State‐Dependent Forward Guidance and the Problem of Inconsistent Announcements

Forward guidance can be provided as an unconditional promise, i.e. commitment to a specific low policy rate. Alternatively, the promise may include an escape clause, i.e. a condition defining the state of the economy under which the central bank would not keep such a low rate and, instead, it would revert to setting policy under discretion. The escape clause can be expressed as a threshold in terms of a specific variable. The present paper shows that, when such a threshold is expressed in terms of an endogenous variable (e.g. output, inflation), there are cases where it becomes impossible for the central bank to act in a way that is consistent with its promise. Consistency imposes limits on the policy rate that can be set since reverting immediately to the optimal discretionary rate can be incompatible with exceeding the threshold.     

External pressure or internal culture? An innovation diffusion theory account of small retail businesses’ social media use

COVID-19 put unprecedented external pressure on small businesses to adopt or increase use of social media while not all small businesses are internally ready for this rapid change. This study investigated the roles of external pressures and organizational culture of openness and learning in driving small retail business owners'/managers' social media use decisions by impacting their perceived usefulness and barriers, based on the innovation-decision process model from the diffusion of innovations theory and the theory of reasoned action. An online survey with structured measurements was administered to 411 U.S. small retail business owners/managers. Results from structural equation modeling revealed that external pressures positively influenced small business owners'/managers’ perceived usefulness and barriers and social media use intention. In addition, the culture of openness and learning positively influenced the perceived usefulness while mitigating the perceived barriers, thereby directly and indirectly influencing the social media use intention. Theoretical and managerial implications are discussed.     

对群众体育锻炼中，如何合理安排运动量的探讨

本文在体育锻炼能够增强体质，提高健康水平的生物学基础上和群众体育锻炼与专业训练的区别上，提出群众体育锻炼中如何合理安排运动量。     

Stock Price and Volume Effects Associated with Compositional Changes in European Stock Indices

This paper provides further evidence of price and volume effects associated with index compositional changes by analysing the inclusions (exclusions) from the French CAC40 and SBF120 indices, as well as the FTSE100. I find evidence supporting the price pressure hypothesis associated with index fund rebalancing, but weak or no evidence for the imperfect substitution, liquidity and information hypotheses. The results improve on recent evidence from the S&P500 index. The evidence for the FTSE100 additions shows, in particular, that markets learn about an imminent inclusion and incorporate this information into prices, even before the announcement date.     

水压作用下房屋地下室底板开裂的结构处理

地下水压力过大引起房屋地下室底板钢筋混凝土开裂,甚至被破坏,文章介绍采用钻孔桩加固技术进行结构处理,并新作防水层防水。     

Short sales, price pressure, and the stock price response to convertible bond calls

The announcement of a convertible bond call is associated with an average contemporaneous abnormal stock price decline of 1.75% and an ensuing price recovery in the conversion period. A price fall and the subsequent recovery suggest price pressure as the explanation for the announcement effect. However, in general the option to convert is not exercised early and hence, the increase in the number of shares outstanding does not occur at the announcement date. Instead, this paper argues and provides evidence that hedging-induced short selling causes at least part of the short-run price pressure.     

外在压力与内在激励：老龄化背景下地方政府的财政选择

在人口老龄化背景下,地方政府的财政支出选择存在外在压力和内在激励。在理论分析人口老龄化影响地方财政支出偏好的作用机制基础上,采用中国省级财政数据检验老龄化背景下地方财政选择偏好。研究结果表明：地方政府财政支出是提高社会福利支出的外在压力和增强地方财政可持续性的内在激励的多路径效应结果,这种影响效应具有财政自给率和老龄化程度的非对称性。为了实现地方财政可持续性和有效应对老龄化社会的公众诉求压力,有必要尽快完善地方政府考核体系,完善地方公共支出的需求表达机制,改善当前财政支出责任地方化的状态。     

两端铰支二跨梁的临界压力分析

推导出了两端铰支二跨梁的临界压力表达式，具体导出了两跨长度相等情况下的临界压力计算公式，此公式与等长度的单跨梁的欧拉临界压力公式的形式完全相同。     

"泛珠三角"经济圈产业梯度转移研究

生产成本上升,资源瓶颈,腹地狭小已成为“大珠三角”发展的“软肋”,在以上方面,其他8省区相对于“大珠三角”则能优势互补,产业梯度转移成为泛珠三角区域产业发展的迫切要求。根据区域产业梯度转移规律,泛珠三角各省区具备了产业梯度转移的各项条件。在产业转移过程中,应发挥各地区的比较优势,以大珠三角为龙头,通过由港澳——粤闽发达省份——其他欠发达省份级差转移的“雁形发展模式”实施产业转移。另外,在转移中,应注重发挥企业的主体作用和政府的协调作用。     

Threshold models for trended time series

This paper presents the theoretical development of a new threshold autoregressive model based on trended time series. The theoretical arguments underlying the model are outlined and a nonlinear economic model is used to derive the specification of the empirical econometric model. Estimation and testing issues are considered and analysed. Additionally we apply the model to the empirical investigation of U.S. GDP.This paper is the result of work carried out for the author's Ph.D. thesis. I would like to thank Hashem Pesaran for his help, encouragement and insights during the preparation of this paper. I also thank Gary Koop and Sean Holly for helpful comments. Financial assistance from the Economic and Social Research Council is gratefully acknowledged.