Joint Modeling of Survival and Longitudinal Ordered Data Using a Semiparametric Approach

Medical research frequently focuses on the relationship between quality of life (QoL) and survival time of subjects. QoL may be one of the most important factors that could be used to predict survival, making it worth identifying factors that jointly affect survival and QoL. We propose a semiparametric joint model that consists of item response and survival components, where these two components are linked through latent variables. Several popular ordinal models are considered and compared in the item response component, while the Cox proportional hazards model is used in the survival component. We estimate the baseline hazard function and model parameters simultaneously, through a profile likelihood approach. We illustrate the method using an example from a clinical study.     

Supply risk mitigation: a multi-theoretical perspective

Due to the increasing level of supply risk, it is imperative to obtain a better understanding of the nature of risk which is a premise to developing well-grounded risk mitigation strategies. This paper examines how to mitigate supply risk enlightened by discussing the concept of risk in association of three closely related concepts which are uncertainty, variability and trust. The proposed three perspectives are supported and explained using four case studies comprising of two manufacturers based in Australia and four suppliers based in China. The study provides evidence that supply risk can be mitigated by high level of information and knowledge sharing as well as building trust, commitment and goal congruence in a buyer–supplier relationship. It offers theoretical and managerial implications.     

Line balance analyses for system assembly lines in an electronic plant

This research analysed and optimised the assembly line balance of notebook computer system production lines in a major computer plant. The research developed a mathematical model for balancing assembly lines of a specific notebook computer system. Precedence relationship charts were created to enforce the required sequences and ILOG CPLEX software was used to obtain the optimal solution of the task assignments to the workstations. The new task assignments were simulated to verify the improvement recommendations and predict the potential benefits.The estimated improvements include: (1) 5.9% increase in average daily production; (2) 29% decrease in average daily WIP; (3) 67.9% reduction in cycle time; (4) 16.7% reduction in operator headcount over the whole system assembly area. The contributions of this research include: (1) Establishing line balancing mathematical model suitable for notebook computer factories; (2) Optimising the system assembly lines for the subject company; (3) Transferring the line balance modelling and optimisation techniques for company use.     

Online algorithms for maximizing weighted throughput of unit jobs with temperature constraints

We consider a temperature-aware online deadline scheduling model. The objective is to schedule a number of unit jobs, with release dates, deadlines, weights and heat contributions, to maximize the weighted throughput subject to a temperature threshold. We first give an optimally competitive randomized algorithm. Then we give a constant competitive randomized algorithm that allows a tradeoff between the maximum heat contribution of jobs and the competitiveness. Finally we consider the multiple processor case and give several tight upper and lower bounds.     

Oops! and Another Seemingly Four-Letter Word

Performance engineering, SPC, and the Total Performance System are related to one another. Their similarities and differences are noted. Examples of their joint applications are presented in case analyses. It is suggested that we can combine behavior analysis techniques with SPC techniques to construct total performance systems.     

Do service-oriented IT architectures facilitate business process outsourcing?

How does a firm’s IT architecture affect its potential to outsource business processes? As Information Technology (IT) has become many firms’ essential operational infrastructure or “backbone”, we are interested in scrutinizing to what extent the kind of IT architecture affects a firm’s boundaries or the plasticity of its boundaries. Focusing on the particular concept of service-oriented architectures (SOA), we concretely ask: How does SOA affect business process outsourcing potentials? Since SOA is widely expected to modularize the IT implementation of business processes, it should increase business process outsourcing (BPO) in terms of buying in the provision of single business functionalities. We develop and empirically evaluate a theoretical model that conceptualizes the relationship between SOA and BPO. Questionnaire data from 115 firms give first evidence that SOA facilitates BPO. By increasing IT modularity, SOA supports BPO by increasing sourcing flexibility and, in particular, operational benefits, while at the same time lowering financial risks and strategic risks, such as lock-in. Overall, however, firms see SOA-based BPO mainly in an operational context with low hidden costs and little strategic benefits.     

Acting Surprised: Comparing Perceptions of Different Dynamic Deliberate Expressions

Journal of Nonverbal Behavior - People are accurate at classifying emotions from facial expressions but much poorer at determining if such expressions are spontaneously felt or deliberately posed....     

On the functional form of temporal discounting: An optimized adaptive test

The tendency to discount the value of future rewards has become one of the best-studied constructs in the behavioral sciences. Although hyperbolic discounting remains the dominant quantitative characterization of this phenomenon, a variety of models have been proposed and consensus around the one that most accurately describes behavior has been elusive. To help bring some clarity to this issue, we propose an Adaptive Design Optimization (ADO) method for fitting and comparing models of temporal discounting. We then conduct an ADO experiment aimed at discriminating among six popular models of temporal discounting. Rather than supporting a single underlying model, our results show that each model is inadequate in some way to describe the full range of behavior exhibited across subjects. The precision of results provided by ADO further identify specific properties of models, such as accommodating both increasing and decreasing impatience, that are mandatory to describe temporal discounting broadly.     

The Universal Decline of Universality? Social Policy Change in Canada,Denmark, Sweden and the UK

The debate about the future of universal social programmes has been raging for years, both in social‐democratic and in liberal welfare states. The objective of this article is to contribute to the literature on universality by analyzing the evolution of universal social programmes in two social‐democratic and two liberal countries: Denmark, Sweden, Canada and the UK. This choice of countries provides the opportunity to investigate whether the principle and practice of universality has fared differently both within and between countries. The analysis focuses primarily on the national level while exploring three policy areas: pensions, healthcare and family policy, specifically child benefits and day care. The main conclusion of our comparative analysis is clear: among our two liberal and two social‐democratic countries, the institutional strength of universality varies greatly from one policy area and one country to another. Considering this, there is no such a thing as a universal decline of universality.     

What drives unconventional political participation? A two level study

There is little evidence on the factors that drive peaceful unconventional political participation. This study evaluates the impact of seven individual level constituents – age, income, education, gender, satisfaction with the government, engagement in civil society organizations and voting – as well as five macro-level factors – economic development, democratic experience, income inequalities, a country's regime type and federalism – on citizens’ participation in boycotts, demonstrations and petition signing activities. Participation in all three protest activities hinges on education, voting, participation in civil society organizations, and lack of satisfaction with the government. Moreover, the influence of some macro-factors, such as democratic experience and economic development, and micro-level factors, such as gender differs between the three forms of political engagement.