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The impact of organisational culture on WiMax adoption by Saudi SMEs
Although there is some research that examines Worldwide Inter-operability for Microwave Access (WiMax) adoption, the role of the organisational culture by Small and Medium Enterprises (SMEs) has not been studied in the context of the Kingdom of Saudi Arabia (KSA). This paper presents the outcome of a study carried out to examine the impact of organisational culture on the WiMax adoption by SMEs in the KSA. Based on Cameron and Quinn's Organisational Culture Assessments Instrument (OCAI), 63 questionnaires were distributed to different SMEs in Saudi Arabia. The results showed that there is a relatively low level of WiMax adoption by Saudi SMEs. Findings stated that Saudi SMEs are dominated by the clan culture where people are less innovative than the people in adhocracy culture
AutoParallel: A Python module for automatic parallelization and distributed execution of affine loop nests
The last improvements in programming languages, programming models, and
frameworks have focused on abstracting the users from many programming issues.
Among others, recent programming frameworks include simpler syntax, automatic
memory management and garbage collection, which simplifies code re-usage
through library packages, and easily configurable tools for deployment. For
instance, Python has risen to the top of the list of the programming languages
due to the simplicity of its syntax, while still achieving a good performance
even being an interpreted language. Moreover, the community has helped to
develop a large number of libraries and modules, tuning them to obtain great
performance.
However, there is still room for improvement when preventing users from
dealing directly with distributed and parallel computing issues. This paper
proposes and evaluates AutoParallel, a Python module to automatically find an
appropriate task-based parallelization of affine loop nests to execute them in
parallel in a distributed computing infrastructure. This parallelization can
also include the building of data blocks to increase task granularity in order
to achieve a good execution performance. Moreover, AutoParallel is based on
sequential programming and only contains a small annotation in the form of a
Python decorator so that anyone with little programming skills can scale up an
application to hundreds of cores.Comment: Accepted to the 8th Workshop on Python for High-Performance and
Scientific Computing (PyHPC 2018
Matchmaker, Matchmaker, Make Me a Match: Migration of Populations via Marriages in the Past
The study of human mobility is both of fundamental importance and of great
potential value. For example, it can be leveraged to facilitate efficient city
planning and improve prevention strategies when faced with epidemics. The
newfound wealth of rich sources of data---including banknote flows, mobile
phone records, and transportation data---has led to an explosion of attempts to
characterize modern human mobility. Unfortunately, the dearth of comparable
historical data makes it much more difficult to study human mobility patterns
from the past. In this paper, we present an analysis of long-term human
migration, which is important for processes such as urbanization and the spread
of ideas. We demonstrate that the data record from Korean family books (called
"jokbo") can be used to estimate migration patterns via marriages from the past
750 years. We apply two generative models of long-term human mobility to
quantify the relevance of geographical information to human marriage records in
the data, and we find that the wide variety in the geographical distributions
of the clans poses interesting challenges for the direct application of these
models. Using the different geographical distributions of clans, we quantify
the "ergodicity" of clans in terms of how widely and uniformly they have spread
across Korea, and we compare these results to those obtained using surname data
from the Czech Republic. To examine population flow in more detail, we also
construct and examine a population-flow network between regions. Based on the
correlation between ergodicity and migration in Korea, we identify two
different types of migration patterns: diffusive and convective. We expect the
analysis of diffusive versus convective effects in population flows to be
widely applicable to the study of mobility and migration patterns across
different cultures.Comment: 24 pages, 23 figures, 5 table
Project Quality of Offshore Virtual Teams Engaged in Software Requirements Analysis: An Exploratory Comparative Study
The off-shore software development companies in countries such as India use a global delivery model in which initial requirement analysis phase of software projects get executed at client locations to leverage frequent and deep interaction between user and developer teams. Subsequent phases such as design, coding and testing are completed at off-shore locations. Emerging trends indicate an increasing interest in off-shoring even requirements analysis phase using computer mediated communication. We conducted an exploratory research study involving students from Management Development Institute (MDI), India and Marquette University (MU), USA to determine quality of such off-shored requirements analysis projects. Our findings suggest that project quality of teams engaged in pure off-shore mode is comparable to that of teams engaged in collocated mode. However, the effect of controls such as user project monitoring on the quality of off-shored projects needs to be studied further
Truss Decomposition in Massive Networks
The k-truss is a type of cohesive subgraphs proposed recently for the study
of networks. While the problem of computing most cohesive subgraphs is NP-hard,
there exists a polynomial time algorithm for computing k-truss. Compared with
k-core which is also efficient to compute, k-truss represents the "core" of a
k-core that keeps the key information of, while filtering out less important
information from, the k-core. However, existing algorithms for computing
k-truss are inefficient for handling today's massive networks. We first improve
the existing in-memory algorithm for computing k-truss in networks of moderate
size. Then, we propose two I/O-efficient algorithms to handle massive networks
that cannot fit in main memory. Our experiments on real datasets verify the
efficiency of our algorithms and the value of k-truss.Comment: VLDB201
Generic Machine Learning Inference on Heterogenous Treatment Effects in Randomized Experiments
We propose strategies to estimate and make inference on key features of
heterogeneous effects in randomized experiments. These key features include
best linear predictors of the effects using machine learning proxies, average
effects sorted by impact groups, and average characteristics of most and least
impacted units. The approach is valid in high dimensional settings, where the
effects are proxied by machine learning methods. We post-process these proxies
into the estimates of the key features. Our approach is generic, it can be used
in conjunction with penalized methods, deep and shallow neural networks,
canonical and new random forests, boosted trees, and ensemble methods. It does
not rely on strong assumptions. In particular, we don't require conditions for
consistency of the machine learning methods. Estimation and inference relies on
repeated data splitting to avoid overfitting and achieve validity. For
inference, we take medians of p-values and medians of confidence intervals,
resulting from many different data splits, and then adjust their nominal level
to guarantee uniform validity. This variational inference method is shown to be
uniformly valid and quantifies the uncertainty coming from both parameter
estimation and data splitting. We illustrate the use of the approach with two
randomized experiments in development on the effects of microcredit and nudges
to stimulate immunization demand.Comment: 53 pages, 6 figures, 15 table
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