18,506 research outputs found
Index statistical properties of sparse random graphs
Using the replica method, we develop an analytical approach to compute the
characteristic function for the probability that a
large adjacency matrix of sparse random graphs has eigenvalues
below a threshold . The method allows to determine, in principle, all
moments of , from which the typical sample to sample
fluctuations can be fully characterized. For random graph models with localized
eigenvectors, we show that the index variance scales linearly with
for , with a model-dependent prefactor that can be exactly
calculated. Explicit results are discussed for Erd\"os-R\'enyi and regular
random graphs, both exhibiting a prefactor with a non-monotonic behavior as a
function of . These results contrast with rotationally invariant
random matrices, where the index variance scales only as , with an
universal prefactor that is independent of . Numerical diagonalization
results confirm the exactness of our approach and, in addition, strongly
support the Gaussian nature of the index fluctuations.Comment: 10 pages, 5 figure
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An evaluation of DIADEM assisted online form completion
The DIADEM project aims to develop a web-based application in the form of an Expert System (ES) to assist cognitively impaired older-adult users in the task of interacting with and completing online transactions. Having recently developed the first experimental version of the application, this study reports on the preliminary findings of user trials carried out in three European countries top evaluate this early version of the application. Of the 94 users that took part in the trials, 77 were identified as users that were likely to present with some degree of mild cognitive impairment, and thus were included in the analysis stage. The key findings of the study indicate that users of DIADEM assisted form filling seemed report comparatively high-levels of satisfaction, particularly when considered against what is considered a typical level of satisfaction for this user group. Furthermore, as a result of a statistical analysis, the application appears to provide significantly increased levels of assistance for users presenting with higher levels of cognitive impairments, and therefore achieves its goal of catering for this particular target user group
Transformational government and assistive web base technologies
Transformational government has been on the European agenda for several years. However, progress towards realising the full potential of ICT to transform public services for older adults with age related cognitive impairments has been very limited. Highlighting such limitations this paper demonstrates how assistive web base technologies can be developed to improve the public services for older adults with age related cognitive impairments. However the paper argues that these transformations can be obstructed if there is no strong leadership and political commitment from people at many levels in public sectors and governments
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