Applicability of the Revised Mean Absolute Percentage Errors (MAPE) Approach to Some Popular Normal and Non-normal Independent Time Series

Commonly used Mean Absolute Percentage Errors (MAPE) and the authors’ revised Mean Absolute Percentage Errors (RMAPE) are applied to measure the forecasting accuracy from different Moving Average Methods for independent time series. Simulation results show that both MAPE and RMAPE can only provide sensitive forecasting accuracy measurements on Moving Average Methods when coefficients of variation (c.v.) are smaller than 0.4 or is much greater than 4.0 for those independent time series. For independent time series with moderate c.v.’s, the complexity from the ratios of MAPE and RMAPE will mislead researchers on distinguishing the forecasting accuracies from different Moving Average Methods. The complexity from the ratios will be released only when the c.v. is very small, or when the c.v. is very large. Therefore, when data are from independent time series, the Mean Absolute Deviation (MAD) reveals valid the forecasting accuracies from various Moving Average Methods, but not from MAPE or RMAPE.     

关于材料工程系人才培养模式创新实验区的建设研究报告

宁夏建设职业技术学院材料工程系从市场需求出发,创新人才培养模式,已取得明显成效。     

筒仓钢罩棚室内通风换气的工艺设计

筒仓仓顶钢罩棚作为一种附属设施,在粮食物流方面得到广泛应用,由于粮食自身通风需要,排到室内的热废空气,也应该及时排到室外,本文就该系统自然通风换气的设计进行了有益的探讨。     

Efficiency of the Banking Industry Structure in Korea*

This paper analyzes whether the efficiency of the Korean banking industry has improved since the bank restructuring in 1997, and whether a bank with high efficiency has a larger market share. This paper uses an efficient structure hypothesis model to examine the relationship between the banks' efficiencies and their profitability. The data envelopment analysis method is applied to measure the efficiency and profitability of the banking industry in order to minimize possible bias due to the inflow of public funds for the bank consolidation. The two‐step Heckman selection method is used to correct for survivorship bias in the model. The derived result indicates that banks with higher efficiencies tend to record higher profit. Moreover, higher pure technological efficiency and scale efficiency have a positive effect on a bank's market share and concentration.     

Inflationary Finance, Capital Controls, and Currency Substitution

This paper studies currency substitution in an environment where agents' inflation tax-evasive demand for foreign money is balanced by the concern for the possibility that the government may impose economy-wide capital controls under which foreign currency transactions are costly. Under the assumption of endogenous beliefs, the results show a persistent demand for foreign money despite efforts by the government to reduce inflation. In addition, the economy can exhibit multiple, Pareto-ranked steady states with different levels of currency substitution. The stability analysis suggests that the economy converges to the inferior steady state, on the "wrong side" of the Laffer curve.     

我国出口贸易贫困化增长的现状、原因及对策

＂贫困化增长＂理论是分析国际贸易对发展中国家影响的重要理论,最早由巴格瓦蒂提出。本文对中国出口贸易出现贫困化增长的现状与原因进行了分析,其中贸易增长的动力转换不到位是根本原因。在此基础上,提出了相关对策,如加快产业结构调整、转变出口增长方式,创造良好的外贸体制环境等。     

现阶段我国的市场均衡问题探讨

进入买方市场后,我国一直存在内需不足、经济增长乏力、失业压力日益加大、物价持续下降等一系列经济不景气的现象,政府虽然采取了一系列措施刺激消费需求,但社会经济发展失衡的根本原因--总供给与总需求的不平衡现象一直未能从根本上得到解决。本文主要对我国经济目前市场存在的问题作一探讨并提出相应的思考与看法。     

浅谈大体积混凝土防裂施工技术

文章分析了大体积混凝土裂缝产生的原因,从工程实践中介绍了防止裂缝发生的措施,可在工程实践中提供参考.     

Big Six auditors and audit quality: The Korean evidence

This study investigates the association between discretionary accruals and Big Six and non-Big Six auditors, and the direction of auditor change. We hypothesize that there is no significant difference in discretionary accruals between Big Six and non-Big Six clients when there is low incentive for auditors to provide high-quality audits, as in Korea.Upon examination of the discretionary accruals of firms listed on the Korean Stock Exchange from 1994 to 1998, we find there is no significant difference between the discretionary accruals of firms with Big Six and non-Big Six auditors. This holds true for firms that switch from non-Big Six to Big Six auditors and vice versa. These resources imply that there may be no difference in audit quality between Big Six and non-Big Six auditors in Korea. This is consistent with other studies in Korea, while inconsistent with the findings of previous studies on audit quality in other countries.