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31.
This study investigates the relationship between internal pyramid structure and performance of Chinese, Pakistani, Malaysian pyramidal firms, the effect of judicial efficiency and minority investor protection on this relationship. The results show that the pyramid structure of Pakistani firms is more complicated than Chinese and Malaysian firms, both vertically and horizontally. The study finds that the impact of control layers on performance is negative and stronger than control chains. Moreover, the results illustrate that the effect of control layers on performance at Chinese firms is negative but lower than at Pakistani and Malaysian firms. However, control chains have insignificant association with performance at Chinese pyramid firms. We find that efficient judiciary abates the negative impact of control layers and chains on performance. Our results reveal that in the absence of efficient courts the minority investors’ protection have insignificant impact on the association between internal pyramid structure and firms’ performance.  相似文献   
32.
Exploiting a regulatory change in short-sale constraints (Regulation SHO) as a natural experiment, this paper examines the effect of short-sale constraints on informational efficiency of stock prices to private information. I find that short-sellers act as informed traders prior to forthcoming analyst news and trade on negative private information. When short-sale constraints are relaxed for pilot stocks (treatment group), both trading volume and stock price sensitivity increase prior to the analyst announcement for bad news but not for good news, relative to that of nonpilot stocks (control group). The findings are consistent with the Diamond and Verrecchia model that predicts that short-selling increases the speed of adjustment of stock prices to private negative information. In the cross-section, the effect of Reg SHO is stronger in stocks of firms with weak and uncertain information environments (i.e., small firms and firms with high analyst forecast dispersion).  相似文献   
33.
This paper proposes energy consumption in the US as a new measure for the consumption capital asset pricing model. We find that (i) industrial energy growth produces reasonable values for the relative risk aversion coefficient and the implied risk-free rate; (ii) compared to alternative consumption measures, industrial energy performs well in explaining the cross-sectional variation in stock returns with the lowest implied risk aversion and pricing errors; (iii) the industrial energy consumption risk model performs equally well as the Fama–French three-factor model in the cross-sectional asset pricing tests; and (iv) total energy consumption risk is priced in the presence of the Fama–French factor risks.  相似文献   
34.
We construct a measure of the speed with which forecasts issued by sell-side analysts accurately forecast future annual earnings. Following Marshall, we label this measure earnings information flow timeliness (EIFT). This measure avoids the aggregation problem inherent in price-based measures of information efficiency. We document large variation in EIFT across firm-years, and show that EIFT is positively associated with the extent of analyst following, consistent with increased analyst coverage improving the speed with which earnings-related information is recognised. We also find that EIFT is higher for firm-years classified as ‘bad news’ (i.e., where analysts’ forecasts at the start of the financial period exceed the reported outcome). However, when we separately consider instances where analysts appear to forecast non-GAAP (or ‘street’) earnings rather than GAAP earnings, we find that the greater timeliness of bad news is concentrated among observations where analysts forecast non-GAAP earnings, where unusual items are typically excluded. We conclude that the market for accounting information is more efficient for negative operating outcomes than for negative outcomes reflecting unusual items.  相似文献   
35.
We propose a dynamic factor state–space model for high-dimensional covariance matrices of asset returns. It makes use of observed risk factors and assumes that the latent integrated joint covariance matrix of the assets and the factors is observed through their realized covariance matrix with a Wishart measurement density. For the latent integrated covariance matrix of the assets we impose a strict factor structure allowing for dynamic variation in the covariance matrices of the factors and the residual components as well as in the factor loadings. This factor structure translates into a factorization of the Wishart measurement density which facilitates statistical inference based on simple Bayesian MCMC procedures making the approach scalable w.r.t. the number of assets. An empirical application to realized covariance matrices for 60 NYSE traded stocks using the Fama–French factors and sector-specific factors represented by Exchange Traded Funds (ETFs) shows that the model performs very well in- and out of sample.  相似文献   
36.
Food waste has drawn increasing public attention, and the high levels of estimated waste are largely considered to be a failure of our current food system. Recently, economists have begun to weigh in, showing food waste can emerge as the result of a complex equilibrium affected by consumers’ preferences for convenience; expectations about future food prices and availability; food safety concerns; producers’ costs of holding inventory, transportation, and storage; government regulation; and technology. If food waste is a form of inefficiency, there are either strong economic motivations to reduce waste, or unmeasured costs or preferences affecting waste decisions. If consumers have behavioral biases, suffer from information asymmetries, or do not pay the full cost of their waste, there may be a role for government intervention to reduce waste, but most empirical models in the literature have not articulated or quantified the extent of the deadweight loss from the market failures in relation to food waste. In some cases, waste reduction efforts could harm producers if overall demand for food is reduced or harm consumers if overconsumption is encouraged, quality or safety degrades, or supply disruptions occur. Technological innovations, which lower the cost of storage or extend shelf life have the potential to improve both consumer and producer welfare.  相似文献   
37.
考虑非期望产出,基于企业层面,根据2011-2016年数据,采用DEA-SBM模型与DEA-CCR模型对中国12家地板上市公司的环境效率与经济效率进行测算与比较。结果表明:2016年环境效率和经济效率测算结果显示不同地板上市企业运行效率存在差别;与经济效率相比,一些企业如北新建材、扬子地板,环境效率保持不变,一些企业如宜华生活、吉林森工和丰林集团,环境效率得到提升;还有一些企业如兔宝宝、升达林业和大自然家居等,环境效率则出现下降。考虑了非期望产出,中国地板上市企业整体环境效率均值低于经济效率均值,总体处于0.79~0.84之间。提出了政府应加强监管力度,地板上市企业应提高技术改进能力,建立完善社会责任信息披露机制的建议。  相似文献   
38.
This paper investigates the portfolio optimization under investor’s sentiment states of Hidden Markov model and over a different time horizon during the period 2004–2016. To compare the efficient portfolios of the Islamic and the conventional stock indexes, we have employed two approaches: the Bayesian and Markowitz mean-variance. Our findings reveal that the Bayesian efficient frontier of Islamic and conventional stock portfolios is affected by the investor’s sentiment state and the time horizon. Our findings also indicate that the investor’s sentiment regimes change the Islamic and the conventional optimal diversified portfolios.Moreover, the results show that the potential diversification benefits seem to be more important when using the Bayesian approach than when applying the Markowitz approach. This finding is valid for the bearish, depressed, bullish and calm states in Islamic stock markets. However, the diversification of potential portfolios is significant only for the bullish and the bubble states in the conventional financial markets.The findings of the study provided additional evidence for investors to exploit googling investor sentiment states to evaluate the portfolio performance and make an optimal portfolio allocation.  相似文献   
39.
The aim of this article is to obtain a statistical distribution that describes the aggregate expenditure of tourists related to their length of stay at a given location. This distribution enables us to estimate two parameters simultaneously; one controls the length of stay and the other, the expense incurred. We propose two distribution models, for which closed-form expressions are obtained. Covariates are introduced in order to study the factors that affect the aggregate expenditure. The results obtained indicate that the models achieve a reasonably good fit, with and without covariates.  相似文献   
40.
Replacing conventional vehicle taxis with electric vehicles would be an efficient measure to reduce greenhouse gas emissions. Due to the limited range and long charging times of current battery electric vehicles, it is of utmost importance to provide sufficient charging facilities. This article analyses the impact of the placement and charging power of charging stations on potential mileage and revenue of electric taxis on the example of Singapore. Therefore, we developed an agent-based electric taxi simulation model to investigate electric taxis’ driving profiles with respect to different vehicle types and charging infrastructure designs. This model is also capable of simulating conventional taxi driving profiles. The validation of these simulation results with real taxi data showed that the model is reproducing taxi driving profiles with high accuracy in great detail. We found out that electric taxis could reach the same mileage and revenue as conventional taxis if charging with a power of 160?kW is possible. Furthermore, we discovered that waiting times for available charging stations have a stronger effect on revenue than the length of detours to reach charging stations. Based on these findings, we concluded that it is more important to reduce waiting times by placing sufficient numbers of charging stations at each location before expanding the charging network by installing small numbers of charging stations at many locations.  相似文献   
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