The structure of strategy-proof random social choice functions over product domains and lexicographically separable preferences

We characterize the class of dominant-strategy incentive-compatible (or strategy-proof) random social choice functions in the standard multi-dimensional voting model where voter preferences over the various dimensions (or components) are lexicographically separable. We show that these social choice functions (which we call generalized random dictatorships) are induced by probability distributions on voter sequences of length equal to the number of components. They induce a fixed probability distribution on the product set of voter peaks. The marginal probability distribution over every component is a random dictatorship. Our results generalize the classic random dictatorship result in Gibbard (1977) and the decomposability results for strategy-proof deterministic social choice functions for multi-dimensional models with separable preferences obtained in LeBreton and Sen (1999).     

多空间尺度普通住宅用地的合理地价研究

本文通过房价收入比、地价房价比的关系对住宅市场地价水平的合理值进行估计,用区间分析法来研究普通住宅用地的合理地价区间。考虑到区域差距、行业收入差距大,对国家级、省市级、地区级甚至细化到城市的环线和小区级别,对不同空间尺度下的中等收入家庭年收入等参数进行分析,来估计不同空间尺度下的普通住宅用地的合理地价水平。这有助于建立风险预警系统,引导房地产业向健康稳健方向发展。     

火车票定价与社会福利

一般认为火车票市场之所以存在“倒票”都是因为价格管制的结果。价格管制导致了市场中存在套利机会,但是本文应用一个动态博弈模型论证了:对于火车票这种特殊商品,即使价格升高到供求均衡价格,依然可能存在套利机会;单纯地提高价格不仅不能消除“倒票”行为,而且损害了低收入消费者的福利。本文提出了一种差别定价方式———两期定价方法,可以驱逐市场中的“套利者”;同时,恰当的两期定价还可增进社会福利。     

China and international market integration: Evidence from the law of one price in the Middle East and Africa

We model market integration in the Middle East and Africa by analyzing price dispersion and testing the law of one price (LOP) on highly-comparable actual local retail prices of 135 goods and services across 23 countries in the region over the period of 1990–2016. Second-generation panel estimators are applied to four price benchmarks: Regional average, South Africa, China, and US prices. Cross-regional price dispersion diminishes considerably over time up to 2008, particularly for non-tradeables around China price. The test of LOP indicates the percentage of convergent prices is highest in China price benchmark, followed by US, South Africa, and regional average benchmarks. Direct estimation of the convergence speed confirms this order. Overall, the results show evidence of increasing market integration in Middle East and Africa but it appears to be driven by global forces and, especially, the rise of China as a new economic power. The results show that some emerging market economies, such as China, can step up and promote integration while traditional economic powerhouses, such as the USA and UK, disengage from international economic relations.     

Price gap anomaly in the US stock market: The whole story

This paper analyses the price gap anomaly in the US stock market (comprised of the DJI, S&P 500 and NASDAQ) covering the period 1928 to 2018. This paper aims to investigate whether or not price gaps create market inefficiencies. Price gaps occur when the current day’s opening price is different from the previous day’s closing price due orders placed before the opening of the market. Several hypotheses are tested using various statistical tests (Student’s t-test, ANOVA, Mann-Whitney test), regression analysis, and special methods, that is, the modified cumulative returns and the trading simulation approaches. We find strong evidence in favour of abnormal price movements after price gaps. We observe that during a gap day prices tend to change in the direction of the gap. A trading strategy based on this anomaly was efficient in that its results were not random, indicating that this market was not efficient. The momentum effect was found to be temporary and no evidence of seasonality in price gaps was found. Lastly, our results were also contrary to the myth that price gaps tend to get filled.     

Incentive regulation in local telecommunications: The effects on price markups

The governing bodies of the telecommunications industry instituted a major shift from rate of return to price cap regulation in an effort to foster competition and improve efficiency. This paper focuses on the local exchange market and examines the price markup before and after the implementation of price cap regulation to measure the effects of the change on consumer welfare. The average price markup increased slightly after price cap regulation; however, the average price decreased, indicating that consumers benefited without firms losing from the regulatory shift.      

工程量清单计价与招投标管理

文章介绍和分析了工程量清单招标的优越性,工程量清单计价与招标、工程量清单计价与投标、工程量清单计价与评标的关系,明确指出了工程量清单计价在招投标竞争中能适应市场经济规律的客观要求,通过市场的作用,优化各种相关资源的配置,提高经济效益。     

Logarithmic quasi-homothetic preferences

We study a class of quasi-homothetic preferences, which result in demands that are logarithmic in own prices when these have a negligible impact on aggregate prices (as in monopolistic competition models). Thus marginal revenues are computationally friendly and well behaved.     

招标最低限价与公开保留价对防范串谋的共同作用

本文从防范投标人串谋的角度出发,将招标中的最优公开保留价和最低限价两种方式结合起来,通过一个离散的博弈模型,分析了第二价格密封招标中最低限价和公开保留价在防范串谋中的共同作用,经过研究发现最优公开保留价和最低限价对防范串谋方面所起作用,依赖于投标人的价值分布以及出现的可能性,另外还与投标人进行平行串谋时的成本有关。