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41.
Radiocarbon dates are presented for distinctive types of British Late Neolithic pottery, identifying questions which cannot yet be resolved.  相似文献   
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ABSTRACT. Boyce et al. (1981, 1983) have proposed and implementd the use of observed entropy levels to estimate the travel-cost coefficient in mathematical programming models of network equilibrium which involve logit route-choice probabilities. This so-called “dispersion-constrained” model is shown to give severely biased and statistically inefficient underestimates. A natural counterpart, the entropy-maximizing model, is proposed here and overestimates the travel-cost coefficient with much lower bias and much higher statistical efficiency. Even though the two models are mathematically homeomorphic in some respects, they have vastly different statistical properties. It follows that the use of observed entropy levels is undesirable and should be avoided, since maximizing entropy provides an unambiguously superior alternative.  相似文献   
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In this article, we study the U.S. Senate to understand how legislators' previous experiences in elected office influence their political behavior. We posit that, as a result of their experiences in office, former governors in the Senate are less partisan than their colleagues. We code the political jobs held by senators between 1983 and 2015 and analyze the effects of these careers on party loyalty in Senate floor votes. We find that gubernatorial service is associated with a 7–8% decrease in Party Unity. We test several hypotheses for the observed “governor effect” and find that, relative to their colleagues, former governors are supported by donor networks that are less ideologically extreme. We conclude that the unique experiences associated with serving as governor, along with the personalized nature of governors' electoral support coalitions, affect a senator's relationship with the party. Ultimately, our analysis illuminates how personal attributes, such as prior experience in elected office, can inform the study of legislative behavior.  相似文献   
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ABSTRACT RELU is a dynamic general equilibrium model of a metropolitan economy and its land use, derived by unifying in a theoretically valid way, models developed by one of the authors [ Anas (1982) , Anas–Arnott (1991, 1997) , Anas–Kim (1996) , Anas–Xu (1999) ]. RELU equilibrates floor space, land and labor markets, and the market for the products of industries, treating development (construction and demolition), spatial interindustry linkages, commuting, and discretionary travel. Mode choices and equilibrium congestion on the highway network are treated by unifying RELU with the TRAN algorithm of stochastic user equilibrium [ Anas–Kim (1990) ]. The RELU‐TRAN algorithm's performance for a stationary state is demonstrated for a prototype consisting of 4‐building, 4‐industry, 4‐labor‐type, 15‐land‐use‐zone, 68‐link‐highway‐network version of the Chicago MSA. The algorithm solves 656 equations in a special block‐recursive convergent procedure by iterations nested within loops and loops within cycles. Runs show excellent and smooth convergence from different starting points, so that the number of loops within successive cycles continually decreases. The tests also imply a numerically ascertained unique stationary equilibrium solution of the unified model for the calibrated parameters.  相似文献   
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No political observer, politician, or political scientist doubts that party polarization has weakened the social fabric of Congress. Measuring that effect, however, is exceedingly difficult. In this article, we operationalize the congressional social fabric by examining the foreign travel behavior of members of Congress over time. We evaluate the social disintegration in Congress by examining if and whether changes in member travel can explain why the social connectedness of members has waned. Using a unique dataset of foreign travel for House members from 1977 to 2012, we find that Republican House members, in particular, have altered their foreign travel patterns. Ideologically extreme members have always been less likely to take foreign trips, but extremely conservative Republican have become much more likely to travel only with co-partisans as polarization has increased in Congress. Ideologically moderate Republicans, while still traveling as members of bipartisan delegations, have also increased their willingness to travel only with fellow Republicans. Our results suggest that bipartisan foreign travel is a victim of the partisan war waging in Congress.  相似文献   
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