result over the input relation and (ii) it compresses this intermediate result to a user-specified size c by merging adjacent tuples and keeping the induced total error minimal; the compressed ITA result is returned as the final result. By considering the distribution of the input data and allowing to control the result size, PTA combines the best features of ITA and STA. We provide two evaluation algorithms for PTA queries. First, the oPTA algorithm computes an exact solution, by applying dynamic programming to explore all possibilities to compress the ITA result and selecting the compression with the minimal total error. It runs in O(n2pc) time and O(n2) space, where n is the size of the input relation and p is the number of aggregation functions in the query. Second, the more efficient gPTA algorithm computes an approximate solution by greedily merging the most similar ITA result tuples, which, however, does not guarantee a compression with a minimal total error. gPTA intermingles the two steps of PTA and avoids large intermediate results. The compression step of gPTA runs in O(np log(c + ?)) time and O(c + ?) space, where ? is a small buffer for ""look ahead"". An empirical evaluation shows good results: considerable reductions of the result size introduce only small errors, and gPTA scales to large data sets and is only slightly worse than the exact solution of PTA.

Increased globalization and the consequent dispersion of IT activities across the world have driven the growth of global IT outsourcing. The share of offshore software development (OSD) in the high-cost countries has grown tremendously in the past years and this trend will continue in the coming years. Software development projects continue to experience poor performance problems because of their inherent complexities and the uncertainties involved from the start. Although OSD projects offer cost advantages, the unique risks related to cultural, linguistic and geographic differences, knowledge transfer and project management make OSD more vulnerable to failure than domestically outsourced projects. This paper explores the early warning signs (EWS) of failures in OSD projects, a concept that can be employed as an early warning system to avoid failures. Using the Delphi survey method, we intend to find out the most important EWSs specific to OSD projects. Our panelists include 23 experts primarily from the offshore client and vendor companies in Switzerland and India. We discuss four offshore-relevant EWS categories and the preliminary results of this ongoing research from the third survey phase.

Für die Zürcher Banking-Professorin Christine Hirszowicz sind die Attacken der USA und der EU gegen Steueroasen reine Symptombekämpfung. Ursache der Kapitalflucht seien zu hohe Steuertarife in den Ursprungsländern. Der Schweiz rät sie, auch bei Steuerhinterziehung Rechtshilfe zu leisten, sonst aber hart zu bleiben.

This paper examines, numerically, the impact of a negative exogenous shock to marginal productivity (such as ecological government regulation that becomes effective at some point in time) in an endogenous finite time growth model with sluggish reallocation of human capital. The policy can be anticipated or unanticipated by the economic agents, and it can also be announced but not implemented. It turns out that these frictions have very strong long-run effects on consumption and output, and on the optimal allocation of capital and labor in particular. The qualitative properties are closely related to those found in homogenous labor models with positive productivity shocks. The numerical optimization method employed here proved very successful in qualitatively similar problems in engineering but has not yet found its way into macroeconomic models of growth.

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Klassische Publikationsmodelle für wissenschaftliche Fachinformationen werden zunehmend durch unterschiedliche Formen des digitalen Publizierens ergänzt bzw. teilweise verdrängt. Vor dem Hintergrund dieser Entwicklung ist insbesondere die Idee des Open Access von grosser Bedeutung. Dieser Beitrag liefert einen Überblick über den aktuellen Stand und geplante Aktivitäten im Bereich von Institutional Repositories bei Hochschul- und Forschungseinrichtungen in der Schweiz.

In this paper we have argued for a new conceptualisation of strategic foresight. The existing approaches are largely based on too simple a concept of future. It is usually assumed that one is able to conceptualise already in the present all possible future developments. We contrast this with the concept of a 'radically open' future, which might develop in ways which go beyond of what our cognitive categories allow us to conceptualise. Drawing on linguistic philosophy it is shown how our thinking and communicating is limited by our linguistic categories. Strategic foresight from this perspective is largely concerned with the adjustment of the linguistic system to novel developments of the world. This requires openness towards new linguistic categories. Drawing on the philosophical concepts of 'anticipating critique' by Paul Feyerabend and 'occasional reason' by Helmut Spinner we try to show how such openness can be accomplished.

This paper uses data on German consumer magazines observed between 1992 and 2004 to analyze the extent to which consumers (dis-)like advertising. We estimate logit demand models separately for the six most important magazine segments in terms of circulation. We find little evidence for readers disliking advertising. On the contrary, we show that readers in many magazine segments appreciate advertising. Readers of Women's magazines, Business and politics magazines as well as Car magazines — market segments where advertisements are relatively more informative — appreciate advertising while advertising is nuisance to readers of Adult magazines, a segment where advertisements are particularly uninformative. Demand for interior design magazines is not well identified. Our logit demand estimates are confirmed by logit demand models with random coefficients and by magazine-specific monopoly demand models.