Performance assessment and improvement of control charts for statistical batch process monitoring

This paper describes the concepts of statistical batch process monitoring and the associated problems. It starts with an introduction to process monitoring in general which is then extended to batch process monitoring. The performance of control charts for batch process monitoring is discussed by means of two performance indices: the overall type I error and the action signal time. Problems associated with the existing approach are discussed and highlighted. Improvements are suggested and checked with the performance indices. To evaluate the effect of the proposed improvements as well as to assess the performance of the existing approach, an industrial batch production process is used.     

Do Government Subsidies Stimulate Training Expenditure? Microeconometric Evidence from Plant-Level Data

This paper examines whether financial assistance provided by government induces firms to spend more of their own funds on training expenditures, using plant-level data for the Republic of Ireland. We pay particular attention to the potential problems in such an evaluation study, namely selectivity and endogeneity, by first identifying a valid counterfactual for grant receiving plants via a matching estimator and then employing a difference-in-differences technique on this matched sample. Our results show that there are differences in causal effects between domestic and foreign-owned plants. For the former, we find clear evidence that grant receipt stimulates private expenditure, whereas there are no statistically significant effects for foreign-owned plants based in Ireland.     

Demographic Issues in Longevity Risk Analysis

Fundamental to the modeling of longevity risk is the specification of the assumptions used in demographic forecasting models that are designed to project past experience into future years, with or without modifications based on expert opinion about influential factors not represented in the historical data. Stochastic forecasts are required to explicitly quantify the uncertainty of forecasted cohort survival functions, including uncertainty due to process variance, parameter errors, and model misspecification errors. Current applications typically ignore the latter two sources although the potential impact of model misspecification errors is substantial. Such errors arise from a lack of understanding of the nature and causes of historical changes in longevity and the implications of these factors for the future. This article reviews the literature on the nature and causes of historical changes in longevity and recent efforts at deterministic and stochastic forecasting based on these data. The review reveals that plausible alternative sets of forecasting assumptions have been derived from the same sets of historical data, implying that further methodological development will be needed to integrate the various assumptions into a single coherent forecasting model. Illustrative calculations based on existing forecasts indicate that the ranges of uncertainty for older cohorts' survival functions will be at a manageable level. Uncertainty ranges for younger cohorts will be larger and the need for greater precision will likely motivate further model development.     

Optimal Portfolio Allocation under Higher Moments

We evaluate how departure from normality may affect the allocation of assets. A Taylor series expansion of the expected utility allows to focus on certain moments and to compute the optimal portfolio allocation numerically. A decisive advantage of this approach is that it remains operational even for a large number of assets. While the mean‐variance criterion provides a good approximation of the expected utility maximisation under moderate non‐normality, it may be ineffective under large departure from normality. In such cases, the three‐moment or four‐moment optimisation strategies may provide a good approximation of the expected utility.     

User experience on mobile video appreciation: How to engross users and to enhance their enjoyment in watching mobile video clips

In the past few years consumers have enjoyed consuming video content on a growing number of devices including the traditional television, personal computers, mobile phone and tablets. Each device has its own technical attributes and associated consumption characteristics. This research examines the differential effects of user experience on engagement during video consumption in the mobile and desktop environments. We have experimented with different situations related to the genre, the sequence of playing, the extent of interruption, the timing of the interruption, and length of the video clips. Our model was quantitatively tested, with 270 users taking part in a between subject experiment.In the mobile environment, our results provide evidence that sensory experience is a significant factor for enjoyment and engagement with the video, while emotional response is not. The reverse is true for the desktop environment. Learning curve factors work differently in the two environments. User enjoyment and engagement are significantly moderated by learning curve factors in the mobile environment only. The result is robust as it is true for both previous learning (usage experience with the device), and on-the-go experience (sequencing of video clips). Attention span only affects engagement and enjoyment in the desktop environment. Outside interruption only affects engagement and enjoyment in the mobile environment.Our findings can inform commercial practices on the video design and user interface, and also enhance our understanding of the contextual dependency of the theoretical concept of engagement in mobile entertainment.     

The foreclosure discount: Myth or reality?

Foreclosed properties sell at lower prices than do nearby non-distressed properties. Of particular concern, is whether there is a “stigma” foreclosure discount whereby REO properties sell at lower prices simply because they have been involved in foreclosure proceedings. To the extent that such a discount exists, arbitrage opportunities exist and the associated market failure has significant policy implications. We examine the foreclosure discount from a different perspective than prior researchers by comparing holding period returns earned by purchasers of REOs with those earned by purchasers of similar non-distressed properties. Our results show that the majority of REO purchasers do not earn economically significant excess returns. On average, the implied market discount is less than typical transaction costs. We also find evidence that REO properties and buyers vary systematically from their counterparts in the non-distressed market segment and that REO attribute prices differ from those of non-distressed properties. Overall, our evidence suggests that the market for REOs operates efficiently: lenders are not irrationally dumping REO properties and REO investors are not reaping extraordinary profits.     

Rural Poverty Dynamics and Impact of Intervention Programs upon Chronic and Transitory Poverty in Northern Ethiopia*

Abstract: Using a three‐year panel data set of rural households in the Tigray region of northern Ethiopia, we examine the dynamics of poverty and the impact of two intervention measures—the food for work (FFW) and the food security package (FSP) programs—upon poverty by disaggregating total poverty into its transient and chronic components. Poverty in the region is predominantly chronic. Results of matching estimators indicate that the FSP program has a significant negative effect on total and chronic poverty, but not on transient poverty. Households involved in the program have on average lower levels of total and chronic poverty than households not involved in the program. The FFW on the other hand does not significantly influence any of the three forms of poverty. Tertile regressions, however, reveal that the FFW benefits households in the richest and the middle tertiles.     

跳出快漩涡

许多顶着“快公司”桂冠的新兴企业曾一度以黑马的姿态赢得众人的关注与赞叹,但人们却很快发现,这些黑马并不一定是千里马,许多会在奔跑中轰然倒下. 每个企业家都正经历着这样的比赛:极度不确定的未来、不可或缺而相当有限的资源、等待实战磨砺的能力,更重要的是耗时漫长.怎样赢得最后的胜利?许多企业家曾一度把“快”当作必杀技.     

Developing a new Multi‐Nation tourism region: Thai perspectives on the Mekong initiatives

This article examines Thailand's recent tourism policy and its attitudes towards international tourism development collaboration in the Greater Mekong Subregion. Thailand is the major tourist destination country and gateway for international tourists visiting the region, and is a leader of Mekong tourism developments. This paper considers the Thai perspective on its tourism development, and examines current co‐operative activities in the Mekong region in the context of its own tourism industry. A number of research needs are sketched out as a proposed framework for future studies.