News and intraday jumps: Evidence from regularization and class imbalance

We study how information provokes intraday price jumps taking into account, besides news timing, the sentiment of news stories and other high-frequency indicators. By applying penalized logistic regression and addressing the rare nature of jumps, in addition to the previous evidence showing that causes of jumps are rate decisions and earnings announcements, we find that news provoking jumps is often followed by other news about the same company, that news stories sentiment and macro-surprises sign help to predict the jump sign, and, finally, that market players sometimes anticipate company-specific news.     

城市创新能否助力低碳经济发展——创新型城市试点政策对碳强度的影响评估及机制分析

创新是城市发展的力量之源，低碳是城市发展的必由之路。将创新型城市试点作为一项准自然实验，利用2005—2018年全国275个城市面板数据，采用多期双重差分方法，评估创新型城市试点对降低碳强度的政策效应及作用机制。研究发现：第一，创新型城市试点政策能够在降低碳强度的基础上推动低碳经济发展，各类试点政策的推动效果依次为碳排放权交易政策>创新型城市政策>智慧城市政策>低碳城市政策>环境保护重点监控政策；第二，创新型城市试点政策可以通过规模经济效应、技术进步效应与结构转型效应3条路径助力低碳经济发展；第三，城市特质会影响创新型城市试点政策效应发挥，创新型城市试点政策对碳强度的抑制效果呈现由东到西递增的地理空间差序格局、由高到低递减的城市等级差序格局，在人口规模与抑制效果之间呈现倒U型作用，并且资源型城市的抑制效果显著大于非资源型城市。