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31.
The defining properties of party identification long established for the United States fail with some frequency to be replicated in electoral systems abroad. A number of plausible suggestions have been made to account for this system-level variability: Most of these have some face merit, but none taken alone is adequate to provide a full cross-system explanation. Variation in party system size or fractionalization has recently been discussed as another source of differential dynamics of party loyalties. Unfortunately, the conventional means of assessing party identification properties are subject to rather severe artifacts, typically ignored, when comparisons are made across systems of very different party size. The conceptual stakes underlying key methods options for such comparisons—most notably, between continuous and discrete statistical tools—are examined. The use of continuous statistics for systems of very multiple parties rests on an assumption that voters do in some degree regard these party systems as imbedded in a continuous space. A simple test for this assumption is mounted in four systems and unsurprisingly it shows very clear support. Analysis of residuals beyond this obvious result add several points of less obvious information about the distribution of party affect in such systems. 相似文献
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He has served as a consultant to the president’s Foreign Intelligence Advisory Board, the National Security Council, and related
agencies of the U.S. government. He has written, coauthored, or edited over sixteen books on intelligence and national security. 相似文献
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Evaluation of laser desorption mass spectrometry and UV accelerated aging of dyes on paper as tools for the evaluation of a questioned document 总被引:1,自引:0,他引:1
Laser desorption mass spectrometry (LDMS) may be used for the detection and identification of dyes found in inks. Naturally-aged and artificially-aged blue and black ballpoint pen inks containing the cationic dye methyl violet were analyzed on paper. The average molecular weight of the dye sample was calculated from LD mass spectral data and plotted versus time. The resulting aging curves demonstrate that, as dye degradation increases, the average molecular weight of the dye decreases. Typical variables involved in ink aging, such as the type of paper and ink formulation, were investigated. Results show that these variables influence the rate of dye degradation. Furthermore, UV accelerated aging has been developed and tested as an alternative to thermal approaches. 相似文献
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Among the unforeseen problems of the new industrial age has been the disposal of increasing quantities of wastes—many hazardous and toxic. Industrial chemistry has produced numerous products that, while useful, are alien to nature and resistant to biodegradation or detoxification. Growing public awareness of the possible hazards and risks involved in disposal of the residuals of industrial activities is arousing a popular demand for environmental protection. But this popular awareness depends upon public information and a degree of scientific literacy—conditions which vary widely among nations. Initial consequences are environmental regulations and restrictions respecting waste disposal in scientifically developed countries, and vulnerability among less developed countries to the export of hazardous wastes from the countries of their origin. A secondary consequence is the emergence of international waste trade as a national and international multidimensional policy problem. 相似文献
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