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1.
This study aimed to describe the distribution of injury mechanisms and to assess the impact of those mechanisms on the morbidity and mortality of trauma. All patients admitted to Puerto Rico Trauma Hospital (2002–2011) for road-traffic collisions (RTCs, 5,371), gunshot wounds (GSWs, 2,946), falls (2,319), pedestrian accidents (1,652), and stab wounds (SWs, 1,073) were selected. Gunshot victims were 1.19 (95%CI: 1.07–1.33) times as likely as road-traffic victims to have an ISS ≥25. Pedestrians were 1.76 (95%CI: 1.49–2.09) times more likely to have a GCS ≤8 than road-traffic victims were. The risk of dying was 2.64 (95%CI: 2.20–3.16) times higher for gunshot victims and 1.51 (95%CI: 1.23–1.86) times higher for pedestrians compared to patients who had had RTCs. Gunshot victims and pedestrians had the worst clinical outcomes. Accordingly, these patients should receive the most aggressive clinical management. Furthermore, it is imperative to develop public health campaigns on trauma prevention.  相似文献   
2.
Abstract

The purpose of this study is to analyse the new processes of tourism growth and its conflicts from the perspective of social movements. First, the urban growth machine analysis model is applied by the systematisation of six projects. Second, the resistance movements against those projects and whether this resistance could be the start of local tourism degrowth policies are examined. The methodology is qualitative, based on documentary analysis, participatory observation, discussion groups and interviews. The case study is the destination of Costa del Sol-Málaga. The results enable the development of the urban growth machine model in tourist destinations. Meanwhile, social movements demystify the argument based on neoclassical economic progress. The social movements condemn the effects of large-scale top-down projects, and implement alternative bottom-up proposals. Although the social movements do not reject tourism, they call for greater control over its impact, denounce unlimited growth, overtourism and the loss of urban quality of life. These movements advocate a lifestyle linked to the everyday space, which they believe is threatened by excessive urban-tourism growth. They are a symptom of the need to devise a proposal using the principles of degrowth.  相似文献   
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Using high-frequency data for major volatility indexes, we compute the volatility of volatility and show that its logarithm follows a fractional Brownian motion with Hurst parameter smaller than 1/2 thereby extending to the volatility asset class the recent findings obtained for the equity index markets. The results confirm that the volatility of volatility is a rough process and it possesses the long memory property. We also show that the correlation between the volatility and the volatility of volatility is positive, consistent with observations in the volatility option market. Lastly, a robustness check using volatility futures confirms the findings.  相似文献   
5.
This paper examines the effects of inward FDI on economic growth across the Spanish regions over the period 1996–2013, paying particular attention to the ‘headquarters effect’, namely that FDI is not always registered where it is effectively made but in the region in which the firm’s headquarters is located. By estimating a panel Spatial Durbin Model to allow for the detection of spatial spillovers, two main findings are reported. First, FDI does foster economic growth. Second, only when the headquarters effect is properly addressed do spatial spillovers arise. Hence, this effect is masking the impact of regional FDI spillovers on growth, which affects the reliability of the results and, consequently, FDI policies choice. Importantly, the results are: a) robust to the way of computing the headquarters effect; b) independent of the spatial weight matrix specification; and c) confirmed when splitting FDI into different industrial and service branches.  相似文献   
6.
Two-part models based on generalized linear models are widely used in insurance rate-making for predicting the expected loss. This paper explores an alternative method based on quantile regression which provides more information about the loss distribution and can be also used for insurance underwriting. Quantile regression allows estimating the aggregate claim cost quantiles of a policy given a number of covariates. To do so, a first stage is required, which involves fitting a logistic regression to estimate, for every policy, the probability of submitting at least one claim. The proposed methodology is illustrated using a portfolio of car insurance policies. This application shows that the results of the quantile regression are highly dependent on the claim probability estimates. The paper also examines an application of quantile regression to premium safety loading calculation, the so-called Quantile Premium Principle (QPP). We propose a premium calculation based on quantile regression which inherits the good properties of the quantiles. Using the same insurance portfolio data-set, we find that the QPP captures the riskiness of the policies better than the expected value premium principle.  相似文献   
7.
Hotels can strengthen their competitiveness by expanding their innovation process beyond the boundaries of the firm to exploit the valuable knowledge and skills of their customers. This study examines the effects of new service (NS) co-creation with customers in the hotel industry on NS performance, as well as the moderating role of top management support. The research also explores the main barriers faced by hotels to co-create service innovations. Partial least squares structural equation modelling results indicate that Customer co-creation exerts a direct impact on NS market outcomes and NS development (NSD) speed, which in turn favours NS quality. NS quality translates into better NS customer-related outcomes as well as in improved NS market outcomes. Top management support enhances the effect of Customer co-creation on the NSD speed. The main barrier to NS co-creation in hotels is to find customers interested in devoting time to this activity or with the appropriate knowledge and experience.  相似文献   
8.
The identification of the causal effects of educational policies is the top priority in recent education economics literature. As a result, a shift can be observed in the strategies of empirical studies. They have moved from the use of standard multivariate statistical methods, which identify correlations or associations between variables only, to more complex econometric strategies, which can help to identify causal relationships. However, exogenous variations in databases have to be identified in order to apply causal inference techniques. This is a far from straightforward task. For this reason, this paper provides an extensive and comprehensive overview of the literature using quasi‐experimental techniques applied to three well‐known international large‐scale comparative assessments, such as PISA, PIRLS or TIMSS, over the period 2004–2016. In particular, we review empirical studies employing instrumental variables, regression discontinuity designs, difference in differences and propensity score matching to the above databases. Additionally, we provide a detailed summary of estimation strategies, issues treated and profitability in terms of the quality of publications to encourage further potential evaluations. The paper concludes with some operational recommendations for prospective researchers in the field.  相似文献   
9.
Although NPD collaboration with external partners has become the next generation in NPD practice, the discussion concerning how to organize collaboration so as to obtain better results is far from over. Since communication is the most important element in successful interfirm exchange, this study focuses on the impact of collaborative communication and its facets—frequency, formality, reciprocal feedback, and rationality—on NPD collaboration results. In order to explain how collaborative communication can best be managed to enhance NPD collaboration results, this research combines the relational and resource‐based views, proposing the existence of two routes of influence: the direct resource‐based route and the indirect relational route mediated by trust. Using a sample of 207 NPD collaboration projects of innovative firms, empirical findings indicate that reciprocal feedback–rationality and frequency play an important role in product quality and adherence to budget and schedule, respectively, even without trust. Moreover, the trust between partners substantially reinforces the positive influence of reciprocal feedback–rationality on NPD collaboration results and makes the effect of formality significant. Therefore, the two alternative routes are confirmed as important paths to new product success, which provides relevant managerial implications.  相似文献   
10.
In the first phase of pharmaceutical development, and assuming that the probability of positive response increases with dose, the main statistical goal is to estimate a percentile of the dose–response function for a given target value Γ. We compare the Maximum Likelihood and centred isotonic regression estimators of the target dose and we discuss several performance criteria to assess inferential precision, the amount of toxicity exposure and the trade-off between them for a set of some exemplary adaptive designs. We compare these designs using graphical tools. Several scenarios are considered using simulation, including the use of several start-up rules, the change of slope of the dose-toxicity function at the target dose and also different theoretical models, as logistic, normal or skew-normal distribution functions.  相似文献   
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