THE IMPACT OF POINT‐OF‐SALE DATA INACCURACY AND INVENTORY RECORD DATA ERRORS

The presence or absence of error in point‐of‐sale (POS) data and inventory system records directly affects retailer performance. This study identifies various error sources in retail supply chains and studies the influence of inventory and POS (demand) errors in a simulated retail outlet according to fill rate and average inventory. Other things being equal, we find that inventory record error reduces fill rate more than demand error. This study adds further evidence to other studies that suggest the costs caused by errors in POS systems may be overstated.     

On the discrepancy in the social efficiency measures between parametric and non-parametric production technology identification

In conventional social productive efficiency measurements that consider the production of undesirable outputs such as CO2, a DEA-based non-parametric method of production possibility frontier (PPF) identification coupled with the directional distance-function approach a-la Luenberger (1992) is typically employed. This paper shows that the discrepancy between parametric and non-parametric methods of PPF identification in social inefficiency measures can be non-negligibly large when the number of observations is small or the data are not well-scattered. By using the same data as Ha et al. (2011), who used non-parametric PPF identification to measure the social efficiency of Japan's inter-city transport services with lifecycle CO2 as the undesirable output, this paper demonstrates that adopting parametric PPF identification instead can result in considerably higher inefficiency measures for decision making units (DMUs) with relatively large undesirable outputs.     

Does the financial analysts' usage of non-financial information influence the analysts' forecast accuracy? Some evidence from the Belgian sell-side financial analyst

This paper examines whether the use of non-financial information by sell-side financial analysts influences the accuracy of analysts’ forecasts. The research findings, based on a survey of Belgian financial analysts, suggest that financial analysts who use more forward-looking information and more internal-structure information offer more accurate forecasts. Furthermore, the listed Belgian firms examined in this study have improved their non-financial information reporting over time. However, neither the frequency nor the quantity of non-financial information mentioned by financial analysts in their reports appears to have increased over time.     

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.     

Performance of French intensive care units: A directional distance function approach at the patient level

By using a novel adaptation of the free-disposable hull analysis of productivity, we assess the medical and technical efficiency of patient care in 25 Parisian intensive care units (ICUs) during 2000. The robust free disposable hull (RFDH) as defined by [Cazals et al., 2002. Nonparametric frontier estimation: a robust approach. Journal of Econometrics 106, 1–25] reduces the impact outliers may have on findings by employing Monte-Carlo techniques and repeated sample selection. Among our key findings, there was no overall significant correlation between medical and technical efficiencies for all the ICUs, therefore performing well in one does not guarantee good performance in the other. We also found that over 80% of inefficiency is concentrated in less than 20% of the sampled patients.     

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。     

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.     

提高关口电能计量装置准确度技术分析

随着电力体制的改革和电力工业的发展,发电企业用于结算电量的电能表由发电机前移至主变出口最终前移至线路出口关口电能表,就要求关口电能计量装置的准确度愈来愈高。本文针对大唐珲春发电厂220千伏系统二期关口电能计量装置误差产生的原因进行分析,发现影响关口电能表准确度的各项因素,制定解决方案逐步进行实施,消除这些不利因素对关口电能表的影响,提高关口电能计量装置准确度,希望能起到借鉴作用。     

Are analysts' cash flow forecasts useful?

This study provides evidence that the cost of equity capital decreases with the number of analysts who issue both cash flow and earnings forecasts (cash analysts). The evidence also shows that cash analysts reduce information asymmetry and predict long‐term earnings more accurately than analysts who issue only earnings forecasts. Taken together, these findings suggest that cash analysts provide market participants with high‐quality information and, as a result, firms benefit from cash analyst coverage in the form of a reduced cost of equity capital.     

测控通信系统射频资源可重组技术

测控通信系统的资源重组将是飞行器测控通信系统的发展方向。在中频实现测控终端重组的基础上,通过对射频重组构架的分析,得出了射频交换网络的性能和射频远距离传输的性能直接影响射频重组的可行性,提出了一种可行的全系统资源重组的测控体系构架,即采用微光电子射频交换网络与射频光波传输技术实现射频信号大规模交换及远距离传输,再结合中频重组以实现全系统资源重组,并对相关性能进行了分析。所提出的设计思路可供测控通信系统实现全体系的资源重组借鉴及参考。