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121.
ABSTRACT This paper develops a model of regional financial markets which can encompass different degrees of spatial financial integration. The behavior of the system is analyzed under alternative assumptions about the time frame of analysis and the extent of the flexibility of interest rates. It is argued that links may exist between regional real and financial sectors even in the short run and that such links must, through the regional balance of payments, exist in the long run, even where there is perfect financial spatial integration. It is observed that these relationships have generally been ignored by regional economic model builders. 相似文献
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J. A. J. Gowlett 《Journal of World Prehistory》1987,1(2):127-170
Accelerator mass spectrometry (AMS) allows radiocarbon dating to be carried out by direct counting of14C atoms, rather than the conventional counting of radioactive disintegrations. The result is that samples up to 1000 times smaller can be handled. The approach was tested in principle by 1977 and for archaeological operation by 1983. More than 2000 samples per year are now being dated worldwide. The machines can now operate to about ± 80 years or better. Dates older than 40,000 years have not yet been achieved, but the ability to use small samples has already had considerable impact on dating the period 10,000–30,000 years ago. Bone is an ideal material for the new technique, since amino acids can normally be isolated and purified from gram-size samples. Studies of the origins of domestication are aided by the dating of individual grains and seeds. Because small samples can be mobile in the soil, careful sample selection strategies and procedures are required. The full impact of the technique can be assessed only through the rapid and comprehensive publication of archaeological results. 相似文献
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This paper critically reviews the existing literature on multiple-trip journeys, and clarifies the need for an improved conceptualization and modeling strategy. It also suggests different ways that trip chaining can be treated and a theory constructed. Exploratory studies, from the 1960s and 1970s, are briefly surveyed (Section I). While they developed the existence and complexity of travel patterns, they lacked any comprehensive theoretical framework. However, they were useful in that they supported the conceptual framework of various kinds of stochastic processes used by transportation scientists to replicate trip-chaining behavior (Section II). Scientists subsequently improved their conceptualization of the issue by grounding individual behavior on the principle of utility maximization. In this latter area the economists have emphasized theoretical concerns while transportation researchers have emphasized operationality (Section III). 相似文献
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This paper is concerned with the reciprocal relationship between migration and development in Third World settings. Using individual-level data for Venezuela, migration behavior is related to a person's age, educational attainment, gender, and characteristics of his/her place(s) of residence as an out-migrant, in-migrant, or stayer. Place characteristics are in terms of four groups based on employment patterns: the core, regional centers, resource frontiers, and traditional rural areas. Four questions are of concern. First, does development influence migration? All analyses indicate this is so. Second, does migration influence development? Findings are ambiguous in that places experiencing improvement in their mix of human capital lagged in the net number of persons obtained through migration whereas a gain in numbers was accompanied by deterioriation in human capital profiles. Third, was incipient polarization reversal occurring in Venezuela in the late 1960s, early 1970s? This paper departs from the usual approach by addressing this question in terms of human capital attributes instead of population aggregates. On this basis, polarization reversal is in evidence, particularly in regional centers. Finally, this study answers in the affirmative that places with different development characteristics generate migration streams differing in type, magnitude, explanation, and impact. 相似文献