“双积分”政策下汽车制造商竞争定价与减排策略研究

"双积分"政策的实施对汽车制造商的定价决策产生了重要影响。考虑卖方由同时生产燃油车和新能源汽车的制造商1和仅生产新能源汽车的制造商2组成,在消费者低碳偏好和价格竞争影响下分别针对制造商1对燃油车采取和不采取节能减排措施的情况,研究"双积分"政策下汽车制造商的定价策略和减排决策,探讨新能源汽车积分值和积分比例要求对政府和企业决策的作用效果。进一步,通过对不同情形的结果进行分析,得到"双积分"政策的出台、消费者低碳偏好及制造商采取节能减排措施对制造商定价和减排决策带来的变化,并通过算例分析验证了结论。研究结果表明:(1)"双积分"政策可以降低新能源汽车的价格,提高新能源汽车制造商的利润,促进燃油车主动减排。(2)当新能源汽车的需求价格弹性系数和需求交叉价格弹性系数处于较高水平时,政府要制定较高的每台新能源汽车积分值。(3)燃油车的油耗水平存在一个环境属性标准,当油耗水平低于一定值时,随着新能源汽车积分比例要求的不断增大,制造商1选择提高燃油车价格。(4)消费者低碳偏好是提高燃油车减排水平的重要因素,政府可以对减排技术先进的燃油车制造商进行低油耗认证,提高消费者低油耗燃油车需求,激励燃油车制...     

Analysis of child labour in Peru and Pakistan: A comparative study

This paper analyses child labour participation and its key determinants using data sets from Peru and Pakistan. The results include tests of the ‘Luxury’ and ‘Substitution’ hypotheses that play key roles in recent studies on child labour and child schooling. The results reject both hypotheses in the context of child labour in Pakistan and suggest that income and related variables do not have the expected negative effect on children's work input. Rising wages of adult female labour in Pakistan, and falling adult male wage in Peru lead to increased participation of children in the labour market. The results on the combined country data formally establish the presence of strong individual country effects in the estimated regressions. For example, ceteris paribus, a Peruvian child is more likely to experience schooling than a Pakistani child. However, both countries agree on the positive role that adult female education and infrastructure investment in basic amenities can play in discouraging child labour and encouraging child schooling. Received: 24 August 1998/Accepted: 10 March 1999     

元大都戏剧艺人略论

元大都辉煌的戏剧文化是杂剧家和戏剧艺人共同创造的。大都的戏剧艺人的演艺水平很高,一大批演员都具有角色行当上的专长。在大都梨园中不乏夫妻或父母子女同为艺人的,由此形成了一些艺人之家或艺人世家,元代戏剧艺人演艺水平之高,与此种现象有内在联系。此外,大都一些戏剧艺人在文学创作上也有令人瞩目的成绩。     

A general central limit theorem and a subsampling variance estimator for α‐mixing point processes

We establish a central limit theorem for multivariate summary statistics of nonstationary α‐mixing spatial point processes and a subsampling estimator of the covariance matrix of such statistics. The central limit theorem is crucial for establishing asymptotic properties of estimators in statistics for spatial point processes. The covariance matrix subsampling estimator is flexible and model free. It is needed, for example, to construct confidence intervals and ellipsoids based on asymptotic normality of estimators. We also provide a simulation study investigating an application of our results to estimating functions.     

《易经》文学化品质的三维结构

《易经》是一部文学化的哲学著作。结构维域下其具有言、象、意等三个层面的成分构成,具有语音的韵律性音乐性、字词含义的精练性多义性、阐义释理的形象性生动性、载道寓理的蕴藉性丰富性等文学品质。对《易经》进行文学化结构成分分析,可以使人感受《易经》与后世文学的契合和交流关系,彰显其文学品质价值。可以拉近《易经》与读者之间的心理距离,使《易经》获得更多的文化观照。但目前相关方面的研究并不系统充分,对此有探讨研究的空间和必要。     

亡宋流人家铉翁的家国情怀

宋元易代之际,家铉翁作为祈请使,被元朝羁縻北方十九年,南归时已年逾八十。今存其创作几乎全作于羁北期间,以抒发故乡之思、故国之念和坚守之志而深切动人,从中体现出深厚的家国情怀。其诗文多以乡国之思蕴涵黍离之悲,以前朝遗民流寓之身,亡国之恨不便于直接表达之故也。     

基于股价预测的泛证券投资组合策略

本文基于期望效用最大化和L₁-中位数估计研究了在线投资组合选择问题。与EG（Exponential Gradient）策略仅利用单期价格信息估计价格趋势不同,本文将利用多期价格信息估计价格趋势,以提高在线策略的性能。首先,基于多期价格数据,利用L₁-中位数估计得到预期价格趋势。然后,通过期望效用最大化,提出一个新的具有线型时间复杂度的在线策略,EGLM（Exponential Gradient via L₁-Median）。并通过相对熵函数定义资产权重向量的距离,进而证明了EGLM策略具有泛证券投资组合性质。最后,利用国内外6个证券市场的历史数据进行实证分析,结果表明相较于UP（Universal Portfolio）策略和EG策略,EGLM策略有更好的竞争性能。     

“无厘头”的影片观看及审美效果的形成

对于“无厘头”影片作为一种文化现象的研究很多,但却少有涉及穿插“无厘头”桥段如何对影片造成影响以及如何形成最终审美效果等观影过程的探讨。自电影符号学之后开始出现影片细读和精神分析取向,而德勒兹哲学则试图对传统的精神分析模式进行改造,将电影的观看视为强度流的物质实践活动。基于此,“无厘头”电影的观看可以看作镜头流与观看的观众身体流的汇合。把镜头流视为叙述文本,通过内在于文本的叙述逻辑（符号意指链的断裂／重组）之间张力的解读,在大量的镜头分析中总结出影片穿插“无厘头”桥段、形成审美效果的规律,并在三阶段的区分中分析张力强度与剧情认同程度关系所造成的影片整体审美效果变动。     

Lurking Behavior in Online Psychosocial Discussion Forums: Theoretical Perspectives and Implications for Practice

Improving outcomes of telebehavioral psychoeducation requires rethinking program design when delivered wholly or partially for self-directed participation. Discussion forum participation often follows the “90-9-1 Rule” where 90% of participants lurk, rather than contribute content. A theoretical perspective on the behavior can help explain its adaptive functions, as well as the threats that this behavior poses to the lurker. Implications for practice require program redesign that actively links individual skills training and group-based discussion. The proposed linking design can synergize individual and group participation to support the development of mutual aid, as well as greater interaction with psychoeducation content and materials.     

青海省入境旅游市场的态势分析及预测研究

随着中国入境旅游的迅速发展,青海省的入境旅游呈现出不同的态势。本文从海外游客客源地、客源国等方面对其进行了深入的分析,在此基础上进行了预测,并提出了可行性建议。