1,720,997 research outputs found
Multivariate hierarchical analysis of car crashes data considering a spatial network lattice
Full text linkRoad traffic casualties represent a hidden global epidemic, demanding
evidence-based interventions. This paper demonstrates a network lattice
approach for identifying road segments of particular concern, based on a case
study of a major city (Leeds, UK), in which 5,862 crashes of different
severities were recorded over an eight-year period (2011-2018). We consider a
family of Bayesian hierarchical models that include spatially structured and
unstructured random effects, to capture the dependencies between the severity
levels. Results highlight roads that are more prone to collisions, relative to
estimated traffic volumes, in the northwest and south of city-centre. We
analyse the Modifiable Areal Unit Problem (MAUP), proposing a novel procedure
to investigate the presence of MAUP on a network lattice. We conclude that our
methods enable a reliable estimation of road safety levels to help identify
"hotspots" on the road network and to inform effective local interventions.Comment: 23 pages, 5 tables, 8 figure
OpenTripPlanner for R
Full text linkopentripplanner provides functions that enable multi-modal routing in R. It provides an interface to the OpenTripPlanner (OTP) Java routing service, which allows calculation of routes on large transport networks, locally or via calls to a remote server. The package contains three groups of functions for: (1) setting up and managing a local instance of OTP; (2) connecting to OTP locally or remotely; and (3) sending requests to the OTP API and importing the results and converting them into appropriate classes for further analysis
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Introducing spatial microsimulation with R: a practical
Full text linkThis practical teaches the basic theory and practice of `spatial microsimulation' using the popular
free software package R. The term microsimulation means different things in different disciplines,
so it is important to be clear at the outset what we will and will not be covering.
We will be learning how to create spatial microdata, the basis of all spatial microsimulation
models, using iterative proportional fitting (IPF). IPF is an efficient method for allocating in-
dividuals from a non-spatial dataset to geographical zones, analogous to the `Furness method'
in transport modelling, but with more constraints. There are other ways of generating spatial
microdata but, as far as the author is aware,1 this is the most effective and flexible for many
applications. An alternative approach using the open source `Flexible Modelling Framework' program is described in detail, with worked examples, by Harland (2013).
We will not be learning `dynamic spatial microsimulation' (Ballas et al., 2005): once the spatial
microdata have been generated and integerised, it is up to the user how they are used, be it in an agent based model or as a basis for estimates of income distributions at the local level or whatever.
We thus define spatial microsimulation narrowly in this tutorial as the process of generating spatial microdata (more on this below). The term can also be used to describe a wider approach that harnesses individual-level data allocated to zones for investigating phenomena that vary over space and between individuals such as income inequality or energy overconsumption. In both cases, the generation of spatial microdata is the critical element of the modelling process so the skills learned in this tutorial will provide a firm foundation for further work
- …
