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排序方式: 共有803条查询结果,搜索用时 31 毫秒
1.
Background: Validation of overall survival (OS) extrapolations of immune-checkpoint inhibitors (ICIs) during the National Institute for Health and Care Excellence (NICE) Single Technology Assessment (STA) process is limited due to data still maturing at the time of submission. Inaccurate extrapolation may lead to inappropriate decision-making. The availability of more mature trial data facilitates a retrospective analysis of the plausibility and validity of initial extrapolations. This study compares these extrapolations to subsequently available longer-term data.

Methods: A systematic search of completed NICE appraisals of ICIs from March 2000 to December 2017 was performed. A targeted search was also undertaken to procure published OS data from the pivotal clinical trials for each identified STA made available post-submission to NICE. Initial Kaplan-Meier curves and associated extrapolations from NICE documentation were extracted to compare the accuracy of OS projections versus the most mature data.

Results: The review identified 11 STAs, of which 10 provided OS data upon submission to NICE. The extrapolations undertaken considered parametric or piecewise survival models. Additional data cut-offs provided a mean of 18 months of OS beyond the end of the original data. Initial extrapolations typically under-estimated OS from the most mature data cut-off by 0.4–2.7%, depending on the choice of assessment method and use of the manufacturer- or ERG-preferred extrapolation.

Conclusion: Long-term extrapolation of OS is required for NICE STAs based on initial immature OS data. The results of this study demonstrate that the initial OS extrapolations employed by manufacturers and ERGs generally predicted OS reasonably well when compared to more mature data (when available), although on average they appeared to underestimate OS. This review and validation shows that, while the choice of OS extrapolation is uncertain, the methods adopted are generally aligned with later-published follow-up data and appear appropriate for informing HTA decisions.  相似文献   

2.
With regional science now into its seventh decade, it is timely to step back and look at what regional science is about, the past challenges it has faced, particularly its relevance, and to identify some of the challenges it has confronted in the past and at present. The paper demonstrates regional science research has had, and continues to have, policy relevance, as well as being relevant for business, and has addressed important issues. It provides an overview of recent commentaries on issues regional scientists might now be addressing.  相似文献   
3.
We present the sparse estimation of one-sided dynamic principal components (ODPCs) to forecast high-dimensional time series. The forecast can be made directly with the ODPCs or by using them as estimates of the factors in a generalized dynamic factor model. It is shown that a large reduction in the number of parameters estimated for the ODPCs can be achieved without affecting their forecasting performance.  相似文献   
4.
This study examines how market timing can affect host market reaction to cross-border seasoned equity offerings (SEOs), an event generally viewed unfavorably by investors. We assume that firms engage in market timing in response to valuation uncertainty (VU), home market uncertainty (HMU) and/or host market uncertainty (HSU), and that raising capital abroad faces higher scrutiny costs and familiarity bias from host market investors. We conjecture that timing strategies provide signals that vary in strength to host market investors and that dual-timing strategies may strengthen an existing signal. Our hypotheses are tested on a sample of 190 cross-border SEOs that were issued on the U.S. stock market between 1990 and 2017 by firms from 29 countries. Using event study methodology, we find that market timing based on VU is negatively related to host market valuation and that a dual-timing strategy with HMU or HSU generally produces a stronger signal. Our results have practical relevance for stock markets that suffer from high uncertainty; we estimate that a high VU firm with a $1 billion valuation suffers a drop of $31.3 million in market valuation during a high host market uncertainty (high HSU) compared with low host market uncertainty (low HSU).  相似文献   
5.
ABSTRACT

Prospect theory is widely thought to be one of the best-confirmed accounts of human decision-making under risk. There are numerous claims in the literature that various kinds of nonexperimental, observational evidence provide strong support for prospect theory. We investigate the veracity of these claims using a set of philosophy of science morals and a careful delineation of models of choice under risk, focussing on the extant versions of prospect theory and their various components. We challenge the claim that prospect theory is well supported because it explains the equity premium puzzle. In addition, we analyse a major international survey thought to support prospect theory and argue that the support is questionable, both for statistical reasons and because the evidence itself is mixed. Our analyses highlight some important ideas in the philosophy of science and caution against strong claims about support for prospect theory that rely on nonexperimental, observational evidence.  相似文献   
6.
Death is inevitable; yet, not all consumers prepare for death by purchasing end‐of‐life (EOL) products. Using the theory of reasoned action (TRA) and the dual‐process model framework, this study aims to examine the role of emotions and cognitions in influencing consumers' decisions to engage in planning for death. A mixed methodology design was used. Study 1, a qualitative study, uncovered positive and negative emotions and deliberative reasoning that comprise consumers' EOL purchase decision process. Study 2, a quantitative study, confirmed that emotions and deliberations independently and jointly influenced consumers' EOL attitude and behavior and that emotions affected deliberations for both prepaid funerals and wills. Subjective norms outperformed attitude in predicting both products' purchase behavior. These finding supported the dual‐process model of behavior and the TRA in the EOL research context and contributed to the EOL literature by investigating the effects of emotions and deliberations concurrently; thus validating the important role of emotions in influencing EOL planning and purchase. In light of our findings, marketers could, after due cognizance of the morbidity and sensitivity of the topic, develop actionable promotional and segmentation strategies for EOL products and other emotion‐laden, unsought products and service.  相似文献   
7.
孙烨珩 《科技和产业》2020,20(12):227-232
针对传统的离职预测算法应用于现实中高维度小样本不平衡数据集时存在准确度低、易过拟合、鲁棒性差等问题,应用梯度增强集成分类器CatBoost算法,进行类别型特征处理,利用BOHB(Bayesian Optimization and Hyperband)寻找最优参数,结合交叉验证对模型分类性能进行评估,建立分类模型并对护士离职情况进行预测。该算法采用高维小样本不平衡特征的上海部分公立医院的护士离职数据集,并与XGBoost、随机森林、支持向量机进行对比。实验结果表明,该算法准确度高,鲁棒性强,能够有效地对护士离职进行预测。  相似文献   
8.
Based on social capital theory and the family-firm context, this paper studies familiness' composition and the result of the overlap of the family and firm systems, analysing their influence on the internationalisation strategies of family firms. In this relationship, the stakeholder engagement becomes at the same time an antecedent and a result when developing family businesses' strategies, being one of the most relevant the internationalisation strategies. Prior research focused on familiness as the result of proxy variables such as the percentage of ownership and management in family hands, or business size, instead of as psychological variables resulting from shared organisational culture and social interactions. Through a qualitative study based on 12 interviews of general managers and/or export managers of Spanish family olive oil mills, this study asserts that the level of familiness influences internationalisation strategies, the reasons underlying a business becoming international and its commitment to activities abroad being the role of stakeholders crucial in those interactions. The higher the level of familiness, the more likely the family business internationalisation and the higher their levels of international commitment. Additionally, the higher the concern about their stakeholders, the higher their levels of international commitment. The family businesses' concern for their stakeholders and their international commitment share a reciprocal relationship. The results regarding the relevance of familiness as social capital resources in sustaining competitive advantages support the decision to promote, develop and nurture social capital when a family business goes international.  相似文献   
9.
Netnography is constantly evolving as technologies and access to online data develop. Our paper outlines how large data sets of social media can be analysed through bridging the divide between the small, rich and contextually nuanced data that is the hallmark of netnography and the scope and scale of data made possible through social media listening conventions. We define this approach as netnographic sensibility and with the use of a short case study discuss the process through which social media data could be gathered, triangulated and analysed. We orientate the paper around two interrelated questions: investigating how netnographic insights can be extended using social media monitoring tools, and asking how this can be used to add richness and depth to understanding mass consumer realities. Our contribution complements the widely established methodological approach of netnography as we argue that netnography has the capacity and capability to embrace technological advances within the domain of social listening to add value for academic researchers.  相似文献   
10.
Customer experience (CX) is an aggregate of consumer touch points that can be brand-owned (completely controlled by the firm), partner-owned (collectively controlled by the firm and one or more of its partners), customer-owned (where the firm or its partner cannot exert any control or influence) or represented by social/external touch points that account for the importance of the roles of others in the customer experience process. Although the concept of CX is widely used, not much has been examined about how external touch points impact customer perception of experience. Therefore, the main purpose of this study is to examine the role and impact of internal and external touchpoints as dimensions of customer experience and how CX can impact consumer word-of-mouth intention. Service outcome and peace of mind were used to represent internal experience touchpoints and peer to peer quality (PTP) was used to represent an external experience touchpoint. A total of 293 usable surveys were used for analysis using a Bayesian model developed for this study instead of the more traditional SEM approaches. Results showed that an external experience touchpoint has a similar impact to those of internal experience touchpoints in the experience process. CX was also found to have a strong effect on customer word of mouth intention. These findings make various contributions to the literature on CX, especially to research differentiating internal from external experience touchpoints. On the practical side, this study provides recommendations to retailers about how to manage an external touchpoint.  相似文献   
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