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441.
随着数字技术的快速发展,数字化商业模式创新成为企业竞争的利器,而技术嵌入是企业内化数字技术支撑数字化商业模式创新的重要策略.本文基于飞贷金融科技的创新实践开展纵向案例研究,探究技术嵌入对数字化商业模式创新的影响.研究发现:技术嵌入包含技术整合和技术开发,两种策略在企业发展过程中经历了不同形式的演变.其中,拼凑式技术整合更有利于商业模式要素创新,而协奏式技术整合更有利于商业模式架构创新.利用式技术开发更有利于商业模式渐进创新,而探索式技术开发更有利于商业模式颠覆创新.最终,案例企业的数字化商业模式呈现出一条"流程信息化→渠道平台化→产品数字化→技术产品化"的进阶式演化路径,数字化程度相应呈现"类抛物线"的演变规律.本研究丰富了数字化商业模式创新的相关理论,并为科技型企业构建数字化商业模式提供了实践启示. 相似文献
442.
Sample size reestimation in a crossover, bioequivalence study can be a useful adaptive design tool, particularly when the intrasubject variability of the drug formulation under investigation is not well understood. When sample size reestimation is done based on an interim estimate of the intrasubject variability and bioequivalence is tested using the pooled estimate of intrasubject variability, type 1 error inflation will occur. Type 1 error inflation is caused by the pooled estimate being a biased estimator of the intrasubject variability. The type 1 error inflation and bias of the pooled estimator of variability are well characterized in the setting of a two‐arm, parallel study. The purpose of this work is to extend this characterization to the setting of a crossover, bioequivalence study with sample size reestimation and to propose an estimator of the intrasubject variability that will prevent type 1 error inflation. 相似文献
443.
Peter A. F. Fraser‐Mackenzie Tiejun Ma Ming‐Chien Sung Johnnie E. V. Johnson 《Risk analysis》2019,39(7):1560-1581
“Chasing” behavior, whereby individuals, driven by a desire to break even, continue a risky activity (RA) despite incurring large losses, is a commonly observed phenomenon. We examine whether the desire to break even plays a wider role in decisions to stop engaging in financially motivated RA in a naturalistic setting. We test hypotheses, motivated by this research question, using a large data set: 707,152 transactions of 5,379 individual financial market spread traders between September 2004 and April 2013. The results indicate strong effects of changes in wealth around the break‐even point on the decision to cease an RA. An important mediating factor was the individual's historical long‐term performance. Those with a more profitable trading history were less affected by a fall in cash balance below the break‐even point compared to those who had been less profitable. We observe that break‐even points play an important role in the decision of nonpathological risk takers to stop RAs. It is possible, therefore, that these nonpathological cognitive processes, when occurring in extrema, may result in pathological gambling behavior such as “chasing.” Our data set focuses on RAs in financial markets and, consequently, we discuss the implications for institutions and regulators in the effective management of risk taking in markets. We also suggest that there may be a need to consider carefully the nature and role of “break‐even points” associated with a broader range of nonfinancially‐focused risk‐taking activities, such as smoking and substance abuse. 相似文献
444.
展览业的发展一直是社会关注的热点,随着新常态的提出,城市展览业的发展也呈现出新常态。本文基于我国城市展览业发展的现状特点,提出在新常态背景下城市展览业发展的创新对策,以期为新时期下城市展览业的可持续发展提供一定的战略指导。 相似文献
445.
Human factors are widely regarded to be highly contributing factors to maritime accident prevention system failures. The conventional methods for human factor assessment, especially quantitative techniques, such as fault trees and bow-ties, are static and cannot deal with models with uncertainty, which limits their application to human factors risk analysis. To alleviate these drawbacks, in the present study, a new human factor analysis framework called multidimensional analysis model of accident causes (MAMAC) is introduced. MAMAC combines the human factors analysis and classification system and business process management. In addition, intuitionistic fuzzy set theory and Bayesian Network are integrated into MAMAC to form a comprehensive dynamic human factors analysis model characterized by flexibility and uncertainty handling. The proposed model is tested on maritime accident scenarios from a sand carrier accident database in China to investigate the human factors involved, and the top 10 most highly contributing primary events associated with the human factors leading to sand carrier accidents are identified. According to the results of this study, direct human factors, classified as unsafe acts, are not a focus for maritime investigators and scholars. Meanwhile, unsafe preconditions and unsafe supervision are listed as the top two considerations for human factors analysis, especially for supervision failures of shipping companies and ship owners. Moreover, potential safety countermeasures for the most highly contributing human factors are proposed in this article. Finally, an application of the proposed model verifies its advantages in calculating the failure probability of accidents induced by human factors. 相似文献
446.
447.
Bargaining for Success: Examining the Relationship Between Teacher Unions and Student Achievement
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While many previous studies have identified a positive relationship between teachers unions and student achievement on standardized tests, little research to date has explored the channels through which unions might actually affect achievement. Utilizing multilevel random intercept models, we examine the effects of two categories of items commonly negotiated in teacher contracts—“industrial union” items and “professional union” items—on individual student math scores. Further, we assess the ability of these two clusters of variables to explain the positive union effect found in previous research. The results confirm that teachers unions are positively associated with student achievement and suggest that the industrial model explains moderately more of the union effect than the professional model; however, only the combination of both models is capable of reducing the union effect to nonsignificance. These findings are also confirmed in a supplemental analysis utilizing instrumental variables to account for the possibility of endogeneity. Finally, a decomposition of the union effect suggests that teachers unions are most beneficial to middle‐ and high‐achieving students. We conclude that through industrial and professional bargaining, teachers are able to secure higher salaries, credentialing, and greater autonomy which lead to improved student achievement. 相似文献
448.
The current study evaluated whether training intraverbal naming would be sufficient to establish visual-visual matching-to-sample (MTS) performances in college students. In the first experiment, we used a multiple-probe design across stimulus sets to assess whether six participants could match arbitrary visual stimuli (AB) after learning to tact their two experimentally defined classes (A’ and B’) and then intraverbally relate their names (i.e., “A’ goes with B’”). All participants matched the stimuli accurately after training, as well as emitted the trained intraverbals. In the second experiment, we used a multiple baseline design across four participants to assess whether the same training would produce bi-directional intraverbals in the form of “B’ goes with A’,” and MTS performance consistent with symmetry (BA). All participants responded accurately during matching and intraverbal tests. Across both experiments, participants stated the trained intraverbals while performing the matching task. Results showed that MTS performance can be established solely by verbal behavior training. 相似文献
449.
随着无所不在的医疗保健时代的来临,人体局域网(BAN)受到了国内外研究人员的广泛关注。为了促进人体局域网技术的发展,IEEE 802.15-TG6小组拟定了BAN技术规范草案,该技术规范草案中定义了三个物理层:窄频带、超宽带、人体通信。本文将对BAN窄带物理层发射模型进行研究。BAN基带发射模型包括信道编码、扩频、交织、扰码、调制。根据草案提出的规范,搭建BAN基带发射浮点数模型,并对搭建的模型进行仿真验证。结果表明,在适当的信噪比情况下,搭建的基带发射浮点数模型得到了较理想的误码率,满足了BAN通信技术的要求,为后续BAN物理层研究打下了基础,同时也有利于整个BAN物理层基带的完善。 相似文献
450.
Adaptive and repeated cumulative meta‐analyses of safety data during a new drug development process
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Hui Quan Yingqiu Ma Yan Zheng Meehyung Cho Christelle Lorenzato Carole Hecquet 《Pharmaceutical statistics》2015,14(3):161-171
During a new drug development process, it is desirable to timely detect potential safety signals. For this purpose, repeated meta‐analyses may be performed sequentially on accumulating safety data. Moreover, if the amount of safety data from the originally planned program is not enough to ensure adequate power to test a specific hypothesis (e.g., the noninferiority hypothesis of an event of interest), the total sample size may be increased by adding new studies to the program. Without appropriate adjustment, it is well known that the type I error rate will be inflated because of repeated analyses and sample size adjustment. In this paper, we discuss potential issues associated with adaptive and repeated cumulative meta‐analyses of safety data conducted during a drug development process. We consider both frequentist and Bayesian approaches. A new drug development example is used to demonstrate the application of the methods. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献