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排序方式: 共有469条查询结果,搜索用时 15 毫秒
1.
This paper considers the extent to which price and income proxy variables help in forecasting tourist demand in Spain. Contrary to some recent studies, we found that the inputs' contribution in terms of fitting and forecasting is nil when compared with alternative univariate models. Whether these findings are the results of the restrictions embedded in building the proxy inputs or in a poor specification of the dynamics of these models remains to be seen. We also contend that when dealing with medium, long-term forecasting comparisons, the use of the traditional aggregate accuracy measures like RMSE and MAPE help very little in discriminating among competing models. In these situations, predicted annual growth rates may be a better alternative. 相似文献
2.
贾玉林 《中小企业管理与科技》2020,(6):185-186
目前,倾斜摄影测量作为一种新技术,经过不断的探索、应用和发展,已开始在测绘行业中大显身手,并取得了不小的成绩。通过三维模型进行的矢量数据采集,其矢量精度完全依赖于三维模型精度。论文以实践经验为基础,定性地分析了在航空摄影、像控测量、模型生产三阶段中,影响模型精度的因素,希望对三维模型的生产起到一定的指导作用。 相似文献
3.
Rick J. Parent Tiffany Noël Hib Rebecca A. Silver Carrie Jenkins Margaret P. Poe R. Jacob Mullins 《Technological Forecasting and Social Change》2005,72(4):171-411
Two experiments examined the effects of iterated polling and feedback on prediction accuracy for volatile world events using the Delphi paradigm. In both experiments, participants predicted rapidly changing geopolitical events. The first experiment occurred during the litigation surrounding the Clinton/Lewinsky affair in 1998. Results indicated that feedback improved individual and group accuracy for predictions of whether an event would occur. These types of predictions derived from group consensus were approximately 90% accurate, which was significantly higher than the average individual participant's accuracy. Neither polling nor feedback had much effect on time course predictions. The second experiment occurred during the American military action against the Taliban regime in Afghanistan in 2001. In Experiment 2, participants were polled three times to determine if increasing the number of iterated polls would improve Delphi accuracy. The results showed that accuracy improved from the first to the second poll but not from the second to the third. The groups predicted whether these scenarios would occur with approximately 75% accuracy, which was significantly higher than the accuracy of any individual participant. Once again, the Delphi procedure did not enhance time course predictions in Experiment 2. 相似文献
4.
Tristan Roger 《Accounting & Business Research》2018,48(6):651-673
Previous studies document that forecast accuracy impacts analyst career outcomes. This paper investigates the influence of forecast accuracy on coverage assignments. I show that brokerage houses reward accurate analysts by assigning them to high-profile firms and penalise analysts exhibiting poor accuracy by assigning them to smaller firms. The coverage of high-profile firms increases the potential for future compensation linked to investment banking and trading commissions. In addition, covering such firms increases analysts' recognition from buy-side investors, which, in turn, increases the likelihood of obtaining broker votes and votes for the Institutional Investor star ranking. Overall, my results indicate that high forecast accuracy leads to increased future compensation. 相似文献
5.
电磁流量与示踪相关流量组合测井仪及其应用 总被引:1,自引:0,他引:1
在对电磁流量与示踪相关流量组合测井仪的基本原理、井下仪器结构、仪器工作方式、技术指标等内容进行详细阐述的基础上,进一步运用测井实例分析了电磁流量与示踪相关流量组合测井仪能把电磁流量计、示踪相关流量计、同位素吸水剖面测井仪组合到一起,使附加井温、压力、磁性定位等参数相互印证,得出准确的综合解释结果,从而为油田监测提供准确可靠的测井资料,具有一定的现实意义。 相似文献
6.
对油田企业分区块计量问题的现状进行了分析,指出了目前存在计量误差的主要原因,针对费希尔Ex8300质量流量计在使用中存在的缺陷,重新引进了新型CMF纯油质量流量计,报告了在多个原油集输站的试验情况,通过试验比对,找出了产生系统误差的根本原因,提出了在分队、分区块计量中质量流量计的应用是可行的,并告戒仪表管理人员对质量流量计的输入参数的动态变化要进行适时调整,以保证仪表的计量准确。 相似文献
7.
8.
本文对选煤厂建设工程投资估算中影响准确性的因素进行了分析,并结合BP神经网络理论基于Matlab软件对选煤厂带式输送机及栈桥单位工程进行了数值模拟,通过对比数值模拟结果与概算指标估算结果,详细阐述了可以提高选煤厂建设工程投资估算准确性的几点建议。 相似文献
9.
当今,学术界的引文不规范行为十分严重。针对于此,本文主要概括了引文不规范行为的分类、原因和解决对策,强调引文在科技论文中的重要作用,并从作者自身、期刊社和相关法律制度三个方面解决该问题。 相似文献
10.
为避免单一勘探方法的多解性,提高勘探的准度与精度,在某区的物探找水实践中,综合运用高密度电阻率法,对称四极电测深法、电阻率测井三种方法进行勘探,查明目标井位附近区域的岩性,推断地层的含水性,并根据勘探结果划定钻井布设的合理位置。 相似文献