Notebook input devices put to the age test: the usability of trackpoint and touchpad for middle-aged adults

In two experiments, the usability of input devices integrated into computer notebooks was under study. The most common input devices, touchpad (experiment 1) and trackpoint (experiment 2) were examined. So far, the evaluation of mobile input devices has been restricted to younger users. However, due to ongoing demographic change, the main target group of mobile devices will be older users. Therefore, the present study focused on ageing effects. A total of 14 middle-aged (40–65 years) and 20 younger (20–32 years) users were compared regarding speed and accuracy of cursor control in a point-click and a point-drag-drop task. Moreover, the effects of training were addressed by examining the performance increase over time. In total, 640 trials per task and input device were executed. The results show that ageing is a central factor to be considered in input device design. Middle-aged users were significantly slower than younger users when executing the different tasks. Over time, a significant training effect was observed for both devices and both age groups, although the benefit of training was greater for the middle-aged group. Generally, the touchpad performance was higher than the trackpoint performance in both age groups, but the age-related performance decrements were less distinct when using the touchpad.     

Sensumotor transformation of input devices and the impact on practice and task difficulty

In the present study, the usability of two laptop input devices, touchpad and trackpoint, is evaluated. The focus is set on the impact of sensumotor transformation of input devices on practice and task difficulty. Thirty novices and 14 experts operated either touchpad or trackpoint over a period of 1600 trials of a point-click task. As hypothesized, novices and experts operated the touchpad by 15% faster compared to the trackpoint. For novices, performance rose distinctly and levelled off after 960 trials. This consolidation occurred earlier than reported in literature (1400–1600 trials) and, contrary to the assumption, learning was similar for touchpad and trackpoint. The impact of task difficulty dropped remarkably by practice, which points at a more general than specific task learning. In conclusion, ergonomic guidelines can be derived for the user-specific optimization of the usage of touchpad and trackpoint. Actual and potential applications of this research include the user-specific optimization of laptop input devices. Within the theoretical framework of psychomotor models, a profound knowledge of user behaviour in human – computer interaction is provided. Ergonomic guidelines can be derived for the efficient usage of laptop input devices and an optimized hardware and software design.     

Sensumotor transformation of input devices and the impact on practice and task difficulty

In the present study, the usability of two laptop input devices, touchpad and trackpoint, is evaluated. The focus is set on the impact of sensumotor transformation of input devices on practice and task difficulty. Thirty novices and 14 experts operated either touchpad or trackpoint over a period of 1600 trials of a point-click task. As hypothesized, novices and experts operated the touchpad by 15% faster compared to the trackpoint. For novices, performance rose distinctly and levelled off after 960 trials. This consolidation occurred earlier than reported in literature (1400-1600 trials) and, contrary to the assumption, learning was similar for touchpad and trackpoint. The impact of task difficulty dropped remarkably by practice, which points at a more general than specific task learning. In conclusion, ergonomic guidelines can be derived for the user-specific optimization of the usage of touchpad and trackpoint. Actual and potential applications of this research include the user-specific optimization of laptop input devices. Within the theoretical framework of psychomotor models, a profound knowledge of user behaviour in human-computer interaction is provided. Ergonomic guidelines can be derived for the efficient usage of laptop input devices and an optimized hardware and software design.     

Touch a screen or turn a knob: choosing the best device for the job

Input devices enable users to interact with systems. In two experiments, we assessed whether and how task demands and user age influenced task performance for a direct input device (touch screen) and an indirect input device (rotary encoder). In Experiment 1, 40 younger (18-28 years) and 40 middle-aged to older adults (51-65 years) performed tasks using controls such as sliders, up/down buttons, list boxes, and text boxes while using a system. The optimal input device to facilitate performance was dependent on the task being performed and the age of the user. In Experiment 2, touch screen use was assessed for 20 younger (19-23 years) and 20 older adults (51-70 years). Task demands were manipulated through button size, movement distance, direction, and type of movement. Performance was moderated by the age of the user and by task demands. Actual or potential applications of this research include guidance for the optimal selection of input devices for different user populations and task characteristics.     

Interacting with notebook input devices: an analysis of motor performance and users' expertise

In the present study the usability of two different types of notebook input devices was examined. The independent variables were input device (touchpad vs. mini-joystick) and user expertise (expert vs. novice state). There were 30 participants, of whom 15 were touchpad experts and the other 15 were mini-joystick experts. The experimental tasks were a point-click task (Experiment 1) and a point-drag-drop task (Experiment 2). Dependent variables were the time and accuracy of cursor control. To assess carryover effects, we had the participants complete both experiments, using not only the input device for which they were experts but also the device for which they were novices. Results showed the touchpad performance to be clearly superior to mini-joystick performance. Overall, experts showed better performance than did novices. The significant interaction of input device and expertise showed that the use of an unknown device is difficult, but only for touchpad experts, who were remarkably slower and less accurate when using a mini-joystick. Actual and potential applications of this research include an evaluation of current notebook input devices. The outcomes allow ergonomic guidelines to be derived for optimized usage and design of the mini-joystick and touchpad devices.     

Practice and carryover effects when using small interaction devices

The use of interaction devices in modern work often challenges the human motor system, especially when these devices introduce unfamiliar transformations to the user. In this paper we evaluated expert performance and skill differences between experts and novices when using small motion- and force-controlled interaction devices (touchpad and mini-joystick) in an applied text-editing task. Firstly, experts performed better with their familiar input device than with an unfamiliar one. Particularly touchpad experts operating the unfamiliar mini-joystick showed highly asymmetric carryover costs. Results showed that the efficient performance of experts depended on domain-specific skills, which were not transferable. Secondly, with considerable practice (more than observed for simple and short tasks) novices were brought up to higher levels of performance. The motion-transformation between hand and cursor action was easier in understanding and application than the force-transformation. Thus, the touchpad was used more efficiently than the mini-joystick. In conclusion, practice effects found so far are considerably underestimated when it comes to an applied task. The results give reason to develop and implement skill-sensitive training procedures, since the acquisition of domain-specific skills is critical for expert performance. As a consequence, training procedures might be essential for complex applications and/or unfamiliar device transformations.     

Light pen use and practice minimize age and hand performance differences in pointing tasks

We contrasted performance with mouse and light pen input devices for younger, middle-aged, and older adults (N = 72) who were experienced mouse users. Participants used both preferred and nonpreferred hands to perform a menu target selection task. The light pen minimized age differences in performance relative to the mouse. Older adults were more lateralized on a handedness test than young adults and were less efficient using their nonpreferred hand. With practice, older adults improved their response time more than other age groups did. The mouse was rated as more acceptable and easier to use than the light pen across trials, despite the performance advantage of the light pen for all age groups. Usability ratings correlated moderately with performance. A benefit-cost analysis indicated that the more efficient light pen might cover its greater initial cost within 11 months for an older adult and within 23 months for a younger adult. Actual or potential applications of this research include advising older adults to persist with practice for new input devices, advising those who must switch to their non-preferred hand to select a direct positioning device, and providing a methodology for determining the potential payback interval when switching to a faster, though more expensive, input device.     

Evaluation of Text Entry Methods for Interactive Digital Television Applications with Devices Alternative to Conventional Remote Controls

The popularity of Interactive Digital Television (IDTV) applications has grown in recent years, playing a significant role in today’s society. This new type of television allows users to access interactive applications in order to look for information, for communication or educational purposes, or just for fun. Most of these applications require text entry and many users expect a user experience similar to that of computers. Although the most common device to interact with television is the conventional remote control, other devices available on the market may be used in this context. Thus, in this article we aim to evaluate and compare different text input methods for IDTV applications using devices alternative to conventional remote controls. We have carried out an empirical study with 52 participants. We analyze entry speeds, error rates, and subjective impressions for six different entry methods, taking into account the particular characteristics of the users. As devices we have used a full-sized keyboard, a palm-sized keyboard, a gyroscopic remote point-select, and a modified touchpad. The fastest method is the standard keyboard, but in an IDTV context many users report discomfort and problems under low lighting conditions. Also, error rates are considerably higher with both keyboards when modifier keys need to be used. The results obtained with the gyroscopic remote and the touchpad are similar. Nevertheless, while users complain about fatigue problems with the former, their feedback about the latter is very positive. We have also observed that age is a major factor affecting the performance of the users. We expect our results to contribute to the design of new text entry methods for IDTV.     

Input devices for web browsing: age and hand effects

The work reported in this paper examined performance on a mixed pointing and data entry task using direct and indirect positioning devices for younger, middle-aged, and older adults (n=72) who were experienced mouse users. Participants used both preferred and non-preferred hands to perform an item selection and text entry task simulating a typical web page interaction. Older adults performed more slowly than middle-aged adults who in turn performed more slowly than young adults. Performance efficiency was superior with the mouse for older adults only on the first two trial blocks. Thereafter mouse and light pen yielded equivalent performance. For other age groups, mouse and light pen were equivalent at all points of practice. Contrary to prior research revealing superior performance with a light pen for pure pointing tasks, these results suggest that older adults may initially perform worse with a light pen than a mouse for mixed tasks.     

Designing touchpad user-interfaces for vehicles: which tasks are most suitable?

Designers of in-vehicle computing systems must consider which input devices are most suitable for use in the safety-critical driving situation. This paper describes a study aiming to establish which tasks are best supported by an in-vehicle touchpad system. Eighteen participants (50:50 right/left handed) drove three routes in a right-hand drive simulator while following a lead vehicle at a perceived safe distance. At specific points, participants were asked to carry out seven tasks of varying qualities using a prototype touchpad system, a touchscreen or a rotary controller interface. Results indicated that participants were most negative (in terms of preferences and performance) with the rotary controller interface. Conversely, the results for the touchpad versus the touchscreen interfaces were clearly task dependent. For instance, with the touchpad, subjective opinions and objective performance were most positive for tasks in which simple commands enabled drivers to bypass the need for complex menu interactions (e.g. changing the interior temperature). In contrast, results for the touchscreen were evidently superior for simple menu selection tasks (e.g. selecting a preset radio station). Conclusions are drawn regarding the nature of tasks that are best suited to alternative input devices within vehicles and the potential for a touchpad/touchscreen solution.     

Effectiveness of hand- and foot-operated secondary input devices for word-processing tasks before and after training

Previous research has shown that, without practice, users are slower using the foot than the hand to control input devices. This study compared the performance (before and after practice) of users operating a foot-controlled secondary input device (foot mouse) with the performance of users operating a hand-controlled secondary input device (hand trackball) to complete four word-processing tasks requiring various amounts of keyboard and secondary input device use. Before practice, hand trackball performance was better on all tasks. After practice, hand trackball performance was better on all tasks except the task requiring the greatest amount of keyboard use, for which there was no significant difference between devices. For all tasks, practice improved performance with the foot mouse but not with the hand trackball. These findings suggest that, with enough practice, it may be efficient for users to use a foot input device for tasks that also require keyboard input.     

Book Review

In this experiment, older and younger novice mobile phone users were examined when using handsets of different complexity. The independent variables were user age (young: 20 – 35 years; old: 50 – 64 years) and cognitive complexity of two mobile phones (Nokia 3210; Siemens C35i). The cognitive complexity of the phones was defined by the number of production rules applied when processing the four experimental tasks. Dependent variables were effectiveness and efficiency as taken from user protocols and the reported ease of use. The less complex phone (Nokia) performed significantly better than the complex one (Siemens). However, the benefit from the lower complexity was much larger than theoretically predicted. Thus, defining cognitive complexity of technical devices by the number of production rules does not account for the real difficulties which users experience. Older users had a lower navigation performance than younger users, however their performance matched younger users' when using mobiles with low complexity.     

Using non-keyboard input devices: interviews with users in the workplace

A study of 45 non-keyboard input device (NKID) users was undertaken at nine organisations to investigate the extent, pattern and method of NKID usage, workstation configurations, postures adopted and musculoskeletal symptoms. A number of methods were used: work activity diaries, interviews, observations and postural assessments. A range of NKID were seen including the mouse, touchscreen, joystick, trackball, and tablet and pen; however, the mouse was the most commonly used device. Use of an input device varied from 2% to 100% of the working day. Workers undertook common tasks using a variety of methods (e.g. pull down menus, icons, device buttons). Users reported problems associated with the use of some devices, e.g. poor maintenance, lack of device responsiveness. Musculoskeletal pain and discomfort (e.g. stiffness and discomfort in the hands and wrist) was reported by 45% (n=19) of mouse users and 16% (n=5) of other NKID users. Workstation configurations varied and in some cases constrained the position of the input device, resulting in users having to work with the device at some distance away from the body. Despite the existence of regulations and guidance, this paper indicates that there are still many problems related to NKID use at computer workstations.

Relevance to industry

The reliance of many software applications on NKID (e.g. mouse, trackball, touchpad, joystick, touchscreen) necessitates the investigation of their use in the workplace. Whilst the performance aspects of NKID (e.g. speed) have been well researched, the possible implications for user health have received little attention in the UK.     

Effects of Chinese character size,number of characters per line,and number of menu items on visual search task on tablet computer displays for different age groups

The goal of this study was to investigate the effects of Chinese character size, number of characters per line, and number of menu items on visual search task performance on a tablet computer for different age group users. Forty-two participants participated the visual search experiment. Gender, age group (younger, middle-aged, and older), Chinese character size (15, 17, 19, 21, 23, and 25 point), number of characters per line (2–5 characters, 9–14 characters, and 15–18 characters), and number of menu items (5, 7, 9, 11, and 13 items) were the independent variables. The dependent variables included search time and error rate. Gender had a large effect size on search time. Female participants had a faster search time than male participants. Significant differences and large effect sizes were found in search performance for different character sizes, number of characters per line, and number of menu items. Nine to fourteen characters per line achieved the fastest search time and lowest error rate. The fastest search time was for a 19-point character size in the younger group; 21-point character size in the middle-aged group; and 23-point character size in the older group. Besides, the fastest search time was found when showing 9 items in the younger group; 7 items in the middle-aged group; and 5 items in the older group. The optimum visual search performance was achieved with 19-point character size showing 9 items and 9–14 characters per line for the younger group; 21-point character size showing 7 items and 9–14 characters per line for the middle-aged group; and 23-point character size showing 5 items and 9–14 characters per line for the older group. The results provide useful information for tablet computer interface-presentations for different age group users.     

Effects of Laptop Touchpad Texturing on User Performance

This research assessed user performance with different laptop touchpad textures. In specific, the study measured discrete movement task time and accuracy. It was hypothesized that texturing would increase task times but improve accuracy by providing users with tactile references. A variable representing the frictional potential of pads was introduced into an established model of discrete movement performance (Fitts’ Law) in an attempt to accurately model user performance under experimental task conditions. Results revealed touchpad texturing to degrade task performance. However, accuracy in pointing tasks was not significantly affected. Results also revealed that the expanded form of Fitts’ Law, including a parameter for representing the frictional potential of pad texturing, was more predictive of actual movement times than the original form of the Law. Results from the study increase understanding of the effects of touchpad texture on human motor control behavior and provide some guidance for future pad design.     

Effects of age, speech rate, and environmental support in using telephone voice menu systems

Age differences in the use of telephone menu systems were investigated in two experiments. Participants from three age groups (younger: 18-39; middle-aged: 40-59; older: 60+ years) were required to obtain specified information or perform some action using simulated voice menu systems. Measures reflecting task performance, menu navigation, and subjective responses were collected. The focus in Experiment 1 was on examining the effect of speech rate. Data from 196 participants indicated age differences in performance, especially for complex problems. There was no effect of speech rate on any of the performance measures. Experiment 2 examined two types of support devices: a screen phone and a graphical aid. Data from 114 participants indicated that the screen phone provided some benefits in navigational efficiency. In terms of performance, the older participants benefited more from the graphical aid and the younger participants performed better with the screen phone. Actual or potential applications of this research include guidance in the use of support devices that can reduce memory demands and the identification of appropriate speech rates.     

Ubiquitous learning website: Scaffold learners by mobile devices with information-aware techniques

The portability and immediate communication properties of mobile devices influence the learning processes in interacting with peers, accessing resources and transferring data. For example, the short message and browsing functions in a cell phone provide users with timely and adaptive information access. Although many studies of mobile learning indicate the pedagogical potential of mobile devices, the screen size, computational power, battery capacity, input interfaces, and network bandwidth are too restricted to develop acceptable functionality for the entire learning processes in a handheld device. Therefore, mobile devices can be adopted to fill the gap between Web-based learning and ubiquitous mobile learning. This study first creates a website, providing functions enabling learning to take place anytime and anywhere with any available learning device, for ubiquitous learning according to various properties of mobile devices. Nowadays, learners’ behaviors on a website can be recorded as learning portfolios and analyzed for behavioral diagnosis or instructional planning. A student model is then built according to the analytical results of learning portfolios and a concept map of the learning domain. Based on the student model and learners’ available learning devices, three modules are developed to build a ubiquitous learning environment to enhance learning performance via learning status awareness, schedule reminders and mentor recommendation. Finally, an experiment is conducted with 54 college students after implementation of the ubiquitous learning website. Experimental results indicate that the proposed system can enhance three learning performance indicators, namely academic performance, task accomplishment rates, and learning goals achievement rates.     

Mobile text-entry and visual demands: reusing and optimizing current solutions

Mobile devices are increasingly used for text-entry in contexts where visual attention is fragmented and graphical information is inadequate, yet the current solutions to typing on virtual keyboards make it a visually demanding task. This work looks at assistive technologies and interface attributes as tools to ease the task. Two within-subject experiments were performed with 23 and 17 participants, respectively. The first experiment aimed to understand how walking affected text-entry performance and additionally to assess how effective assistive technologies can be in mobile contexts. In the second experiment, adaptive keyboards featuring character prediction and pre-attentive attributes to ease visual demands of text-entry interfaces were developed and evaluated. It has been found that both text-input speed and overall quality are affected in mobile situations. Contrary to the expectations, assistive technologies proved ineffective with visual feedback. The second experiment showed that pre-attentive attributes do not affect users’ performance in task-entry tasks, even though a 3.3–4.3 % decrease in error rates was measured. It was found that users reduce walking speed to compensate for challenges placed by mobile text-entry. Caution should be exercised when transferring assistive technologies to mobile contexts, since they need adaptations to address mobile users’ needs. Also, while pre-attentive attributes seemingly have no effect on experienced QWERTY typists’ performance, they showed promise for both novice users and typists in attention-demanding contexts.     

Designing touchpad user-interfaces for right-hand drive vehicles: an investigation into where the touchpad should be located

Touchpads in vehicles offer a range of potential benefits over existing input devices, such as touchscreens. This article describes a study aiming to establish where a touchpad should be located within a right-hand drive vehicle. Sixteen participants (50:50 right/left handed) drove three routes in a right-hand drive simulator while following a lead vehicle at a perceived safe distance. At specific points, participants were asked to carry out three tasks of varying complexity using the touchpad. For each of the routes travelled, the touchpad was positioned in one of the three locations: in the centre console; in the door armrest and in the steering wheel. Differences in the performance and preferences of right-handed people vs. left-handed people were found. Right-handed people rated the door armrest location highly and made few glances towards this location while driving. In contrast, left-handed drivers were more positive towards the centre console location. The steering wheel location required a particularly high-visual demand. It is concluded that, for right-hand drive vehicles, a touchpad should be located in both the centre console and the door armrest to suit the diverse needs of the driver population.     

A usability study on human–computer interface for middle-aged learners

“Usability” is considered to be inherent in human–computer interface because it expresses the relationship between end users and computer applications. In this paper, we conducted a study to examine the usability of human–computer interface for middle-aged learners in Taiwan. There are two phases contained in the study: (1) an elementary computer-training task, and (2) a usability analysis of human–computer interface. Making use of a questionnaire survey, correlation analysis, and the grey relational model, some user characteristics and learning behavior were derived. For example, regarding middle-aged learners, the usability of present mouse and monitor devices is preferable to that of the keyboard device and a Windows-based software interface. Educational level is the major factor influencing middle-aged learners’ use of computer interfaces. To unemployed middle-aged learners, more males than females were found to exhibit the phenomenon of computerphobia. The younger age learners show lower anxiety and hold more positive attitudes toward computer learning than the older-aged ones. Besides, the higher education learners hold much more positive expectation toward computer learning while the lower education learners pay more attention to their learning capability and deficiency.