An Empirical Analysis of the Bias and Rationality of Profit Forecasts Published in New Issue Prospectuses

Our study sets out to assess the accuracy of profit forecasts made by IPOs in Hong Kong. We use a variety of measures and tests to examine the accuracy, bias, rationality, and superiority of earnings estimates. The results show that forecast accuracy compares favourably with the findings from the developed economies of Australia, Britain, Canada, and New Zealand. Forecasts are shown to be superior to the predictions from time series models. IPOs tend to underforecast in the sense that actual profits exceed the forecasts. The rationality tests show mixed results. Cross-sectional analyses of forecast accuracy have poor explanatory power although the Big Six reporting accountants are associated with smaller forecast errors.     

Using Leading Indicators to Forecast U.S. Home Sales in a Bayesian Vector Autoregressive Framework

This article uses Bayesian vector autoregressive models to examine the usefulness of leading indicators in predicting U.S. home sales. The benchmark Bayesian model includes home sales, price of homes, mortgage rate, real personal disposable income, and unemployment rate. We evaluate the forecasting performance of six alternative leading indicators by adding each, in turn, to the benchmark model. Out-of-sample forecast performance over three periods shows that the model that includes building permits authorized consistently produces the most accurate forecasts. Thus, the intention to build in the future provides good information with which to predict U.S. home sales. Another finding suggests that leading indicators with longer leads outperform the short-leading indicators.     

日本二元经济转换时期的产业结构变化与相关政策分析

根据刘易斯以及费景汉.拉尼斯的二元经济的理论,可以判定日本经济在上世纪中叶,以日本的产业结构为主导发生了巨大变化,显现出二元经济结构转换的特征。政府为了引导日本经济发展以及顺利度过转折时期采取了一系列的有效政策。这些变化和政策,对面临二元经济转换时期的我国经济提供了重要的参考经验。     

Does foreign investor demand for information affect forecast accuracy? Evidence from the Chinese stock markets

Prior international accounting studies have examined mainly the supply side of analyst research. Specific trading rights and financial reporting systems in China provide a unique opportunity to test both demand and supply factors of analyst information. For shares traded only by less-informed foreign investors, the increased information demand may create incentives for analysts to exert greater efforts than for shares traded by local investors. This study provides evidence that analyst effort (proxied by analyst coverage) and expertise (proxied by consensus cross-analyst forecast variability) affect forecast accuracy more significantly for shares traded by foreign investors than for shares traded by local investors. Additionally, I find that the relation between analyst characteristics and relative forecast accuracy is stronger for shares traded by the foreign investors. The findings are consistent with analysts responding to demands for information by less-informed investors.     

提高电磁流量计测量准确度的方法

针对在注水中电磁流量计测量准确度普遍低于理论值的现状，试验小组根据电磁流量计原理与实际应用工况条件，查找影响电磁流量计测量准确度的主要因素，并制定对策措施进行反复比较实验和效果检查，最终通过5项有效措施的实施，完成电磁流量计测量准确度达到并超过理论值的目标。     

质量流量计在原油集输系统中的应用

对油田企业分区块计量问题的现状进行了分析,指出了目前存在计量误差的主要原因,针对费希尔Ex8300质量流量计在使用中存在的缺陷,重新引进了新型CMF纯油质量流量计,报告了在多个原油集输站的试验情况,通过试验比对,找出了产生系统误差的根本原因,提出了在分队、分区块计量中质量流量计的应用是可行的,并告戒仪表管理人员对质量流量计的输入参数的动态变化要进行适时调整,以保证仪表的计量准确。     

Comparing the accuracy of several network-based COVID-19 prediction algorithms

Researchers from various scientific disciplines have attempted to forecast the spread of coronavirus disease 2019 (COVID-19). The proposed epidemic prediction methods range from basic curve fitting methods and traffic interaction models to machine-learning approaches. If we combine all these approaches, we obtain the Network Inference-based Prediction Algorithm (NIPA). In this paper, we analyse a diverse set of COVID-19 forecast algorithms, including several modifications of NIPA. Among the algorithms that we evaluated, the original NIPA performed best at forecasting the spread of COVID-19 in Hubei, China and in the Netherlands. In particular, we show that network-based forecasting is superior to any other forecasting algorithm.     

三基地雷达最佳空间定位算法

将三基地雷达二维定位最佳算法加以推广,在不增加设备量的前提下,充分利用各雷达站的测量信息,对三基地雷达三维空间直线布站的最佳算法进行推导和研究.仿真结果显示,空间相关数据压缩算法比独立数据压缩算法更加有效地提高了目标定位精度,特别是较好地改善了发射站附近区域的定位性能,有效解决了双基地雷达空间定位的基线盲区问题.     

微波带状线低通滤波器的设计制作与性能改善

讨论了带状线低通滤波器因实际制作的导带宽度发生变化引起滤波器性能下降时，如何改善滤波器性能的方法。我们采用惠普公司ＥＥＳＯＦ软件，对滤波器的结构和电气参数和分别作了灵敏度分析，以此为改善滤波器性能的依据。经实验对比，改进后的滤波器性能有了明显改善，且性能稳定。     

关于机器人姿态偏差描述方法的讨论

本文针对国际标准草案 ISO/DP9283中用欧拉角的偏差描述机器人姿态偏差的规定,作者认为三个欧拉角的偏差没有独立的物理意义,不反映机器人姿态偏差的大小,这种描述方法十分不妥;主张以一次转动的转角描述机器人的姿态偏差。