An analysis of stock market transactions data

Many studies have argued against the strict form of the efficient markets hypothesis (EMH) by concluding that a lagged relationship exists between volume and the absolute value of a price change. These studies have denied a priori the possibility of a contemporaneous relationship. If a simultaneous relationship exists then least squares with only lagged variables suffers from omitted variable bias, and least squares with contemporaneous variables may suffer from simultaneous equations bias. Investigating these possibilities, this study demonstrates that simultaneity exists and that previous findings of a lagged relationship between the variables are therefore due to specification error. System estimation techniques suggest that the price-volume relationship is recursive, with the absolute value of a price change causing volume contemporaneously, but not conversely.     

The sociology of a market analysis tool: How industry analysts sort vendors and organize markets

The information technology (IT) marketplace appears to be shaped by new kinds of specialist industry analysts that link technology supply and use through offering a commodified form of knowledge and advice. We focus on the work of one such organisation, the Gartner Group, and with how it produces a market analysis tool called the ‘Magic Quadrant’. Widely circulated amongst the IT community, the device compares and sorts vendors according to a number of more or less intangible properties (such as vendor ‘competence’ and ‘vision’). Given that potential adopters of IT systems are drawn to assess the reputation and likely behaviour of vendors, these tools play an important role in mediating choice during procurement. Our interest is in understanding how such objects are constructed as well as how they wield influence. We draw on the recent ‘performativity’ debate in Economic Sociology and the Sociology of Finance to show how Magic Quadrants are not simply describing but reshaping aspects of the IT arena. Importantly, in sketching this sociology of a market analysis tool, we also attend to the contested nature of the Magic Quadrant. Whilst Gartner attempt to establish this device as an ‘impartial’ and ‘legitimate’ arbiter of vendor performance, it is often viewed sceptically on the grounds that industry analysts are not always independent of the vendors they are assessing. Paradoxically these devices remain influential despite these sceptical assessments.     

Methodological sectarianism in urban sociology

Book reviewed in this article: Becquart-Leclercq, Jeanne , 1976: Paradoxes du pouvoir local. Paris: Presse de la fondation nationale des sciences politiques, 115 francs (cloth) and 80 francs (paper). Biarez, S., Bouchet, C., de Boisberranger, G., Mingasson, C., Monzies, M-C . and Pouyet, C. , 1973: Institution communale et pouvoir politique. Paris: Mouton, 28 francs.     

Evidence of ethnic discrimination in the Swedish labor market using experimental data

We present evidence of ethnic discrimination in the recruitment process by sending fictitious applications to real job openings. Applications with identical skills were randomly assigned Middle Eastern- or Swedish-sounding names and applications with a Swedish name receive fifty percent more callbacks for an interview.We extend previous analyses by adding register and interview information on firms/recruiters to the experimental data. We find that male recruiters and workplaces with fewer than twenty employees less often call applications with a Middle Eastern name for an interview.     

Explaining differences in labour market transitions between panel and life-course data in West-Germany

Panel and life-course data are ideally suited to unravelling labour market dynamics, but their designs differ, with potential consequences for the estimated relationships. To gauge the extent to which these two data designs produce dissimilar transition rates and the causation thereof, we use the German Life History Study and the German Socio-Economic Panel. Life-course data in particular suffer from recall effects due to memory bias causing understated transition probabilities. Panel data suffer from seam effects due to spurious transitions between statuses recalled in activity calendars that generate heaps at particular time points and cause overstated transition probabilities. We combine the two datasets and estimate multilevel (multistate) discrete-time models for event history data to model transitions between labour market states taking these factors into account. Though we find much lower transition rates in the life-course study, confirming the results of Solga (Qual Quant 35:291–309, 2001) in this Journal for East-Germany, part of the difference can be explained by short spells recall bias. The estimated models on exit, re-entry and job mobility on the combined datasets show indeed a negative retrospective design effect. Another specification that includes the length of the recall period shows no significant decrease in the transition probabilities with increasing length, suggesting that the negative design effect is due to other design differences.     

Attrition in longitudinal panel data and the empirical analysis of dynamic labour market behaviour

In the empirical analysis of unemployment durations and job durations, it is generally assumed that the stochastic processes underlying labour market behaviour and the behaviour concerning participation in a panel survey are independent. However, there are reasons to believe that the probability of dropping out of the panel is related to the rate at which a (different) job is found. If there is such a relation, and if it is ignored, then the estimator of the rate at which individuals become employed or change jobs will generally be inconsistent. In this paper we analyse the relation between the duration spent in a particular labour market state and the duration of panel survey participation, by explicitly modelling and estimating the joint distribution of both durations. The emphasis will be on models allowing for stochastically related unobserved determinants of both types of duration. We estimate models both for unemployment durations and for job durations.     

基于数据挖掘技术的股票市场预测分析实例研究

本文主要研究数据挖掘技术在股票市场价格预测中的应用,重点采用数据挖掘分类和聚类算法对大盘走势和个股走势进行分析研究,采用实体数据进行挖掘分析,总结得出有益于投资者的结论。     

城市道路交通环境的社会学分析

在分析城市道路交通环境的内涵、功能和社会属性的基础上,对中国城市道路交通环境现状进行反思与检讨.以社会学视角从可达性权利、愉悦性、社会发展的可持续性三个方面分析了道路交通环境问题.     

Developed stock market reaction to political change: a panel data analysis

This paper utilized panel data to examine the effects of political change in developed stock market. According to Hausman test, we capture the stock return by the fixed-effect model to fit the stock market. Political change was originally intended as an incumbent party impetus to create opportunities for progress. However, this has caused great political party distress, creating political change with an inverse stock return relationship in developed countries.     

Some simple structure significance tests for exploratory component analysis with market survey data

Several uncertainties continue to hinder researchers using exploratory factor analysis. Among other decisions, the choice of the number of factors to retain and the interpretability of the rotated solution remain problematical. In this paper, we suggest a simple structure criterion as a general framework for choosing the number of factors and for interpreting the rotated factor structure matrix. The proposed methodology is demonstrated with demographic data from a consumer panel. The results show the importance of increasing the information yield from exploratory factor analysis.     

普通混凝土配合比设计及试配

针对预拌混凝土企业确定混凝土配比时“重设计、轻试配”的现状,结合配合比设计的条件要素,从混凝土配合比设计、试配、调整三个方面,系统阐述预拌混凝土配合比设计的全过程,突出强调了试配的重要性,进一步明确预拌混凝土配合比设计是在经验、理论指导下的实践性过程。     

Economic fluctuations,market power,and returns to scale: Evidence from firm-level data

Recent research on aggregate fluctuations, coupled with ongoing work in industrial organization, has renewed interest in the existence, magnitude, and cyclical pattern of market power and the extent of increasing returns to scale. By exploiting restrictions from dynamic theory and information from financial markets, we present a framework for generating quantitative evidence on market power and returns to scale. Tailoring the econometric model to firm-level panel data, we calculate the percentage differential between price and marginal cost (the Lerner index) in terms of the parameters from the econometric system. Results for firms in eleven industries indicate that there is a great deal of heterogeneity in the extent of market power. Industries with significantly positive Lerner indices tend to have substantial increasing returns in the production technology. We find that there is only a modest relation between our estimated Lerner indices and traditional measures of market power and that, when market power varies temporally, it is usually procyclical. Thus, variations in the markup of price over marginal cost may help dampen aggregate economic fluctuations.     

Comprehensive analysis of market conditions in the foreign exchange market

We investigate quotation and transaction activities in the foreign exchange market for every week during the period of June 2007 to December 2010. A scaling relationship between the mean values of number of quotations (or number of transactions) for various currency pairs and the corresponding standard deviations holds for a majority of the weeks. However, the scaling breaks in some time intervals, which is related to the emergence of market shocks. There is a monotonous relationship between values of scaling indices and global averages of currency pair cross-correlations when both quantities are observed for various window lengths ?? t.     

北海楼市印象

去北海之前,只是对那里有个笼统的印象。到了才发现,与想像中的三面环海,蓝天、碧海、沙滩、阳光……人居的天堂还是有一定差距。北海当地有句谚语可以很好地表现北方人对北海的无知:北方人好大胆,出门竟敢不带伞。     

新加坡零售市场采风

在新加坡这个商业社会中,生意人将顾客视为"财神爷",对顾客不敢有丝毫怠慢.如果你逛商店,售货员老远就会笑脸相迎,围着你身边介绍一样又一样的商品,殷勤至极,不买点东西真不好意思.