Luz Rello

Layout guidelines for web text and a web service to improve accessibility for dyslexics

In this paper, we offer set of guidelines and a web service that presents Web texts in a more more accessible way to people with dyslexia. The layout guidelines for developing this service are based on a user study with a group of twenty two dyslexic users. The data collected from our study combines qualitative data from interviews and questionnaires and quantitative data from tests carried out using eye tracking. We analyze and compare both kinds of data and present a set of layout guidelines for making the text Web more readable for dyslexic users. To the best of our knowledge, our methodology for defining dyslexic-friendly guidelines and our web service are novel.

Good fonts for dyslexia

Around 10% of the people have dyslexia, a neurological disability that impairs a persons ability to read and write. There is evidence that the presentation of the text has a significant effect on a texts accessibility for people with dyslexia. However, to the best of our knowledge, there are no experiments that objectively measure the impact of the font type on reading performance. In this paper, we present the first experiment that uses eye-tracking to measure the effect of font type on reading speed. Using a within-subject design, 48 subjects with dyslexia read 12 texts with 12 different fonts. Sans serif, monospaced and roman font styles significantly improved the reading performance over serif, proportional and italic fonts. On the basis of our results, we present a set of more accessible fonts for people with dyslexia.

Frequent Words Improve Readability and Short Words Improve Understandability for People with Dyslexia

Around 10% of the population has dyslexia, a reading disability that negatively affects a person’s ability to read and comprehend texts. Previous work has studied how to optimize the text layout, but adapting the text content has not received that much attention. In this paper, we present an eye-tracking study that investigates if people with dyslexia would benefit from content simplification. In an experiment with 46 people, 23 with dyslexia and 23 as a control group, we compare texts where words were substituted by shorter/longer and more/less frequent synonyms. Using more frequent words caused the participants with dyslexia to read significantly faster, while the use of shorter words caused them to understand the text better. Amongst the control group, no significant effects were found. These results provide evidence that people with dyslexia may benefit from interactive tools that perform lexical simplification.

Semantic Similarity of Distractors in Multiple-Choice Tests: Extrinsic Evaluation

Mitkov and Ha (2003) and Mitkov et al. (2006) offered an alternative to the lengthy and demanding activity of developing multiple-choice test items by proposing an NLP-based methodology for construction of test items from instructive texts such as textbook chapters and encyclopaedia entries. One of the interesting research questions which emerged during these projects was how better quality distractors could automatically be chosen. This paper reports the results of a study seeking to establish which similarity measures generate better quality distractors of multiple-choice tests. Similarity measures employed in the procedure of selection of distractors are collocation patterns, four different methods of WordNet-based semantic similarity (extended gloss overlap measure, Leacock and Chodorows, Jiang and Conraths as well as Lins measures), distributional similarity, phonetic similarity as well as a mixed strategy combining the aforementioned measures. The evaluation results show that the methods based on Lins measure and on the mixed strategy outperform the rest, albeit not in a statistically significant fashion.

Simplify or help?: text simplification strategies for people with dyslexia

We present a user study for two different automatic strategies that simplify text content for people with dyslexia. The strategies considered are the standard one (replacing a complex word with the most simpler synonym) and a new one that presents several synonyms for a complex word if the user requests them. We compare texts transformed by both strategies with the original text and to a gold standard manually built. The study was undertook by 96 participants, 47 with dyslexia plus a control group of 49 people without dyslexia. To show device independence, for the new strategy we used three different reading devices. Overall, participants with dyslexia found texts presented with the new strategy significantly more readable and comprehensible. To the best of our knowledge, this is the largest user study of its kind.

Size matters (spacing not): 18 points for a dyslexic-friendly Wikipedia

In 2012, Wikipedia was the sixth-most visited website on the Internet. Being one of the main repositories of knowledge, students from all over the world consult it. But, around 10% of these students have dyslexia, which impairs their access to text-based websites. How could Wikipedia be presented to be more readable for this target group? In an experiment with 28 participants with dyslexia, we compare reading speed, comprehension, and subjective readability for the font sizes 10, 12, 14, 18, 22, and 26 points, and line spacings 0.8, 1.0, 1.4, and 1.8. The results show that font size has a significant effect on the readability and the understandability of the text, while line spacing does not. On the basis of our results, we recommend using 18-point font size when designing web text for readers with dyslexia. Our results significantly differ from previous recommendations, presumably, because this is the first work to cover a wide range of values and to study them in the context of an actual website.

One Half or 50%? An Eye-Tracking Study of Number Representation Readability

Are numbers expressed as digits easier to read and understand than written with letters? What about fractions and percentages? Exact or rounded values? We present an eye-tracking study that attempts to answer these questions for Spanish, using fixation and reading time to measure readability as well as comprehension questions to score understandability. We find that digits are faster to read but do not help comprehension. Fractions help understandability while percentages help readability. No significant results were found concerning the influence of rounding. Our experiments were performed by 72 persons, half of them with dyslexia. To the best of our knowledge, this is the first study that addresses the cognitive load of number representation in any language, even more for people with dyslexia.

What is wrong with this word? dyseggxia: a game for children with dyslexia

We present Dyseggxia, a game application with word exercises for children with dyslexia. We design the content of the game combining linguistic and pedagogical criteria as well as corpus analysis. The main contributions are (i) designing exercises by using the analysis of errors written by people with dyslexia and (i) presenting Spanish reinforcement exercises in the form of a computer game. The game is available for free on iOS and Android.

Estimating dyslexia in the web

In this study we present an estimation of texts containing English dyslexic errors in the Web. A classification of lexical errors is proposed and unique dyslexic errors are distinguished from other kind of errors due to spelling and grammatical errors, typos, OCR errors and errors produced when English is used as a foreign language. A representative sample of each kind of error is used to calculate a lower bound for the prevalence of dyslexia in the English Web. Although dyslexia has been studied in the context of Web accessibility, to the best of our knowledge, an estimation of Web texts containing dyslexic errors was unknown. Our results are useful to tackle future work in Web accessibility among dyslexic users focusing not only in the interface but also in the text content.

Lexical quality as a proxy for web text understandability

We show that a recently introduced lexical quality measure is also valid to measure textual Web accessibility. Our measure estimates the lexical quality of a site based in the occurrence in English Web pages of a large set of words with errors. We first compute the correlation of our measure with Web popularity measures to show that gives independent information. Second, we carry out a user study using eye tracking to prove that the degree of lexical quality of a text is related to the degree of understandability of a text, one of the factors behind Web accessibility.