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Content analysis is a very tedious method of data collection. This paper addresses once more the question of whether and how computers may be used to facilitate content analysis in the coding stage. To interpret natural language automatically a computer program must be able to unravel the syntactical structure of sentences (‘parsing’) and to trace their semantical meaning by dealing with textual context (= ‘co-text’), prior knowledge (context outside the text) and semantic variability (different or ambiguous meanings of words and phrases). Several approaches to enable computer programs to perform these tasks are discussed, including approaches from the fields of cognitive psychology and artificial intelligence. The conclusion should be that it is still impossible to enable computer programs to perform all these tasks. But there are possibilities for using computer programs to support human coders both in the coding stage and the data-analysis stage of content analysis. As an example the program CETA to perform Computer-aided Evaluative Textual Analysis is discussed.  相似文献   
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In the article, we study two different ways of forming multipartner alliances between firms with the central idea that procedure is an important factor in multipartner alliance formation. In the first procedure, an alliance is formed simultaneously, while in the second procedure (step-by-step) members are added one by one. In the model we present, each firm is assumed to have a multidimensional maneuvering space, which consists of all alliance positions acceptable to the firm, and an ideal position in this space. Alliances will form between the firms whose maneuvering spaces overlap. The results of the analysis confirm that procedure is an important factor in multipartner alliance formation. Nevertheless, if ideal positions of firms are acceptable to all alliance partners, then the result of alliance formation does not depend on procedure. In addition, it is shown that it can be disadvantageous to be a first mover. Finally, we are able to provide sufficient conditions under which one procedure is preferred in a three-partner case. More specifically, a firm with its ideal position acceptable to the two other firms may prefer the simultaneous procedure to being a late mover if (1) there is a certain balance in the firms' degree of flexibility and their power and (2) if the agreed alliance position of the two other firms is acceptable to the firm in question.  相似文献   
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In this work, for a reference filtration \(\mathbb {F}\), we develop a method for computing the semimartingale decomposition of \(\mathbb {F}\)-martingales in a specific type of enlargement of \(\mathbb {F}\). As an application, we study the progressive enlargement of \(\mathbb {F}\) with a sequence of non-ordered default times and show how to deduce results concerning the first-to-default, \(k\)th-to-default, k-out-of-n-to-default or all-to-default events. In particular, using this method, we compute explicitly the semimartingale decomposition of \(\mathbb {F}\)-martingales under the absolute continuity condition of Jacod.  相似文献   
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This paper measures the ensuing changes in productivity in the French pig sector following the introduction of the European regulation addressing water pollution by nitrates from agriculture. Productivity is measured using the Malmquist–Luenberger index. The sources of changes in productivity observed are examined by breaking down this index into its technical progress and efficiency components. The results show that in the early stages, increases in productivity were stimulated by increased efficiency, before being driven by technical progress. The estimations regarding the sources of efficiency gains for the farms in the sample (technical efficiency, efficiency of scale and environmental efficiency) are then used to estimate the indirect costs and benefits (or negative costs) linked to the introduction of the environmental regulation controlling the disposal of organic manure and the management of nitrogen surplus from pig farms. The existence of a “win-win” effect as regards the Porter hypothesis relation between efficiency and environmental regulation is highlighted for the French pig sector.   相似文献   
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This paper studies the impact, on no-arbitrage conditions, of stopping the price process at an arbitrary random time. As price processes, we consider the class of quasi-left-continuous semimartingales, i.e., semimartingales that do not jump at predictable stopping times. We focus on the condition of no unbounded profit with bounded risk (called NUPBR), also known in the literature as no arbitrage of the first kind. The first principal result describes all the pairs of quasi-left-continuous market models and random times for which the resulting stopped model fulfils NUPBR. Furthermore, for a subclass of quasi-left-continuous local martingales, we construct explicitly martingale deflators, i.e., strictly positive local martingales whose product with the price process stopped at a random time is a local martingale. The second principal result characterises the random times that preserve NUPBR under stopping for any quasi-left-continuous model. The analysis carried out in the paper is based on new stochastic developments in the theory of progressive enlargements of filtrations.  相似文献   
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