Towards a deeper understanding of system usage in organizations: A multi-level perspective

The objective of this paper is to contribute towards a deeper understanding of system usage in organizations by examining its multilevel nature. Past research on system usage has suffered from a levels bias, with researchers studying system usage at single levels of analysis only, e.g., the individual, group, or organizational level. Although single-level research can be useful, we suggest that studying organizations one level at a time will ultimately lead to an unnatural, incomplete, and very disjointed view of how information systems are used in practice. To redress this situation, we draw on recent advances in multilevel theory to present system usage as a multilevel construct and provide an illustration for what it takes for IS researchers to study it as such. The multilevel perspective advanced in this article offers rich opportunities for theoretical and empirical insights and suggests a new foundation for in-depth research on the nature of system usage, its emergence and change, and its antecedents and consequences

Analyzing IT Outscoring Relationships as Alliances among Multiple Clients and Vendors

As the business environment become more uncertain and competitive, many organizations are seeking ways to gain economic efficiency and share in business and technology risk. Despite wide differences in the reference disciplines applied to outsourcing research, the vast majority of it assumes a one-to-one relationship between the client and the outsourcing vendor. This paper examines the economic, strategic, and organizational issues involved in IT outsourcing when more complex arrangements are considered - such as multi-vendor alliances, co-sourcing, and complex multi-vendor, multi-client relationships. In this paper, we identify a taxonomy of four classes of outsourcing relationships (based on how many clients and vendors are involved in the outsourcing relationship, and illustrate each with recent business examples. Grounded in this taxonomy, we develop a theoretical framework that identifies both enabling and constraining forces that may influence client firms in choosing among the four types of outsourcing relationships. This paper provides insights regarding how the variations in the nature of these outsourcing relationships may shape the benefits and risks be achieved from outsourcing, as well as the ongoing complexity of managing outsourcing relationships.Information Systems Working Papers Serie

Measurement of the ΔS=-ΔQ Amplitude from K_(e3)^0 Decay

We have measured the time distribution of the π^+e^-ν and π^-e^+ν modes from initial K^0's in a spark-chamber experiment performed at the Bevatron. From 1079 events between 0.2 and 7 K_S^0 lifetime, we find ReX=-0.069±0.036, ImX=+0.108_(-0.074)^(+0.092). This result is consistent with X=0 (relative probability = 0.25), but more than 4 standard deviations from the existing world average, +0.14 -0.13i

The Quantized O(1,2)/O(2)×Z2O(1,2)/O(2)\times Z_2 Sigma Model Has No Continuum Limit in Four Dimensions. I. Theoretical Framework

The nonlinear sigma model for which the field takes its values in the coset space $O(1,2)/O(2)\times Z_2$ is similar to quantum gravity in being perturbatively nonrenormalizable and having a noncompact curved configuration space. It is therefore a good model for testing nonperturbative methods that may be useful in quantum gravity, especially methods based on lattice field theory. In this paper we develop the theoretical framework necessary for recognizing and studying a consistent nonperturbative quantum field theory of the $O(1,2)/O(2)\times Z_2$ model. We describe the action, the geometry of the configuration space, the conserved Noether currents, and the current algebra, and we construct a version of the Ward-Slavnov identity that makes it easy to switch from a given field to a nonlinearly related one. Renormalization of the model is defined via the effective action and via current algebra. The two definitions are shown to be equivalent. In a companion paper we develop a lattice formulation of the theory that is particularly well suited to the sigma model, and we report the results of Monte Carlo simulations of this lattice model. These simulations indicate that as the lattice cutoff is removed the theory becomes that of a pair of massless free fields. Because the geometry and symmetries of these fields differ from those of the original model we conclude that a continuum limit of the $O(1,2)/O(2)\times Z_2$ model which preserves these properties does not exist.Comment: 25 pages, no figure

Action plan co-optimization reveals the parallel encoding of competing reach movements.

Several influential cognitive theories propose that in situations affording more than one possible target of action, we prepare multiple competing movements before selecting one. Here we provide direct evidence for this provocative but largely untested idea and demonstrate why preparing multiple movements is computationally advantageous. Using a reaching task in which movements are initiated after one of two potential targets is cued, we show that the movement generated for the cued target borrows components of the movement that would have been required for the other, competing target. This interaction can only arise if multiple potential movements are fully specified in advance and we demonstrate that it reduces the time required to launch a given action plan. Our findings suggest that this co-optimization of motor plans is highly automatic and largely occurs outside conscious awareness.The study was supported by the Natural Sciences and Engineering Research Council of Canada; the Wellcome Trust; the Human Frontiers Science Program; and the Royal Society. J.P.G. was supported by Banting postdoctoral fellowship and CIHR postdoctoral fellowship awards.This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/ncomms842

Interpolatory methods for H∞\mathcal{H}_\infty model reduction of multi-input/multi-output systems

We develop here a computationally effective approach for producing high-quality $\mathcal{H}_\infty$-approximations to large scale linear dynamical systems having multiple inputs and multiple outputs (MIMO). We extend an approach for $\mathcal{H}_\infty$ model reduction introduced by Flagg, Beattie, and Gugercin for the single-input/single-output (SISO) setting, which combined ideas originating in interpolatory $\mathcal{H}_2$-optimal model reduction with complex Chebyshev approximation. Retaining this framework, our approach to the MIMO problem has its principal computational cost dominated by (sparse) linear solves, and so it can remain an effective strategy in many large-scale settings. We are able to avoid computationally demanding $\mathcal{H}_\infty$ norm calculations that are normally required to monitor progress within each optimization cycle through the use of "data-driven" rational approximations that are built upon previously computed function samples. Numerical examples are included that illustrate our approach. We produce high fidelity reduced models having consistently better $\mathcal{H}_\infty$ performance than models produced via balanced truncation; these models often are as good as (and occasionally better than) models produced using optimal Hankel norm approximation as well. In all cases considered, the method described here produces reduced models at far lower cost than is possible with either balanced truncation or optimal Hankel norm approximation

Temperature-dependent 2D-3D growth transition of ultra-thin Pt films deposited by PLD

During the growth of metal thin films on dielectric substrates at a given deposition temperature T, the film's morphology is conditioned by the magnitude and asymmetry of up- and downhill diffusion. Any severe change of this mechanism leads to a growth instability, which induces an alteration of the thin film morphology. In order to study this mechanism, ultra-thin Pt films were deposited via pulsed laser deposition (PLD) onto yttria-stabilized-zirconia single crystals at different deposition temperatures. The morphological evolution of Pt thin films has been investigated by means of scanning electron microscopy (SEM), atomic force microscopy (AFM) and standard image analysis techniques. The experimentally obtained morphologies are compared to simulated thin film structures resulting from a two-dimensional kinetic Monte Carlo (KMC) approach. Two main observations have been made: i) Thin Pt films deposited onto zirconia undergo a growth transition from two-dimensional to three-dimensional growth at T > 573 K. The growth transition and related morphological changes are a function of the deposition temperature. ii) A critical cluster size of i\ast = 4 in combination with an asymmetric Ehrlich-Schwoebel (ES) barrier favoring the uphill diffusion of atoms allows for a computational reproduction of the experimentally obtained film morphologies.Comment: 7 pages, 6 figures, 1 tabl

Are Citations to Academic Journal Articles a Measure of Quality or Something Else? An Exploratory Analysis with Emphasis on Design Science and IS Technical Research

One pervasive belief about scholarly citations that underlies several studies appearing in the IS literature is that the number ofcitations to a paper reflects the quality of the study. For example, a paper that receives 200 citations is perceived as havinghigher quality than another study that receives 50 citations. While most experts acknowledge that there are other factors thatdrive citations, such as the number of years a paper was available to be cited – or possibly “gaming” of citations by authorswho cite themselves frequently (author self-citations) or over-zealous editors who incent prospective authors to cite theirjournals (journal self-citations), there is an underlying assumption that, barring such unscrupulous behavior, citations are ameasure of research quality. This paper critically examines this assumption using a validated typology identifying 13 distinctsubject areas that characterize IS research. Results show that papers on some topics (e.g., IT adoption and use; newmeasurement development and validation) consistently receive more citations than average – while some topics consistentlyreceive below-average citation rates (e.g., IS development; IT project/risk management). Unless one assumes that all paperson a given topic are consistently of higher quality than all papers on other topics, our data suggest that a key driver ofcitations are the subject area of the study and, in turn, the size of the research community that conducts research on the topic

Ixodid ticks of impala (Aepyceros melampus) in Swaziland: effect of age class, sex, body condition and management

Five species of ixodid ticks, Amhlyomma hebraeum, Boophilus decoloratus, Rhipicephalus appendiculatus, R. evertsi evertsi and R. muehlensi, were commonly collected from impala (Aepyceros melampus) in the Mlawula-Mbuluzi-Simunye Nature Reserve and Protected Area complex in north-eastern Swaziland. The prevalence and apparent intensity of infestation of most tick species was greater on yearlings (13-24 months of age) and adults (> 24 months) than on lambs (≤12 months), and on adult males than on adult females. The packed cell volume and marrow dry weight were lower in impala infested with A. hebraeum, and in lambs and adults with moderate to heavy loads of R. muehlensiand/or R. appendiculatus. The age and sex patterns of tick infestation were probably determined by both body condition and host behaviour. The prevalence and apparent intensity of infestation of most tick species was greater in the unmanaged, densely populated area of the reserve than in the managed area from which impala had been culled. This trend was consistent in all months, and in all age classes