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971.
How and under what circumstances can adjusting the inflation target serve as a stabilization-policy tool and contribute to welfare improvement? We answer these questions quantitatively with a standard New Keynesian model that includes cost-push-type shocks. Our proposed inflation target rule calls for the target to be adjusted in a persistent manner and in the opposite direction to the realization of a cost-push shock, which is essentially a makeup strategy. The inflation target rule, combined with a Taylor-type rule, significantly reduces inflation fluctuations originating from cost-push shocks and mitigates the stabilization trade-off, resulting in a similar level of welfare to that associated with the Ramsey optimal policy.  相似文献   
972.
In this paper, we propose a goal-based investment model that is suitable for personalized wealth management. The model only requires a few intuitive inputs such as size of wealth, investment amount, and consumption goals from individual investors. In particular, a priority level can be assigned to each consumption goal and the model provides a holistic solution based on a sequential approach starting with the highest priority. This allows strict prioritization by maximizing the probability of achieving higher priority goals that are not affected by goals with lower priorities. Furthermore, the proposed model is formulated as a linear program that efficiently finds the optimal financial plan. With its simplicity, flexibility, and computational efficiency, the proposed goal-based investment model provides a new framework for automated investment management services.  相似文献   
973.
通过单因素及正交实验,比较高产米曲霉在摇床培养与发酵罐培养中生产曲酸的发酵工艺参数。结果表明,在温度为23℃、发酵天数为9 d、接种量为25%、菌龄为96 h时,摇床发酵的曲酸产量达到最高,最高可达98.6 g·L-1;而发酵罐培养的最佳工艺条件是温度23℃、发酵天数4 d,接种量15%,菌龄96 h时,此条件下曲酸产量可达到99.6 g·L-1。本研究为工业化生产曲酸提了供理论依据。  相似文献   
974.
为贯彻《古生物化石保护条例》,提高济南市古生物化石保护水平,在对区内古生物化石资源进行野外勘查和综合整理的基础上,依据古生物化石鉴定结果及其赋存地层分布特征,得出济南市古生物化石的分布特征,划分了古生物化石产地,选择化石完整程度、富集程度、剖面出露程度、周边地质环境、工程活动影响五个评价因子,运用综合指数法,建立了符合济南实际的古生物化石保护区划分体系,将区内古生物化石产地进行了保护区分级,并按照“保护优先,结合实际”的原则,制定了符合济南市实际的古生物化石保护措施。  相似文献   
975.
Online complaints have become increasingly influential on the purchasing behavior of customers in recent years. In an effort analyze large quantities of textual complaints and detail the various aspects of them, Aspect-Based Sentiment Analysis was looked to as an ideal framework to take on the task. This study set out to synthesize specific service failure items and categorize them into the groupings related to the hotel guest cycle and the corresponding operations, then compare the patterns of expression used by Asian and Non-Asian guests as the related their hotel experiences. A total of 390,236 online complaint terms posted about 353 hotels in the UK by hotel guests from 63 nations were manually derived from TripAdvisor for analysis. With consideration given to the homophily theory, we posited that Asian and non-Asian guests would exhibit similarities and differences with respect to the service failures they encountered when presented with various items of service. The results confirmed this as Asian guests were shown to encounter more service failures with respect to the engineering segment of operations (e.g. hotel room equipment issues), while non-Asian guests encountered more service failures on the housekeeping end of operations (e.g. toilets, public areas, cleanliness, and bedding). By organizing the failures according the four stages of the guest cycle, it was observed that approximately 80% of the service failures occurred during the occupancy period. This study contributes to the existing literature on hotel guest satisfaction both with respect to the methodology it uses and the new findings it presents on differences in perceptions of service failures members among different cultures.  相似文献   
976.
在旅游业高质量快速发展的背景下,全面厘清与掌握省域尺度范围各旅游节点在网络中的角色和地位,并解析其网络结构效应具有重大意义。针对现有研究因旅游流数据采集限制而较少对团队游空间结构研究的不足,基于云南省旅游包车客运信息,运用社会网络结合空间分析的方法,提取了云南省团队游网络空间结构特征,并对其聚散效应进行分析。结果表明:云南省团队游整体网络密度较小且淡旺季表现出相似特征,网络对各节点的旅游联系与合作影响尚未显现,暴露出云南省团队游旅游市场发展的不均衡;团队游网络外向中心势显著高于内向中心势,网络空间集聚趋势明显;通常具有较强外向中心性的旅游节点同时也具有较强内向中心性,表现出“集中—发散”的聚散规律;旅游节点的聚散效应表现为单个节点以圈层状向外递减形式发生,其扩散路径主要集中于文山—蒙自、景洪—思茅方向。整体上,云南省区域旅游业发展差异明显,应重点加强滇西南与滇西旅游区、滇中与滇东北旅游区的旅游资源开发与合作。  相似文献   
977.
This study aims to investigate the corporate social responsibility (CSR) practices of international hotel chains operating in China and their effects on local Chinese employees. As CSR practices vary across countries and contexts, this study developed a scale of CSR metrics, which was based on CSR reports published by international hotel chains in China and a comprehensive literature review. Subsequently, the proposed model, which depicts the relationships between CSR practices and local employee work metrics, was tested with a PLS-SEM. Multiple phases of qualitative and quantitative investigations of 2451 local Chinese employees of international hotel chains allowed for validating a formative construct of CSR with four dimensions: environment protection, employee wellness, business ethics, and customer wellness. The PLS-SEM results confirmed the significant effects of CSR practices of international hotel chains in China on local Chinese employee engagement, commitment, job satisfaction, and organizational citizenship behaviors. Theoretical and practical implications are presented.  相似文献   
978.
We extend the Frankel–Wei approach by using wavelet analysis to evaluate the relative importance of the dollar and the renminbi as anchor currencies at different time scales. We find that Asian currencies’ co-movement with the dollar weakened after the global financial crisis, while that with the renminbi strengthened particularly after China introduced a new exchange rate management system in 2015. The evidence suggests that emerging Asian economies have recently attached more importance to the renminbi as an anchor in exchange rate management.  相似文献   
979.
In this article, the quantile time–frequency method is utilized to study the dependence of Chinese commodities on the international financial market. The impacts of risk management and diversification benefits of different portfolios are examined by calculating the reduction in downside risk. Moreover, we estimate and compare Sharpe Ratios (SRs) and Generalized Sharpe Ratios (GSRs) based on the frequencies of the investigated portfolios. Our empirical results reveal a strong asymmetric response from Chinese commodity markets. Specifically, we find that gold is a safe-haven asset, and due to negative correlations found at lower quantiles in medium and long term, an increase in the USD index damages bull commodity markets but boosts bear conditions under long-term investments, and negative (positive) tail correlations with interest rates (IRs) in bull (bear) markets are observed. It is proven that WTI can decrease short-run risks while USD and GOLD are more efficient in the diversification of downside risk. Adding international commodities may not improve the returns of Chinese commodities at given risk levels in the short and medium term through SRs and GSRs. In brief, investors should consider these dependence structures and modes of risk management in terms of time and frequency.  相似文献   
980.
This paper estimates the causal effect of fiscal rules on fiscal balances in a panel of 142 countries over the period 1985–2015. Our instrumental variable strategy exploits the geographical diffusion of fiscal rules across countries. The intuition is that reforms in neighboring countries may affect the adoption of domestic reforms through peer pressure and imitational effects. We find that the mere existence of fiscal rules correlates with lower deficits, but the positive link disappears when endogeneity is correctly addressed. However, when considering the strength of rules through a continuous index of fiscal rules’ design, we show that well-designed rules have a statistically significant impact on fiscal balances. We conduct several robustness tests and show that our results are generally robust and not affected by weak instrument problems.  相似文献   
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