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1.
ABSTRACT. The distribution of above-median income groups can be described accurately by OLS regression of the Pareto distribution. The excellent fit of log-linear regression has led some researchers to conclude that extrapolated income measures in the open end of the distribution are reliable. The analysis of income distribution data for metropolitan areas reveals: (1) that OLS tends to consistently overestimate the number of families in the tail, and (2) that the overestimation can have serious implications for hypothesis testing.  相似文献   
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ABSTRACT This paper analyzes the determination of industry structure in a product market, given a monopolistic factor market. The characteristics of industry structure examined include the number of firms, their pricing and locational pattern. It is shown how a monopolistic factor owner–a landowner–structures the product market in order to extract maximum rent. Asymmetry characterizes the resulting locational pattern. All the product market firms charge different prices in equilibrium. No matter how large the number of firms competing in the product market, the landowner can always guarantee himself positive profits. The paper concludes with a discussion of possible applications and tests of the theory.  相似文献   
3.
The contribution of animal protein to the ancient Maya diet, and its means of procurement, can be assessed more accurately on the basis of systematic faunal recovery from recent excavations. We evaluate the presence of dog (Canis familiaris) remains in Preclassic (1200 BC-AD 250) deposits from the Maya site of Cuello, Belize, and conclude that the animals were raised for food and killed at the end of their first year of life. The frequency and distribution of canid bones suggest a significant but not dominant contribution to the meat supply throughout the Preclassic period.  相似文献   
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Reviews     
“JINNAH: CREATOR OF PAKISTAN.” by Hector Bolitho. John Murray. London, 7954. Pp. x and 244, illus.

“WANTED: AN ASIAN POLICY,” by Edwin O. Reisehauer. New York: Knopf, 7955. Pp. 256.  相似文献   

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This study attempts to determine if there was Roman lead mining in Africa Proconsularis, approximately the area of modern day Tunisia, using lead isotope analysis. Another important aspect of the study is the innovative use of electron microprobe analysis (EMPA) as a screening tool to greatly reduce the number of expensive lead isotope analyses needed for the study. The EMPA X-ray mapping for arsenic, antimony, copper, and silver narrowed the sample of curse tablets to those most likely produced from Tunisian ores; these tablets were then tested using thermal ionization mass spectrometry (TIMS) analysis. A total of 96 Roman lead curse tablets from Carthage, Tunisia were screened with EMPA and twenty selected for TIMS to determine the ore sources of the lead used to manufacture the tablets. Comparing the lead isotope ratios of twelve of the sixteen tablets most likely to be made of Tunisian lead to samples of Tunisian ores suggests that the Romans were mining lead in Africa Proconsularis and were not relying solely on imports.  相似文献   
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