Auditing the accessibility of Massive Open Online Courses (MOOCs)

The outcome from the research being reported in this paper is the design of an accessibility audit to evaluate Massive Open Online Courses (MOOCs) for accessibility and to arrive at solutions and adaptations that can meet user needs. This accessibility audit includes expert-based heuristic evaluations and user-based evaluations of the MOOC platforms and individual courses

Writing about accessibility

In this forum we celebrate research that helps to successfully bring the benefits of computing technologies to children, older adults, people with disabilities, and other populations that are often ignored in the design of mass-marketed products. --- Juan Pablo Hourcade, Editor </jats:p

Accessibility of Vendor-Created Video Tutorials for People with Disabilities

Many video, screencast, webinar, or interactive tutorials are created and provided by vendors for use by libraries to instruct users in database searching. This study investigates whether these vendor-created database tutorials are accessible for people with disabilities to see whether librarians can use these tutorials instead of creating them in-house. Findings on accessibility were mixed. Positive accessibility features and common accessibility problems are described, with recommendations on how to maximize accessibility

Improving accessibility at airports

Analyse and evaluate the accessibility at airports to improve the role of this infrastructure at regional level

Accessibility percolation with backsteps

Consider a graph in which each site is endowed with a value called \emph{fitness}. A path in the graph is said to be "open" or "accessible" if the fitness values along that path is strictly increasing. We say that there is accessibility percolation between two sites when such a path between them exists. Motivated by the so called House-of-Cards model from evolutionary biology, we consider this question on the $L$-hypercube $\{0,1\}^L$ where the fitness values are independent random variables. We show that, in the large $L$ limit, the probability that an accessible path exists from an arbitrary starting point to the (random) fittest site is no more than $x^*_{1/2}= 1-\frac12\sinh^{-1}(2) =0.27818\ldots$ and we conjecture that this probability does converge to $x^*_{1/2}$. More precisely, there is a phase transition on the value of the fitness $x$ of the starting site: assuming that the fitnesses are uniform in $[0,1]$, we show that, in the large $L$ limit, there is almost surely no path to the fittest site if $x>x^*_{1/2}$ and we conjecture that there are almost surely many paths if $x<x^*_{1/2}$. If one conditions on the fittest site to be on the opposite corner of the starting site rather than being randomly chosen, the picture remains the same but with the critical point being now $x^*_1= 1-\sinh^{-1}(1)= 0.11863\ldots$. Along the way, we obtain a large $L$ estimation for the number of self-avoiding paths joining two opposite corners of the $L$-hypercube

Evolutionary accessibility of mutational pathways

Functional effects of different mutations are known to combine to the total effect in highly nontrivial ways. For the trait under evolutionary selection (`fitness'), measured values over all possible combinations of a set of mutations yield a fitness landscape that determines which mutational states can be reached from a given initial genotype. Understanding the accessibility properties of fitness landscapes is conceptually important in answering questions about the predictability and repeatability of evolutionary adaptation. Here we theoretically investigate accessibility of the globally optimal state on a wide variety of model landscapes, including landscapes with tunable ruggedness as well as neutral `holey' landscapes. We define a mutational pathway to be accessible if it contains the minimal number of mutations required to reach the target genotype, and if fitness increases in each mutational step. Under this definition accessibility is high, in the sense that at least one accessible pathwayexists with a substantial probability that approaches unity as the dimensionality of the fitness landscape (set by the number of mutational loci) becomes large. At the same time the number of alternative accessible pathways grows without bound. We test the model predictions against an empirical 8-locus fitness landscape obtained for the filamentous fungus \textit{Aspergillus niger}. By analyzing subgraphs of the full landscape containing different subsets of mutations, we are able to probe the mutational distance scale in the empirical data. The predicted effect of high accessibility is supported by the empirical data and very robust, which we argue to reflect the generic topology of sequence spaces.Comment: 16 pages, 4 figures; supplementary material available on reques

Spatial Complex Network Analysis and Accessibility Indicators: the Case of Municipal Commuting in Sardinia, Italy

In this paper a contribution is presented with respect to accessibility indicators modelling for commuters moving through the municipalities of Sardinia, in Italy. In this case, spatial complex network analysis is integrated into the construction of accessibility measures: one of the most relevant outcomes of the first tool –the detection of shortest road paths and distances- is adopted as an input for the second in modelling accessibility indicators. Instead of Euclidean distances often adopted in the literature, shortest road distances are chosen, as commuting implies movements that are usually repeated daily and very likely subjected, even unconsciously, to space and time minimization strategies. In particular, two commuter accessibility indicators are constructed according to approaches based on a travel cost and a spatial interaction model with impedance function calibrated in exponential and in power form. The accessibility indicators are confronted each other and with relevant socio-economic and infrastructure characteristics of Sardinia. In addition, they are described, with respect to their spatial distribution and their different implications, when adopted in decision-making and planning. The travel cost based accessibility indicator has a municipal spatial distribution strongly influenced by the main road infrastructure of the Island. By contrast, spatial interaction model based accessibility indicators are more reliable, with respect to their capacity to confirm a leading socio-economic role of the municipalities comprehended in the metropolitan area of the capital town Cagliari

The case of public transport infrastructure in Malta, and its impact on the elderly

The concept of equity is essential in transport because inequities lead to the formation of transport-disadvantaged groups, such as the elderly, disabled and low-income people. This paper focuses on the elderly. Due to age-related circumstances, several elderly persons have to surrender on driving, consequently they become highly dependent on public transport. Hence, accessible public transport is crucial to provide them with the necessary mobility. This research considers accessibility as a key indicator for transport equity, since the latter primarily deals with the provision of equal access to opportunities. The study focuses on the case of Malta's public transport system, which is composed of the bus service. The uniqueness of the Maltese case is that transport policy is fragmented, and is not focused on equity. This paper looks at three aspects of accessibility related to road infrastructure, public transport infrastructure, and the bus fleet. The first aspect refers to accessibility at the macro scale, for instance, pavements may not be solely designed to cater for the bus service, but they are an integrative part of it. The meso scale refers to accessibility of infrastructure in physical and cyber form, such as access to and on bus stops and access to online travel information. The bus fleet refers to the micro scale of accessibility, which may include boarding and alighting the vehicle, and access on the vehicle. The research approach involves a review of existing Maltese public transport policy, with speci c focus on whether accessibility for the elderly is considered in the context of the afore-mentioned scales. It is envisaged that the minimal or non-existent policy on accessibility in public transport that focuses on elderly, makes this population segment at a double disadvantage. The research concludes with implications for policy related to public transport accessibility in a Maltese ageing society.peer-reviewe