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排序方式: 共有1403条查询结果,搜索用时 15 毫秒
1.
This paper examines how movie producers recruit directors in the preproduction phase as mutual choices in a two-sided matching model. It conceptualizes that movie attributes and filmmaker characteristics determine the matching outcomes (“who directed which movie”) and in turn indirectly affect movie box office. We exploit a dataset of 4,807 feature films from 1990 to 2010 to examine empirically the complementarities between the movie/producer side and the director side in terms of movie budget, filmmaker track records and social relations. A series of simulations suggest that social relations facilitate positive assortative matching. Further simulation analyses are conducted to quantify the financial implications of movie–director mismatches, as well as the indirect effects of production budget and producer characteristics. The simulation results show that: a) the financial implications of having a mismatched director can be substantial; and b) the indirect effect of production budget and producer characteristics affect movie box office in an interactive manner. These findings can help filmmakers to better understand the financial impacts of movie–director choices and make more informed decisions at the early phase of preproduction.  相似文献   
2.
It is difficult to predict the financial distress of unlisted public firms due to their longer disclosure cycle of accounting information and more inadequate continuity of market trading information compared to listed firms. In this paper, we propose a framework to predict the financial distress of unlisted public firms using current reports. Specifically, to better represent the meaning of current report texts, we propose a semantic feature extraction method based on a word embedding technology. Empirical results show that current reports contain more effective information for predicting the financial distress of unlisted public firms compared with periodic reports. In addition, semantic features extracted using our proposed method significantly improve the predictive performance, and their enhancing effect is superior to that of topic features and sentiment features. Our study also provides implications for stakeholders such as investors and creditors.  相似文献   
3.
The spread of the COVID-19 pandemic has resulted in the launch of contactless delivery services. This research integrates resource matching, service quality evaluation, and perceived value theories to explore the factors that promote the use contactless delivery services. The data was obtained through questionnaire surveys, and research hypotheses were verified through the structural equation modelling approach. With the exception of convenience, the results show that privacy, reliability, security, and flexibility have a significantly positive effect on consumers' intention to use “contactless” delivery services through consumers' perceived value. This study contributes to the literature by introducing theoretical frameworks from various paradigms and enriches the academic research on existing theoretical structure models. It also helps optimize resource allocation and realize the social environment related to coexisting with the COVID-19 pandemic.  相似文献   
4.
为了解决宏蜂窝与飞蜂窝构成的两层异构网络上行干扰与资源分配问题,提出了一种在认知型飞蜂窝的双层异构网中结合子信道分配和功率控制进行资源分配的框架。通过对异构网中跨层干扰问题进行分析与建模,将求解最优子信道分配矩阵和用户发射功率矩阵作为干扰管理问题的解决方法。模型中认知型飞蜂窝网络子信道和飞蜂窝网络用户构成非合作博弈,双方利用效用函数最优值进行匹配,构成初始信道分配矩阵;再由接入控制器根据接入条件从初始信道分配矩阵中筛选用户,并优化接入用户的发射功率矩阵,得到最优子信道分配矩阵和功率矩阵。仿真结果表明,优化框架提高了双层异构网络中飞蜂窝网络用户的吞吐量和接入率,降低了异构网中跨层干扰。  相似文献   
5.
We analyze the effect of worker inflows on establishments’ productivity, using German data. Previous studies for other countries have found positive effects of hiring workers from superior (more productive or higher paying) firms. Ranking establishments by their median wage, we find that inflows from inferior establishments seem to increase hiring establishments’ productivity. Further empirical analyses suggest our findings are due to a positive selection of such inflows from their sending establishments. These workers might have to find a better job match in order to advance their careers, an interpretation supported by the finding that the effect is driven by workers with short tenure at their previous employer. Our findings reflect the increasingly assortative pattern of worker mobility in Germany found in a related strand of literature.  相似文献   
6.
桑叶配方颗粒迄今尚没有统一的质量标准。为提升桑叶配方颗粒的内在质量,对其物质基准评价方法进行了研究。选取具有代表性产地的15批桑叶制备物质基准,采用高效液相色谱法,以芦丁、异槲皮苷、紫云英苷作为评价指标,确定桑叶物质基准的出膏率范围、标志性成分含量及转移率范围,采用超高效液相色谱法,建立物质基准UPLC特征图谱,并对其主要成分进行指认。结果表明:15批物质基准中,芦丁转移率为19.94%~34.05%,异槲皮苷转移率为11.67%~43.58%,紫云英苷转移率为10.73%~43.05%;物质基准特征图谱中,标定了14个共有峰,指认出7个色谱峰,分别为新绿原酸、绿原酸、咖啡酸、芦丁、异槲皮苷、槲皮素-3-O-(6″-O-丙二酰基)-β-D-葡萄糖苷、紫云英苷。所建立的基准评价方法为桑叶配方颗粒质量标准的制定及其后续大规模生产提供了数据基础。  相似文献   
7.
ABSTRACT

As service-oriented computing is commonly used in industrial systems to deal with the continually changing business environment, matching processes with existing services becomes one of the most important phases in constructing, integrating and optimizing information systems. The precision of semantic service matching becomes a critical factor in ensuring the correctness of functionalities in system processes. However, the dependability of semantic service matching cannot be warranted in complex contexts. To improve semantic service matching for industrial systems, a context-based semantic service matching approach named ‘Process-Based service MatchMaker’(PBMM) is proposed in this paper. It selects the suitable services for the process from candidate services through taking the dependencies of related services process into consideration.  相似文献   
8.
危浪  文求实  喻红艳  王畅 《科技和产业》2019,19(12):136-140
产业转型升级发展对专业技能型人才的需求发生变化,作为技能型人才重要培养主体的高职院校,面临着如何培养新时代高素质技能人才的挑战。通过招聘大数据挖掘电子商务技能型人才的需求特征,同时调研相关高职院校电子商务专业人才培养现状,分析供需匹配度。结果表明:电商企业需要德技并修的高素质技能型人才,而高职院校的课程体系以专业技能、商务技能等硬技能教学为主,忽视综合素养软技能教育,同时,高职院校电子商务专业课程开设未能根据行业技术更新和产业转型发展及时调整。基于研究结果,从课程体系建设、校企合作深化、工匠精神培育等方面提出相关建议。  相似文献   
9.
土地流转对农户贫困脆弱性的影响研究   总被引:2,自引:0,他引:2  
研究目的:探究土地流转对农户贫困脆弱性的影响,为防范农户陷入贫困和解决农村贫困提供理论和实证依据。研究方法:本文借助2016年湖北省1682个农户实地调查数据,基于倾向得分匹配法(PSM)和回归方程的Shapley值分解法,分别考察国定贫困线、1.9美元贫困线和3.1美元贫困线下不同类型土地有无转出和转出面积对农户贫困脆弱性的影响。研究结果:土地转出能够显著降低农户的贫困脆弱性,且农户贫困脆弱性随着转出土地面积的增加而降低;从土地转出的异质性来看,水田转出对缓解农户贫困脆弱性的效果更为明显,旱地转出的效果次之。研究结论:应进一步加快农村土地流转,释放农村剩余劳动力,不断增加农户收入,从而降低农户贫困脆弱性。  相似文献   
10.
In this paper, we investigate the factors that influence youth labour market expectations and outcomes. We also perform a job matching exercise to understand youth labour market dynamics in Sub-Saharan Africa. Our results show that youth education is an influential factor of youth employment expectations and employment, ceteris paribus. Higher educational attainments have a great impact on expecting and securing better jobs, particularly in the technical and professional fields. Youth with low educational attainments, particularly primary education and lower, have a higher tendency to expect to be employed in occupations with low job complexity. Our results indicate a severe job-skill mismatch in all occupational categories, both before and after the youth’s transition into the labour market. Using education as the only selection criterion, we found that less than 10 per cent of employment expectations match with skills required while 55 per cent and 34 per cent are under or over-educated for the jobs expected, respectively. Over and under education is a notable feature in youth labour markets in Sub-Saharan Africa. About 47 per cent of employed youth in the sample are overqualified for their respective jobs while 28 per cent are under qualified.  相似文献   
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