On n-sum of an abelian group of order n

Let $G$ be an additive finite abelian group of order $n$, and let $S$ be a sequence of $n+k$ elements in $G$, where $k\geq 1$. Suppose that $S$ contains $t$ distinct elements. Let $\sum_n(S)$ denote the set that consists of all elements in $G$ which can be expressed as the sum over a subsequence of length $n$. In this paper we prove that, either $0\in \sum_n(S)$ or $|\sum_n(S)|\geq k+t-1.$ This confirms a conjecture by Y.O. Hamidoune in 2000

Development of a Measure to Assess the Complexity of Information Systems Development Projects

Information systems development (ISD) projects are becoming increasingly complex. ISD project complexity makes it difficult for project managers to deliver effective systems within time and budget constraints. As a result, the success of ISD projects is increasingly dependent on an organizationís ability to effectively assess and manage complexity. The purpose of this paper is to develop a measure for assessing ISD project complexity. A two-dimensional conceptual framework is proposed to define four distinct types of software project complexity: structural organizational complexity, structural IT complexity, dynamic organizational complexity, and dynamic IT complexity. Based on field interviews, focus group discussions, and a large-scale survey of ISD project managers, a measure of ISD project complexity with 17 indicators was developed. The results of an exploratory data analysis provide strong evidence that the final measure has satisfactory measurement properties. The contributions of this research to both theory development and practice are discussed

The Influence of Persuasion, Training, and Experience on User Perceptions and Acceptance of IT Innovation

Information technology (IT) cannot produce any positive outcome unless it is adopted and used. Theories and empirical research suggest that IT adoption and usage are determined by user beliefs and attitudes toward IT. However, little is known about what factors affect the formation and change over time of user beliefs and attitudes. It is critical to understand such factors so that effective managerial interventions can be created and implemented to positively influence user acceptance and use of IT innovations. Based on theories of innovation diffusion, information technology adoption, and persuasion, this study investigates the effect of persuasion, training, and direct-use experience on the formation and change over time of user perceptions and adoption decisions of IT innovation. The results of a longitudinal experimental study show that persuasion significantly affects the formation of users’ initial perceptions, attitude toward, and intention to adopt IT. Training provided in the introduction stage of IT innovation helps the user form a more realistic expectation. As users’ direct-use experience with IT innovation increases over time, their perceptions and adoption intentions change substantially. The results suggest that persuasion, training, and direct-use experience are important variables that need to be considered in IT innovation and adoption research and practice

ICT-enabled autonomy and control in Covid-19 remote work

To maintain business continuity during the COVID-19 pandemic, organizations have relied on various information and communication technologies (ICT). These technologies can be considered both a facilitator of telework activities (such as by supporting contact) and an inhibitor of behaviors associated with them (e. g. workers may find it stressful to share their personal lives on video). Particularly crucial trend which arose is the increasing tension between employee autonomy and employer control – epitomized, for instance, in their ICT use. As remote (and hybrid) work arrangements are expected to constitute long-term solutions, we aim to examine ICT feature use, its role in employer control, and its function in employee willingness to return to onsite placement

Two-Sample Covariance Matrix Testing and Support Recovery

This paper proposes a new test for testing the equality of two covariance matrices Σ1 and Σ2 in the high-dimensional setting and investigates its theoretical and numerical properties. The limiting null distribution of the test statistic is derived. The test is shown to enjoy certain optimality and to be especially powerful against sparse alternatives. The simulation results show that the test significantly outperforms the existing methods both in terms of size and power. Analysis of prostate cancer datasets is carried out to demonstrate the application of the testing procedures. When the null hypothesis of equal covariance matrices is rejected, it is often of significant interest to further investigate in which way they differ. Motivated by applications in genomics, we also consider two related problems, recovering the support of Σ1 − Σ2 and testing the equality of the two covariance matrices row by row. New testing procedures are introduced and their properties are studied. Applications to gene selection is also discussed

Collaboration in Agile Software Development: Concept and Dimensions

One of the four values listed in the Agile Manifesto emphasizes customer collaboration over contract negotiation, yet the literature has not explained what constitutes customer collaboration and how to assess it. Little research has examined the nature and dimensions of collaboration in the context of agile software development. Based on a grounded theory methodology and using interview data collected from five software development outsourcing vendors in China, we explore the nature and key underlying dimensions of collaboration in agile software development. Five major dimensions of collaboration emerged from our analysis: mutual benefits, engagement, coordination, communication, and knowledge sharing. In turn, each dimension comprises key subdimensions that provide a comprehensive view of collaboration. By revealing the underlying nature and key dimensions, we provide a conceptual basis for operationalizing collaboration that one can employ in future quantitative studies on agility and other project outcomes. Our study results suggest that collaboration in agile software development is multifaceted and mutually occurring in both directions between the customer and the vendor rather than single dimensional as the term “customer collaboration” in the Agile Manifesto indicates