Abstract
In this paper it is presented a usability evaluation of an entertainment platform, well-known, YouTube. The main aim is to study how people with intellectual disabilities interact with the layout and uses their search field option. We intended to observe and analyze performance and satisfaction but also if the interface can give them autonomy on the search option. The results show that participants had a good experience with the interface, however cannot be autonomy with the search option.

Abstract
In recent years there has been a boom of different natural interaction paradigms, such as touch, tangible or gesture-based interfaces, that make better use of human's innate skills rather than imposing new learning processes. However, no work has been reported that systematically evaluates how these interfaces influence users' performance with regard to their level of digital literacy or even age. Furthermore, it is also important to understand the interaction paradigms' impact when performing basic operations, such as data selection, insertion and manipulation, and which interface could be the most efficient for each task. This paper reports the first step of an exploratory evaluation about the relationship between different interaction paradigms and specific target-audiences: dealing with a selection task. We conducted an experiment with 60 subjects to evaluate how different interfaces may influence the performance of specific groups of users. Four input modalities are evaluated in a selection task and results for these different user groups are reported in terms of performance, efficacy (error rate) and user preference. For each group of users, we determined there was a statistically significant difference between the mean time taken to complete the task in each interface. Also, the one input modality every user was accustomed with (the computer mouse) was the one that showed the most discrepancy regarding performance between the groups. We believe that this study raises new issues for future research. Copyright 2014 ACM.

Abstract
Navigation in virtual environments is important because it allows the exploration of the virtual worlds. This paper presents an objective performance evaluation (based on the Steering Law) of two types of navigation: natural (real walking) vs. not natural (gamepad). Steering Law was the objective performance metric chosen since it captures the relationship between the time to travel a path and the difficulty of that path. In addition to the performance, subjective metrics were also considered, namely the feeling of presence, cybersickness and user satisfaction. The participants had to complete a series of paths with different difficulty indices and the time that a participant took to go through each one was measured. Overall results show that navigation through real walking had better performance, presence, cybersickness, and satisfaction than the gamepad interface.

Abstract
Novel input modalities such as touch, tangibles or gestures try to exploit human's innate skills rather than imposing new learning processes. However, despite the recent boom of different natural interaction paradigms, it hasn't been systematically evaluated how these interfaces influence a user's performance or whether each interface could be more or less appropriate when it comes to: 1) different age groups; and 2) different basic operations, as data selection, insertion or manipulation. This work presents the first step of an exploratory evaluation about whether or not the users' performance is indeed influenced by the different interfaces. The key point is to understand how different interaction paradigms affect specific target-audiences (children, adults and older adults) when dealing with a selection task. 60 participants took part in this study to assess how different interfaces may influence the interaction of specific groups of users with regard to their age. Four input modalities were used to perform a selection task and the methodology was based on usability testing (speed, accuracy and user preference). The study suggests a statistically significant difference between mean selection times for each group of users, and also raises new issues regarding the "old" mouse input versus the "new" input modalities.

Abstract
The traditional attitude towards user interfaces has changed. The Post-WIMP era has brought about novel input modalities such as touch, tangibles or gestures that allow users to manipulate digital contents more intuitively. These novel input modalities make use of the users' innate skills instead of imposing the learning of new interaction techniques. Nonetheless, there has not been a systematic evaluation on how, or if, these interfaces influence the users' performance and/or preference: distinct interfaces may be more or less appropriate regarding different age groups, user profiles, contexts or type of tasks. This work is a preliminary evaluation on whether the users' efficiency is indeed influenced by different input modalities or age. We conducted a target acquisition performance evaluation with 60 subjects to understand how different input modalities influence the speed and accuracy of three specific age groups (children, young adults and older-adults) when dealing with a continuous selection task. Three input modalities were considered to perform the task (mouse, touch and gestures) and the methodology was based on Fitts' law, a target acquisition performance evaluation model. Overall, when comparing movement times amongst the three groups, there are significant differences between age groups regarding the index of performance. We believe our findings may show that indeed the type of input modality used and the user's age could affect one's performance.

Abstract
This paper presents a case study regarding the usability evaluation of navigation tasks by people with intellectual disabilities. The aim was to investigate the factors affecting usability, by comparing their user-Web interactions and underline the difficulties observed. For that purpose, two distinct study phases were performed: the first consisted in comparing interaction using two different search engines’ layouts (Google and SAPO) and the second phase consisted in a preliminary evaluation to analyze how users performed the tasks with the usual input devices (keyboard and mouse) and provide an alternative interface to help overcome possible interaction problems and enhance autonomy. For the latter, we compared two different interfaces: a WIMP-based one and speech-based one. The main results obtained showed that users had a better performance with Google (with a simpler layout) than with SAPO (with a complex layout), and despite displaying a good keyboard handling ability, they did not show autonomy using this input device (due to the need for reading/writing when handling this device). In this perspective, Google’s speech recognition application could indeed be considered an alternative for interaction. However, we found that the speech recognition interface is not as robust as it should be: it could be more precise and less prone to errors due to poor word pronunciation. After this two-phased study, we think we may be able to infer some recommendations to be used by developers in order to create more intuitive layouts for easy navigation regarding this group of people, and thereby facilitate digital inclusion. © 2016 Springer-Verlag Berlin Heidelberg