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Evidence today suggests that by at least 8000 to 8500 B.P., Archaic hunter-gatherer economies were established throughout the North American Southwest. The Early Archaic seems to be a period of considerable variability across the subregions; this may be a product of currently slim knowledge of the period, or it may indicate that the region witnessed considerable flux. With the Middle Archaic period from 5500 to 3500 B.P. there seems to be greater similarity in material culture across the region and a definite increase in the number of known sites. Finally, the Late Archaic/Early Agricultural period from 3500 to 2000 or 1500 B.P. sees the establishment of a mixed farming-foraging economy in much of the Southwest with apparently major changes in subsistence-settlement systems. Preagricultural Archaic land use patterns are known in broad outline but not in detail; high mobility by small social groups in an annual round would have permitted exploitation of diverse biotic communities. In most parts of the region, significant socioeconomic change accompanies the incorporation of agriculture into the late preceramic period, as witnessed by the appearance of longer-term residential sites with pitstructures and storage features.  相似文献   
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The Victorian Agendas Project (1991-93) used a snowball sampling method to produce annual peer-nominated lists of agenda-setters and policy influentials in six policy fields: economic policy, health, welfare, transport, education and the environment. Three hundred and fifty-six interviews were conducted with 214 influentials over the three-year period. Respondents identified high-priority issues and policy options on their current and future agendas. This paper deals with the question of who the agenda setters/policy influentials were. Was there evidence of a dominant elite or elites (e.g. business and banking elites) whose influence ranged across policy fields, or was there a more pluralist pattern in which influentials tended to 'specialise' in particular fields? How substantial was the turnover among influentials when the Liberal-National coalition government replaced Labor in 1992?  相似文献   
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Frey (1995) noted that California generated two, separate outmigration streams. The first stream was composed of “negatively selected” migrants, or those with low education and low income levels. These migrants usually selected destinations in neighboring states such as Washington, Oregon, or Colorado. The second stream was more typical of interstate migration flows. Migrants were typically better educated, had higher incomes and destinations that were more national in scope (positively selected). The purpose of this paper is to evaluate the income selectivity of outmigrants from California. It was hypothesized that poorly educated migrants are negatively self-selective and the better educated would be positively self-selective. Using data derived from the 1990 PUMS data file, this paper studies the effects of expected wage differentials in determining the selectivity of outmigrants from California. Self-selectivity is accounted for in the modeling process via a two-stage estimation procedure, since estimated returns to migration based on a comparison of individual migrants may be biased due to self-selection. Results reveal no significant or systematic selectivity of the better educated migrants, while self-selection was more important among the poorly educated nonmigrants.  相似文献   
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Behavioral ecologists combine evolutionary models of mechanism and ecological models of circumstance to analyze the origins and forms of intragroup exchange among social foragers, a category that includes primates, hominids, and recent and modern hunter-gatherers. Evolutionary mechanisms encompass individual, sexual, reciprocal, kin, group, and cultural selection; models of circumstance include tolerated theft, scrounging, marginal value, trade, show-offs, and risk reduction. After a critical review, I develop a partial synthesis of these models. The results show that exchange behaviors have multicausal origins and they likely will be diverse due to differing combinations of mechanism and circumstance. They also help explain seemingly unique features of foraging economies, including constrained production and routine demand sharing.  相似文献   
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