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81.
Recent non-parametric statistical analysis of high-frequency VIX data (Todorov and Tauchen, 2011) reveals that VIX dynamics is a pure jump semimartingale with infinite jump activity and infinite variation. To our best knowledge, existing models in the literature for pricing and hedging VIX derivatives do not have these features. This paper fills this gap by developing a novel class of parsimonious pure jump models with such features for VIX based on the additive time change technique proposed in Li et al., 2016a, Li et al., 2016b. We time change the 3/2 diffusion by a class of additive subordinators with infinite activity, yielding pure jump Markov semimartingales with infinite activity and infinite variation. These processes have time and state dependent jumps that are mean reverting and are able to capture stylized features of VIX. Our models take the initial term structure of VIX futures as input and are analytically tractable for pricing VIX futures and European options via eigenfunction expansions. Through calibration exercises, we show that our model is able to achieve excellent fit for the VIX implied volatility surface which typically exhibits very steep skews. Comparison to two other models in terms of calibration reveals that our model performs better both in-sample and out-of-sample. We explain the ability of our model to fit the volatility surface by evaluating the matching of moments implied from market VIX option prices. To hedge VIX options, we develop a dynamic strategy which minimizes instantaneous jump risk at each rebalancing time while controlling transaction cost. Its effectiveness is demonstrated through a simulation study on hedging Bermudan style VIX options.  相似文献   
82.
In this article we use an autoregressive fractionally integrated moving average approach to measure the degree of fractional integration of aggregate world CO2 emissions and its five components – coal, oil, gas, cement, and gas flaring. We find that all variables are stationary and mean reverting, but exhibit long-term memory. Our results suggest that both coal and oil combustion emissions have the weakest degree of long-range dependence, while emissions from gas and gas flaring have the strongest. With evidence of long memory, we conclude that transitory policy shocks are likely to have long-lasting effects, but not permanent effects. Accordingly, permanent effects on CO2 emissions require a more permanent policy stance. In this context, if one were to rely only on testing for stationarity and non-stationarity, one would likely conclude in favour of non-stationarity, and therefore that even transitory policy shocks have permanent effects. Our fractional-integration analysis highlights that this is not the case.  相似文献   
83.
由于长期以来我国国土及地矿行业所采用GIS软件主要是MapGIS 6.x,为了面向其他领域提供GIS空间数据共享,需要将大量MapGIS格式数据向ArcGIS格式数据转换。通过对MapGIS与ArcGIS两种数据格式的分析,提出了基于Map2Shp的转换方式。通过这种转换方式可以完整的保存MapGIS数据中的地理信息、属性以及要素特征。再通过匹配两种数据的颜色库和符号库,经过在ArcGIS中的渲染,从而实现从MapGIS到ArcGIS完整的制图表达。  相似文献   
84.
This paper offers new insights into Beveridge curve analysis by modelling the unemployment–vacancy rate relationship within a Markov regime‐switching environment in which the probabilities of curve‐shifting are determined endogenously by shift factors. Shift factors include structural factors such as labour market participation and net migration, while cyclical variables include GDP growth, the real rate of interest, and labour productivity. This approach enables us to estimate regime‐specific parameters and to assess the role played by these factors in influencing the transition probabilities of switching between regimes. Using New Zealand data, we show that increases in the participation rate have shifted the Beveridge curve inward, while increases in net migration have shifted the curve outward.  相似文献   
85.
This research shows for the first time that the level of education has a causal, negative effect on the minimum wage. I use 2SLS, with historical educational data as an instrument for the level of education in 2010, and I find that across the US states a one percentage point greater proportion of college graduates is associated with a real minimum wage that is lower by 1.5%–1.6%. Also, in order to control for state-level omitted variables, I regress the change in the minimum wage on the change in education and I find again a negative, and significantly at the 1% level, effect. Minimum wage is a policy that is chosen by governments according to voters’ preferences. The results of this research imply that when the level of education increases voters prefer a lower minimum wage.  相似文献   
86.
《商》2016,(9)
网络信贷起源于英国,2007年引入到中国,模式从最初的资产抵押到纯信用借贷,人群从普通工薪阶层覆盖到在校大学生,形式从最初的现金业务拓展到购物消费分期。行业背后的投资来源也逐步广泛随着网贷的不断发展,诸多问题相继产生,值得我们深入探讨。  相似文献   
87.
伴随着新媒体的发展,“中国大妈”和与其结构类似的“中国式X”的网络流行语正在受到越来越多的关注。代表一种独特的文化现象的“中国式X”,本身就是一个语言模因,它的各种次生语言形式在模因的作用下得以在社会大众之间广泛繁殖和衍生。我们既可以从认知语言学的概念重叠和概念整合角度对“中国大妈”的形成及其所隐含的调侃语义进行解读,也可以从社会文化学领域的模因论视角对“中国式X”的传播进行探讨。  相似文献   
88.
The experience curve is a tool for forecasting future decreases in average cost as a function of cumulative output/volume. The extent of an experience effect has profound implications for both pricing strategy and the focus on market share as a managerial objective. At the same time, the underlying sources of the experience effect are not well understood. This article demonstrates that, as commonly measured, experience effects are aggregated with the effects of increasing returns to scale. This implies that standard experience curve estimates are misspecified because they suffer from an omitted variable bias. Strategic implications of the experience‐scale link are discussed.  相似文献   
89.
近年来,随着我国经济不断的增长,广义货币供应量也在逐年的攀上新的高峰,今年的三月份更是突破了100万亿的大关,那么研究广义货币供应量与经济发展之间的相互关系也就变得很重要。选取1998年1月份至2012年3月份中国广义货币供应量和GDP的月度数据作为样本数据,通过建立VAR模型,运用协整检验、脉冲响应函数和方差分解等分析方法,对M2对于GDP发展的影响进行分析。  相似文献   
90.
文章利用2014年天津市武清区大气污染物臭氧(O_3)、二氧化氮(NO_2)和一氧化碳(CO)的监测数据,分析研究武清区O_3及其前体物NO_2和CO等大气污染物浓度水平和变化特征。结果表明武清区O_3浓度水平呈现明显的季节变化特征。夏季O_3浓度为106μg·m~(-3),冬季浓度为28μg·m~(-3),主要与光化学反应在夏季比较强烈,冬季紫外强度和平均温度均较低,光化学反应较弱有关。2014年武清区大气中NO_2年均值为51μg·m~(-3),CO年均值为1.9 mg·m~(-3),冬季是NO_2和CO浓度最高的季节。  相似文献   
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