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971.
The “tragedy of the commons” is the familiar problem that open access to a common property resource leads to overexploitation and to zero profits. A commons model is applied to an example of state sponsored private violence, the practice of privateering or licensed piracy. It is predicted that the presence of uncertainty about the value of the prey will reduce the amount of exploitation effort, and that industry profits may be positive due to both uncertainty and heterogeneous exploiters. Using data from England's wars with France and Spain between 1625 and 1630, the model suggests that the commons, represented by enemy merchant shipping, was not overexploited and that privateering profits were positive. The dynamic paths of privateering effort, ships seized, and individual firm profits were, however, consistent with the normal expectation that commons exploitation will peak and fall, as competition drives down returns through entry. “England was never richer than when at war with Spain.” Sir Edward Coke   相似文献   
972.
Vipond  Robert C. 《Publius》1993,23(3):39-56
On 26 October 1992, a majority of Canadians in a majority ofprovinces rejected the Charlottetown Accord in a national referendum.The accord capped the "Canada round" of constitutional negotiationsand attempted to satisfy Quebec, while also addressing otherpan-Canadian issues. The accord was defeated for different reasonsin different parts of the country. In Quebec, the "No" sideargued that the agreement did not meet their demands for greaterjurisdictionalautonomy within the federation. In the rest of Canada, the "No"side was particularly successful in demonstrating that the agreementdeviated from the principle of equality in the treatment ofindividuals and provinces. These critiques, inspired by differentvisions of the federation, lead in different directions. Inlight of these divisions, many commentators have suggested thatintergovernmental elites ought to abandon efforts of wholesaleconstitutional change. However, political developments in Quebecmay force these questions back onto the agenda.  相似文献   
973.
The author reviews current demographic trends in the countries of the European Community in the light of the efforts to abolish frontiers and border controls among member countries. She shows that there has been a general trend toward commonality in many aspects of demographic behavior.  相似文献   
974.
"Constitution of a trade bloc between Mexico, the United States and Canada through the North American Free Trade Agreement (NAFTA) in this decade has called attention to...the role of Mexico's southern border, Central American conflicts and migrations from that era. Relevant adjustments have been made to Mexico's policy in approaching problems regarding its southern neighbors. These changes respond largely to the perception held by larger economic blocs and migration generated by unequal development levels within these regions and countries." (SUMMARY IN ENG)  相似文献   
975.
Public preferences about the availability of abortion under various circumstances have remained fairly stable over time. Yet a standard CBS/New York Times abortion question indicates that a significant shift in opinion occurred during the 1980s, whereby the public became increasingly supportive of legalized abortion as it is now. These very different patterns of public opinion about abortion suggest that the public perceived a shift in the abortion status quo, toward more restricted access, over time, and became more supportive of current abortion policy.A model of support for legalized abortion as it is now is developed that incorporates the influences of court activities and interest-group behavior. The analysis indicates that the public reacted directly to the activities of the courts, becoming more supportive of current abortion policy in response to media coverage of court cases that challenged the abortion status quo and Supreme Court nominations and confirmations. Although absolute preferences remained largely unchanged, it appears the public perceived an increasing threat to the status quo and became correspondingly less enamored with further restrictions on the availability of abortion.  相似文献   
976.
977.
This article builds a composite index, the Central American Integration Index (IIC-AMPI), to measure economic integration. This index utilises a robust methodology and conceptual framework. The study shows that IIC-AMPI is responsive to variable changes and resistant to outliers. The findings indicate that the Deep Integration Process initiative dominates the current integration trend, as seen in the regional average score from 2015 to 2017, aligning with Guatemala and Honduras. Nicaragua demonstrates the most consistent progress, while Panama lags behind. The evidence supports the Customs Union as Central America's future integration path, highlighting the index's ability to capture the dynamic reality of economic integration.  相似文献   
978.
Measuring School-Related Stressors in Adolescents   总被引:2,自引:0,他引:2  
Some 1620 high school students responded to 68 items that measure adolescent stressors. Thirty-five of the items were based on J. P. Kohn and G. H. Frazer's Academic Stress Scale [1(1986) An Academic Stress Scale: Identification and Rated Importance of Academic Stressors, Psychological Reports, Vol. 59, pp. 415–426] developed in the United States, while the remaining 33 items were developed from P. Strutynski's [(1985) A Survey of Queensland Year 10, 11 and 12 Student Attitudes to Schools and Schooling, State Planning Committee, International Youth Year, Brisbane] lists of the most frequently named problems of 2336 Australian high school students. Confirmatory Factor Analysis was used to test and develop a measurement model developed from an extensive review of previous scales. The High School Stressors Scale emerged from the analytic process and measures nine school-related stressors. For researchers focusing on school-related problems and stressors among adolescents, the HSSS promises to be a very useful instrument. It has sound construct and predictive validity and adequate reliability, as demonstrated by the goodness-of-fit indices the squared multiple correlations.  相似文献   
979.
The aims of this study were (1) to compare the age-related expectations of parents and adolescents concerning the timing of achievement in a number of developmental tasks, (2) to examine whether personal characteristics of the adolescent affect developmental expectations, and (3) to examine whether discrepancies between the adolescents and the parents expectations are related to the amount of parent-adolescent conflict. The sample consisted of 508 families with adolescents (12–18 years old). During a home visit, a battery of questionnaires was administered individually to mothers, fathers, and adolescents. A new 24-item instrument to assess expectations for adolescents mastery of developmental tasks was developed for this study. Analyses showed that when the expectations of adolescents and those of their parents are compared at aggregate level, parents consistently indicate later ages for the achievement of developmental tasks than adolescents. Although parents have later timetables, parents and adolescents have strikingly similar views of the sequence in which achievement of developmental tasks should occur. The adolescents age appears to be the most potent predictor of developmental timetables, followed by gender, pubertal timing, and temperament, respectively. The amount of conflict within the parent-adolescent relationship was associated with differences in developmental expectations. The utility of the new instrument for research and clinical work is discussed.This research was supported by a grant from the Ministry of Health and Culture (PCOJ).  相似文献   
980.
The purpose of this study was to examine in a sample of 11,516 secondary school students the extent to which different behavioral, emotional and cognitive problems (a) reflected one or more underlying common factors; (b) actually cooccurred; and (c) were single problems. Principal Component Analyses were performed and percentagewise techniques were used. PCA demonstrated that one or more general syndromes could not by far account for all of the variance of the variables. The results suggest the existence of adolescent subgroups with divergent comorbidity patterns: those who primarily report one single symptom; those who report concurrent symptoms either exclusively in the category of behavioral problems or exclusively in the category of emotional and cognitive problems; and those who report concurrent symptoms in both categories. This distinction between different subgroups has important theoretical, diagnostic, and treatment implications.  相似文献   
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