The use of phase-type models for disability insurance calculations

This paper explores the use of phase-type models in actuarial calculations for disability insurance. We demonstrate that the changes in status of disability insureds can be appropriately captured by a phase-type model. Our model represents the aging process as the passage through a number of phases of decreasing vitality. When disabled, individuals additionally pass through several stages that represent duration of disability. Recovery and mortality rates from the earlier stages are greater than those in later stages. Using such a model, explicit and easily calculable expressions are obtained for relevant probabilities and actuarial present values. This facilitates the calculation of premiums and reserves.     

Sustainable Supplier Selection in Megaprojects: Grey Ordinal Priority Approach

Due to mounting environmental and social challenges, supplier selection has become one of the most critical tasks of project-oriented organizations. Because supplier selection can affect the long-term success and profitability of the organizations and their projects, directly, embracing sustainability can add value in the equation. Considering sustainability measures can positively guide project managers in making better decisions for the projects in the long term. Therefore, the current study attempts to provide a conceptual model for selecting the best supplier based on a sustainability framework in megaprojects. Meanwhile, decision-making methods can be employed as a proper tool to find the best supplier. Ordinal priority approach (OPA) is a recent development in multiple criteria decision making (MCDM), while it has many benefits compared with other methods like analytic hierarchy process (AHP) and technique for order of preference by similarity to ideal solution (TOPSIS). However, this method cannot consider multiple ranks during the decision-making process, and using an uncertainty approach feels strongly. Grey systems theory (GST) can consider uncertainties with no need for large sample or proposing membership function. Hence, the current study employed the GST to consider multiple ranks for criteria and alternatives in the OPA method. This is the first time that a sustainable supplier selection framework has been presented for megaprojects with the aid of the Grey OPA (OPA-G) method. Finally, a case study has been examined to evaluate the performance of the proposed approach. The results show that the proposed approach can be used in real-world situations and it has acceptable performance under uncertainty conditions.     

Role of tariffs,imports substitution and investment efficiency in economic growth of Pakistan

Quality & Quantity - This paper explores the impact of tariffs, imports substitution and investment efficiency on economic growth in Pakistan. For this purpose, secondary data was collected...     

Backyard Hog Production Efficiency: Evidence from the Philippines*

This article investigates the economic efficiency and the factors associated with efficiency for a sample of 126 hog producers in the Philippines. The input‐oriented efficiency indices are computed and bootstrapped using data envelopment analysis. Econometric analysis of the factors influencing the efficiency indices are conducted using the Tobit model. Fixed capital does not influence the efficiency scores, whereas labor does negatively influence the efficiency indices. On average, technical efficiency is low, an indication that most households are not using the most efficient technology. Scale efficiency is fairly high but constrained by lack of operating capital and managerial skills. Technical efficiency is constrained by lack of access to credit and limited experience in hog production.     

An analysis of reported driver behaviour in samples of domestic and expatriate Iranians

Objective: Few studies have examined the differences in self-reported driver behaviour between drivers of one nationality who live in their country of origin (domestic drivers) and those who live abroad (expatriate drivers). This study aimed to explore the differences in self-reported driver behaviour among domestic and expatriate Iranian drivers. In addition, we explore the factors associated with self-reported accident involvement including personal injuries in these groups. Methods: A web-based version of the Driver Behaviour Questionnaire (DBQ) measuring self-reported driver errors and violations was distributed to respondents by availability sampling in social networks and by bulk email services. About 1000 individuals living in all provinces in Iran were invited to participate in the survey. We also invited Iranians living in more than 20 countries. A total of 634 domestic Iranians and 135 expatriate Iranians responded to our enquiry. The measure of driving behaviour asked the respondents about violations and error conduct during the last two years on any kind of road. The sample of domestic and expatriate drivers did not differ significantly in gender, age, education and driving hours per day. Domestic drivers were more likely to have experienced an accident in their lifetime. Both samples were relatively young of age (Domestic M integer?=?28.53, SD?=?6.85; Expatriate M integer?=?29.21, SD?=?7.71). Results: The results suggested that emotional violations were more common among the drivers living in Iran. Emotional violations and driver errors were related to self-reported accident involvement among domestic drivers while ordinary rule violations were associated with such accidents in the expatriate group. Conclusions: Iranian expatriate drivers reported less emotional violations than domestic drivers. A potential reason is that road traffic infrastructure and regulation enforcement in high-income developed countries do not facilitate emotional violations. Implications for road traffic safety and methodological limitations of the study are discussed.     

基于演化计算的Hopfield神经网络多用户检测模型研究

人们已经对Hopfield神经网络应用于多用户检测进行了大量研究,但Hopfield神经网络多用户检测模型存在局部最优和稳定性差的问题一直没有得到有效解决。演化计算的高度并行与自组织、自适应和自学习等特点正好能有效解决稳定性差与局部最优的问题。因此,文章在考虑随机扰动变量的前提下,将演化计算结合进Hopfield神经网络多用户检测模型中。理论推导证明,该方法切实可行,预计有很好的应用前景。     

Trade facilitation and country size

It is argued that compared with large countries, small countries rely more on trade and therefore are more likely to adopt liberal trading policies. The present paper extends this idea beyond the conventional trade openness measures by analyzing the relationship between country size and the number of documents required to export and import, a measure of trade facilitation. Three important results follow. First, trade facilitation does improve as country size becomes smaller; that is, small countries perform better than large countries in terms of trade facilitation. Second, the relationship between country size and trade facilitation is nonlinear, much stronger for the relatively small than the large countries. Third, contrary to what existing studies might suggest, the relationship between country size and trade facilitation does not appear to be driven by the fact that small countries trade more as a proportion of their gross domestic product than the large countries.     

A Comparative Analysis of Global Halal Certification Requirements

The aim of this study is to compare the various Halal certification bodies around the world based on the criteria for Halal certification. As the process of awarding Halal certificates varies among the certification bodies, it is pertinent to identify the differences between these selected certification bodies to gauge the gap existing among them. This study will also identify the position of JAKIM, which is the main Halal certification body in Malaysia, among the other main certification bodies around the world. Nine categories were identified in awarding Halal certification to companies. Comparative analysis was then used to see the differences that exist between these certification bodies. The results of the analysis indicate that, based on the nine categories identified, JAKIM is the strictest body in awarding Halal certification to companies.