Tugrul U. Daim

Using artificial neural network models in stock market index prediction

Forecasting stock exchange rates is an important financial problem that is receiving increasing attention. During the last few years, a number of neural network models and hybrid models have been proposed for obtaining accurate prediction results, in an attempt to outperform the traditional linear and nonlinear approaches. This paper evaluates the effectiveness of neural network models which are known to be dynamic and effective in stock-market predictions. The models analysed are multi-layer perceptron (MLP), dynamic artificial neural network (DAN2) and the hybrid neural networks which use generalized autoregressive conditional heteroscedasticity (GARCH) to extract new input variables. The comparison for each model is done in two view points: Mean Square Error (MSE) and Mean Absolute Deviate (MAD) using real exchange daily rate values of NASDAQ Stock Exchange index.

Multi-Criteria Applications in Renewable Energy Analysis, a Literature Review

Energy impacts so many aspects of our lives. This makes it necessary to evaluate multiple aspects when we are evaluating energy alternatives. This chapter introduces us to a spectrum of tools for this evaluation.

Adoption Factors of Mobile Services

As more and more mobile services become available everyday, consumers are choosing different services based on their preferences. Exploring and understanding this phenomenon is critical. This paper presents a framework for defining the adoption factors of mobile services. The framework builds upon current approaches to explain adoption factors. A survey instrument was utilized for data collection. Two different types of service were compared through the study. The findings were confirming the literature for an already adopted service and indicating that usefulness and attitude are direct factors influencing consumer satisfaction. On the other hand, usefulness and external influence were found to be direct; and personalization, image, content, mobility, enjoyment as indirect determinants of consumer’s attitude towards using new mobile services.

Developing Oregon's renewable energy portfolio using fuzzy goal programming model

Renewable energy continues to be a hot topic in the United States affecting security and sustainability. A model to create renewable energy portfolio is established using guidelines drawn by Oregons Renewable Portfolio Standard (RPS) legislation with the objective of responding to a 25% of the state electricity demand by renewable resources in 2025. The fuzzy goal programming model is adaptable to accommodate changes in energy costs and future advances in technology maturity. It can also take into consideration the preferences of policy-makers and stakeholders. This model can help to reveal the costs and benefits of complex decisions regarding renewable energy.

A critical assessment of information technology adoption: technical, organisational and personal perspectives

In todays rapidly changing competitive environment, information technology (IT) within an organisation is continuously improved, driven by external push of technological advances and internal pull of increasing organisational needs. In order to achieve the greatest return on IT investment, the diffusion process of IT within the organisation should be examined carefully. This study aims to explore the effects of technical, organisational and personal characteristics on the diffusion of different information technologies within organisations, and to discover the relationship between the diffusion and infusion of these technologies and the effectiveness, efficiency and productivity of managerial decision making processes. Based on a thorough review of theoretical background and prior empirical studies in the area, an integrated research framework concerning IT diffusion context has been developed and tested via a survey applied on individuals from different organisations. Findings suggest that the antecedents of the diffusion patterns vary for different types of information technologies.

Exploring gender differences in attitudes of university students towards entrepreneurship

Purpose – The purpose of this paper is to understand gender differences in entrepreneurial intentions as measured by perceived feasibility and perceived desirability, and to explore gender differences in perceptions of entrepreneurship education needs – in terms of programmes, activities or projects – to succeed in an entrepreneurial career from the university students point of view.Design/methodology/approach – Using data gathered from 3,420 university students in more than ten countries, and applying the Mann‐Whitney non‐parametric test, differences between genders and different intention groups were examined. To reduce the items regarding educational needs, factor analysis was used. Gender differences in educational needs were also examined via Mann‐Whitney Test.Findings – The results confirm that compared to males, female students are less willing to start their own businesses. There are significant gender differences in terms of perceived feasibility and perceived desirability such that although the...

Interface feature prioritization for web services: Case of online flight reservations

Acceptance, utility, and usability of system designs have become a focal interest in human-computer interaction (HCI) research, yet at present there is a lack detailed understandings of which system design features influence them. The purpose of the study is to examine the effects of five product design features; customization, adaptive behavior, memory load, content density, and speed on user preference through an experimental study by using conjoint analysis. In experimental study, instead of classical conjoint cards, prototypes were generated for products. Besides, desirability and market segments of product prototypes were identified. In line with the results, among the five product design features, speed is the most and customization is the least important features that affect user preference. Contrary to the expectations, customization has a relatively small importance value in this research. Subsequent design features that influence user preference after speed are minimal memory load, adaptive behavior, and content density, respectively. According to findings, interfaces that have high-speed, minimal memory load, adaptive behavior, low content density, and customization features are more preferable than those that do not.

Managing Global Design Teams

OVERVIEW: Geographically distributed design teams have become crucial, yet a significant number fail to accomplish their objectives. The reason is that long distances and cultural differences compromise working relationships, communications, trust, accountability, organization, individual contribution, and thus productivity. This paper analyzes eight such teams in the high-tech industry and discusses the most common issues/problems that surround them. These are categorized as technological, organizational and personal. An expert panel assigns a score to the problems and provides a set of recommendations that can improve productivity and minimize failure in such virtual teams.

Data center metrics

Purpose – The purpose of this paper is to identify energy efficiency metrics that can be used by IT managers to measure and maintain the implementation of cost savings and green initiatives in data centers.Design/methodology/approach – The paper looks at the background of the problem and explores the reasons why energy savings in the data center are an important issue. Included are interviews and survey results from IT professionals serving at four unique organizations. A model of the measurable components of a data center is created to provide a framework for organizing metrics and communicating results throughout the corporation. The strengths and weaknesses of two of the most common data center metrics, PUE and DCP, are examined closely.Findings – The paper concludes with future metric recommendations and a proposed credit‐based system that could be applied to encourage closer management of these metrics.Practical implications – The metric recommendations can be used by IT managers resulting in energy ...

Determining Patient Preferences for Remote Monitoring

This paper presents the patient preferences for an application in remote health monitoring. The data was collected through a mobile service prototype. Analytical Hierarchy Process and Conjoint Analysis were used to extract the patient preferences. The study was limited to diabetes and obesity patients in Istanbul, Turkey. Results indicated that sending users’ data automatically, availability of technical support, and price are key factors impacting patient’s decisions. This implies that e-health service providers and designers should focus on the services that enable users to send measurement results automatically instead of manually.