一种新的基于贝叶斯频谱估计的传输线长度测量方法

根据双臂电桥原理搭建出实验电路进行数据采集,再应用贝叶斯频谱估计算法对测得的数据进行分析,得出反射频率周期,然后根据反射原理推算出人工传输线的长度。由于在检测方法和分析方法上的改进,在传输线长度的测量精度上获得了很好的效果。在实验中,根据先验知识和理论得出一个特定的模型方程;在实际应用中如果能够找到一个合适的模型方程,那么就可以运用贝叶斯频谱估计方法进行分析,因此贝叶斯频谱估计算法有着非常广泛的实用价值。     

Exchange-rate pass-through and market structure

We consider a situation in whichn firms located in market 1 andm firms located in market 2 each sell a commodity which is homogeneous within each market but may differ between markets. All firms sell on both markets. Each market has its own currency. The market demand functions differ. We give some basic results on the effects of exchange-rate changes and then show the following. When these markets are independent on the cost side (constant marginal costs) and demands are linear, a reduction in the number of firms (which might result from a merger) in market 1 increases the pass-through (of an appreciation of currency 2) in market 1 and decreases the pass-through in market 2. A similar occurrence in market 2 has the opposite effect. We give conditions under which, with identical economies of scope linking the markets, the sign of the price changes will be reversed when the number of foreign firms is small enough compared to the number of local firms. However, such sign reversals cannot occur in the two markets simultaneously.     

True indexes and rational habit formation

In this paper we discuss the construction of true indexes when tastes change endogenously. True indexes take the substitution possibilities of the consumer to a changing economic situation into account when equating the utility level of a particular period to the utility level attained in the base period through an appropriate change in income or the wage level. When tastes change endogenously, the current decision depends on the past history of consumption but, by the same token, the future path of consumption will depend on the current choice. In a true index, these intertemporal links of the current decision have to be taken into account. For a particular specification of the habit formation process, this is achieved by an appropriate transformation of prices and expenditures. A true intertemporal wage index is computed for the period 1946–1967 in the U.S. Because of increasing needs and intertemporal rationality, this index is roughly constant and equal to 1: real wages remained constant!     

Compulsive buying: Concept and measurement

This article investigates the probable causes of compulsive buying, proposes a conceptual framework to explain the phenomenon, and develops an appropriate measuring scale. The results of the analysis testify to the reliability and validity of the scale which was administered to 76 consumers.

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Begriffliche und empirische Erfassung von zwanghaftem Kaufverhalten

Zusammenfassung Der Beitrag behandelt zwanghaftes Kaufverhalten als einen besonderen Verhaltenstyp, der aus dem Zusammenwirken dreier Kräfte erklärt wird, nämlich erstens einer starken emotionalen Aktivierung, zweitens einer hohen kognitiven Kontrolle und drittens einer hohen Reaktivität. Der wichtigste Unterschied zwischen zwanghaftem und impulsivem Kaufverhalten wird in den kognitiven Vorgängen gesehen, die eine Person dazu führen, die Wiedererlangung des affektiven Gleichgewichtes mit einem Kaufakt zu assoziieren. Genauere Unterschiede zwischen verschiedenen Kaufverhaltenstypen bietet Figur 1. Die Zusammenhänge, die zur Entstehung von zwanghaftem Kaufverhalten führen, werden in Figur 2 gezeigt. Aus diesen Zusammenhängen ergeben sich drei Hypothesen, die empirisch geprüft werden:1. Der zwanghafte Käufer ist im allgemeinen in höherem Maße ängstlich als ein durchschnittlicher Käufer. 2. Der zwanghafte Käufer hat tendenziell ein schwächeres Selbstbewußtsein. 3. Der zwanghafte Verbraucher hat häufiger ein Elternteil mit mißbräuchlichem Verbraucherverhalten.Zur Prüfung dieser Hypothesen wird eine Skala entwickelt, die in Tabelle I beschrieben ist und deren Reliabilität und Validität sich als befriedigend erweist. Außerdem dürfte sie eindimensional sein. Die Daten, die von 38 zwanghaften Käufern und einer gleichgroßen Zahl von durchschnittlichen Käufern stammen, stützen die erste und die dritte Hypothese, die zweite Hypothese konnte nicht bestätigt werden.

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Gilles Valence and Alain d'Astous are Professors of Marketing, and Louis Fortier a graduate student, at the University of Sherbrooke, Sherbrooke, Québec J1K 2R1, Canada. The authors would like to thank Mr. Claude Sevigny (A.C.E.F. Estrie) and Mr. Claude Boucher (C.L.S.C. SOC), as well as Mrs. Monique Croteau, for graciously helping to track down compulsive buyers.This paper was first presented at the XVIIth Annual Conference of the European Marketing Academy, Bradford, England, April 5–8, 1988. A French version of the paper will be published in Recherches et applications en Marketing.     

Uncertainty,competition, and costs in corporate bond underwriting

The effect of a syndicate's uncertainty regarding the demand for a new bond issue on the syndicate's choice of an offer and bid price, and on the spread between those two prices, is analyzed. Then, the impact of uncertainty on the spread is empirically tested. The hypothesis that the spread varies inversely with the number of bidders for an issue is also developed and tested, and several other hypothesized determinants of the spread are examined.     

The Rise and Fall of Maya Civilization

Abstract . ‘Savages,’ as Europeans considered the Americans of ancient times, never built the great Mayan centers. The builders of great cities in Meso-America were a well-organized group with an adequate land base and a rather sophisticated technology. From 300 B.C. to 900 A.D. the Maya developed and perfected an agriculture-based economy with a well developed commerce, writing, art, science, religion and government, as well as an advanced architecture of monuments, palaces, temples and pyramids. Their civilization reached intellectual heights unique in the Western Hemisphere. What conditions caused its decline and fall? Interpreting the geographic and historical record in the light of the relevant social sciences, one can say a complex of circumstances: ecological abuse, exploitation of the working population, mismanagement, militarism, bad weather, famines, and epidemics.     

Ranking Research Productivity in Accounting for Asia-Pacific Universities

Using a set of 18 accounting journals and a sub-set of top five journals from 1991 to 2002, we rank the research productivity in accounting for a total of 119 Asia-Pacific universities. For the whole sampling period, the top five universities are the University of New South Wales, Hong Kong University of Science and Technology, Nanyang Technological University, the University of Sydney, and City University of Hong Kong. A number of prominent universities with long school history are not ranked in the top 20. During the second half of the sampling period, Hong Kong and Singaporean universities have shown the most improvement while some Australian universities have exhibited decline in research output. Also, Hong Kong University of Science and Technology replaces University of New South Wales as the first-ranked university in the period of 1997–2002. When compared with other North American universities, the accounting productivity of the top 20 Asia-Pacific institutions is comparable with that of leading universities in North America. The comparison is even more favorable to the Asia-Pacific universities during the period of 1997–2002.