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11.
A separation between the academic subjects statistics and mathematical statistics has existed in Sweden almost as long as there have been statistics professors. The same distinction has not been maintained in other countries. Why has it been kept for so long in Sweden, and what consequences may it have had? In May 2015, it was 100 years since Mathematical Statistics was formally established as an academic discipline at a Swedish university where Statistics had existed since the turn of the century. We give an account of the debate in Lund and elsewhere about this division during the first decades after 1900 and present two of its leading personalities. The Lund University astronomer (and mathematical statistician) C. V. L. Charlier was a leading proponent for a position in mathematical statistics at the university. Charlier's adversary in the debate was Pontus Fahlbeck, professor in political science and statistics, who reserved the word statistics for ‘statistics as a social science’. Charlier not only secured the first academic position in Sweden in mathematical statistics for his former PhD student Sven Wicksell but also demonstrated that a mathematical statistician can be influential in matters of state, finance as well as in different natural sciences. Fahlbeck saw mathematical statistics as a set of tools that sometimes could be useful in his brand of statistics. After a summary of the organisational, educational and scientific growth of the statistical sciences in Sweden that has taken place during the last 50 years, we discuss what effects the Charlier–Fahlbeck divergence might have had on this development.  相似文献   
12.
This paper examines whether the ex post relative payoffs of peers as well as the size of the peer group impact an agent's willingness to take risks. For example, persons in a flood plain may be less likely to purchase flood insurance if their neighbors also refrain from purchasing. We generalize the Fehr‐Schmidt (1999) model to allow the intensity of the social preferences to vary with the size of the peer group. Our experiment tests whether subjects are more or less likely to choose a lottery over a fixed payment when others have been assigned either the same lottery or the fixed payment. Using both between and within subject designs, we find risk‐taking behaviour is not responsive to the risks faced by others regardless of the size of peer group.  相似文献   
13.
当前小体积远端射频单元(Remote Radio Unit,RRU)主要是皮站级别的Pico-RRU,其重量和体积仍然难以满足掌上型的要求。为此,采用高集成度的AD9361芯片来实现长期演进(Long Term Evolution,LTE)宽带收发信机功能,配合时钟同步模块、放大器模块和控制接口电路等一起构建低成本的掌上型RRU。主要解决了基于AD9516的时钟同步、低相位噪声设计和高灵敏度接收机设计三个技术难点,成功实现了掌上型、高性能、低成本的设计目标。整个RRU样机尺寸为18 cm×10 cm×2 cm,质量约500 g,量产成本千元以内。测试表明,该RRU下行误差向量幅度(Error Vector Magnitude,EVM)小于3%,优于3GPP要求的8%;10 MHz带宽时上行接收机灵敏度优于3GPP要求的-93.5 dBm。  相似文献   
14.
The authors set out to determine the brain dominance characteristics of students enrolled in business statistics courses in a historically Black university in a major southeastern Texas city. Thereafter, the authors investigated the relationship between a student’s brain hemispheric preference and academic performance in college courses, which emphasize problem solving. The results reported in this study reveal that left brain– and right brain–dominant students are at parity when it comes to performance in a problem-solving course. Moreover, both left brain– and right brain–dominant learners perform better than whole-brain dominant learners in a problem-solving course.  相似文献   
15.
Why are some constitutions amended frequently and others hardly at all? An obvious candidate determinant is constitutional rigidity, i.e., the size and number of procedural barriers to amendment. Given some demand for amendment, greater rigidity implies a smaller supply. However, measures of rigidity often do not correlate significantly (or even with the predicted sign) with amendment rates. Ginsburg and Melton (2015) argue that amendment culture – “shared attitudes about the desirability of amendment” – is a more important determinant of amendment rates. We study up to 128 constitutional episodes from 54 countries and estimate relationships between amendment rates and Hofstede cultural indices. Cultures that are more individualistic and less prone to uncertainty avoidance are associated with higher amendment rates. When cultural dimensions are controlled for, the lagged amendment rate (Ginsburg and Melton’s proxy for culture) is not a robust correlate.  相似文献   
16.
国防工程发展建设至今,基本已经趋于健全,其包含万千,由众多部分组成。在国防工程的众多组成部分之中,对于城市以及民众具备有重要意义的人防工程就不可不提,其存在是将深埋地下的空间与资源进行最大化发掘及利用,从而做到与其他国防工程组成部分契合,实现立体化国防工程的建设发展。人防工程虽然不显于人前,但其重要性却无人可以忽略,其对于城市建设发展、民众生命利益保障奠定着坚实基础。  相似文献   
17.
18.
近年来,随着我国经济的迅速发展,电气工程技术标准不断提升,对于技术的优化提出了更高的要求。电气工程技术在各行各业都得到了有效的应用,该技术的重要性不言而喻。尤其是制造业,其对于电气工程技术的依赖程度较高。所以在电气工程以及电气自动化控制系统的优化中,如何提高运行效率以及让设备稳定运行是当前工程师们所必须考虑的问题。  相似文献   
19.
为实现工程造价精细化管理目标,需要各个环节的相互配合来达到资源优化配置。BIM技术依托虚拟建模技术,实现了对工程项目的数字化建造管理。实践证明,将BIM技术融入项目工程造价管理体系中,有助于提升工程造价管理的整体质量。论文立足工程造价精细化管理的内涵,剖析了BIM技术在工程造价精细化管理中的应用价值,并提出了BIM技术在工程造价精细化管理中的具体应用策略。  相似文献   
20.
以江西省宜春市"月都花溪谷"乡村森林旅游项目规划中哲学元素的应用为个案,结合哲学理论进行分析。结果表明:乡村森林旅游项目规划应有哲学的自觉,根据项目所在地自然和人文资源禀赋,因地制宜地吸收哲学元素,从而打破乡村森林旅游项目同质化和见物不见人的困局,赋予乡村森林旅游项目以特色和灵魂。因此,提出突破森林旅游项目规划中一元化的经济思维定势、以哲学思维唤起人学意义、因地制宜激发内生式哲学文化活性等启发性建议。  相似文献   
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