Least squares, preliminary test and Stein-type estimation in general vector AR(p) models

In the general vector autoregressive process AR ( p ), multivariate least square estimation (LSE)/maximum likelihood estimation (MLE) of a subset of the parameters is considered when the complementary subset is suspected to be redundant. This may be viewed as a special case of linear constraints of autoregressive parameters. We incorporate this nonsample information in the estimation process and propose preliminary test and Stein-type estimators for the target subset of parameters. Under local alternatives their asymptotic properties are investigated and compared with those of unrestricted and restricted LSE. The dominance picture of the estimators is presented.     

An assessment of value creation in mobile service delivery and the moderating role of time consciousness

This study focuses on the perceived utilitarian value of a new service delivery mode, the mobile channel. The authors develop a framework that incorporates three mode-specific benefits - time convenience, user control, and service compatibility - as well as two costs - perceived risk and cognitive effort - as antecedents of perceived value. Because of the pervasiveness of time criticality as a value-added characteristic of the mobile channel, they also investigate the moderating influence of consumers’ time consciousness. They empirically investigate the model using mobile brokerage services as an illustrative application. The results reveal that the identified antecedents, with the exception of service compatibility, have a strong impact on mobile channel value perceptions, which in turn influence behavioral intentions. The authors also find that time consciousness moderates the aforementioned relationships.     

Local measured telephone service in the USA: A quantitative analysis

The USA has steadfastly held to a flat rate for local telephone service, whereas most other countries are characterized by a user-sensitive (measured service) system of pricing. Economic theory suggests some method of measured service pricing more accurately reflects the true costs of local service. This article seeks to determine how many US consumers could be induced to switch to measured service pricing, and using ordinary least squares, derives a model of the demand for measured service. The factors are identified that will induce the US population to move towards a measured service rate structure. The findings indicate that consumers are quite responsive to both relative price (between a local flat rate and a measured service rate) and advertising.     

Hedonic prices indexes for new passenger cars in Portugal (1997–2001)

This paper evaluates the effects of quality change on the price index for new passenger cars in Portugal for the years 1997–2001. Hedonic regression models are studied, giving particular emphasis to the relation between the form of the price index and the econometric techniques used for inference. The results of the empirical part of the paper indicate that during this period the changes in the quality of new cars sold in Portugal are responsible for price increases averaging 4.8% per year. Because this quality change was not entirely taken into account, in recent years the CPI component corresponding to the sales of new passenger cars may have been overestimated by as much as 2.2 percentage points per year. This corresponds to an overestimation of the overall CPI by about 0.15 percentage points per year.     

On the selection of forecasting models

It is standard in applied work to select forecasting models by ranking candidate models by their prediction mean squared error (PMSE) in simulated out-of-sample (SOOS) forecasts. Alternatively, forecast models may be selected using information criteria (IC). We compare the asymptotic and finite-sample properties of these methods in terms of their ability to mimimize the true out-of-sample PMSE, allowing for possible misspecification of the forecast models under consideration. We show that under suitable conditions the IC method will be consistent for the best approximating model among the candidate models. In contrast, under standard assumptions the SOOS method, whether based on recursive or rolling regressions, will select overparameterized models with positive probability, resulting in excessive finite-sample PMSEs.     

Systematic risk estimation in the presence of large and many outliers

It is well recognized that the effect of extreme points on systematic risk estimates is not adequately captured through least squares estimation. This article uses the reweighted least median squares (RWLMS) approach, first proposed by Rousseeuw (1984), which accurately detects outlier presence. Using a large sample of 1350 NYSE/AMEX firms, the article demonstrates that least squares does indeed mask several potentially influential points, that this masking is very pervasive over the sample, and that it may persist even after conventional robust estimation techniques are applied. When these masked points are “unmasked” by RWLMS and zero weights assigned to such observations, the resulting RWLMS estimates of beta are on average 10%–15% smaller. However, a Bayesian treatment of such points (assigning a priori nonzero weights) is possible in both one and two factor market models.     

Polytomous logistic regression

In this paper a review will be given of some methods available for modelling relationships between categorical response variables and explanatory variables. These methods are all classed under the name polytomous logistic regression (PLR). Models for PLR will be presented and compared; model parameters will be tested and estimated by weighted least squares and by likelihood. Usually, software is needed for computation, and available statistical software is reported.
An industrial problem is solved to some extent as an example to illustrate the use of PLR. The paper is concluded by a discussion on the various PLR-methods and some topics that need a further study are mentioned.     

产权性质视角下的银行业审计质量与经济利益关系研究——基于偏最小二乘法的估计

以中国2001—2010年A股上市商业银行为研究样本,运用偏最小二乘法,检验不同产权性质的商业银行支付给审计师的经济利益与审计质量的关联性。研究发现:相对于非政府控制的上市银行,政府控制的上市银行支付给审计师的经济利益越大,盈余管理幅度越高;在为政府控制银行提供业务的过程中,银行给予审计师的经济利益过高,导致审计师未能有效地抑制银行的盈余管理行为,审计质量受损,而在为非政府控制的上市银行提供业务情形中,审计质量并未随着经济利益的增加而降低。     

一种适用于强脉冲噪声下的对数型恒模盲均衡算法

针对脉冲噪声下恒模算法(Constant Modulus Algorithm,CMA)失败的问题,通过分析脉冲噪声的影响,提出了一种基于最小均方（Least Mean Square,LMS）准则的对数型恒模算法（Logarithmic-type CMA,LT-CMA）。LT-CMA利用对数函数的非线性变换特性自适应地抑制强脉冲噪声对误差函数的影响,并且利用l2-范数进行信号归一化处理以增强算法的稳健性。仿真结果表明,所提出的LT-CMA可以适应于高斯噪声环境和脉冲噪声环境;与经典自适应均衡算法相比,在收敛速度和稳健性两方面上,所提出的LT-CMA都有显著的提升。     

Assessing mainland Chinese tourists' satisfaction with Hong Kong using tourist satisfaction index

The purpose of this study is to test a two‐step tourist satisfaction index framework empirically. The first step estimates sectoral‐level satisfaction indexes based on a structural equation model, and the second obtains an overall tourist satisfaction index by conducting second‐order confirmatory factor analysis. This study is a pilot test of the theoretical framework based on three tourism‐related service sectors in Hong Kong. The results indicate that mainland Chinese tourists are most satisfied with the hotel sector in Hong Kong, followed by the retail sector, and least satisfied with local tour operators. The aggregate tourist satisfaction index is 74.04 out of 100. The results of this study have important practical implications for long‐term destination management. Copyright © 2010 John Wiley & Sons, Ltd.