Reproducibility and speed of landmarking process in cephalometric analysis using two input devices: mouse-driven cursor versus pen

To define if the new portable appliances, like smartphone, iPad, small laptop and tablet can be used in cephalometric tracing without dropping out the validity of any measurement. METHODS:We investigated and compared the reproducibility and the speed of landmarks identification process on lateral X-rays in two input devices: a mouse-driven cursor and a pen used as input means in mobile devices. One expert located 22 landmarks on 15 lateral X-rays in a repeated measure design two times, at time T1 and T2, after at least one month. The Intraclass Correlation coefficient was used to evaluate the reproducibility for each landmark tracing and the agreement between the value derived from both input devices. Also, the mean errors in measurements, the standard deviation and the Friedman Test significans (P < 0.05) between both input were statistically evaluated. RESULTS:All landmarks had a high agreement and the Friedman Test indicated statistically significant differences (P<0.05) for the identification of Na, Po, Pt, PNS, Ba, Pg, Gn, UIE, UIA, APOcc and PPOcc landmarks. CONCLUSIONS:Even if the mouse input give higher agreement for landmark tracing the differences are really minimal and they can be ignored in private practice. We suggest the adequacy of pen input in clinical setting

An investigation into alternative human-computer interaction in relation to ergonomics for gesture interface design

Recent, innovative developments in the field of gesture interfaces as input techniques have the potential to provide a basic, lower-cost, point-and-click function for graphic user interfaces (GUIs). Since these gesture interfaces are not yet widely used, indeed no tilt-based gesture interface is currently on the market, there is neither an international standard for the testing procedure nor a guideline for their ergonomic design and development. Hence, the research area demands more design case studies on a practical basis. The purpose of the research is to investigate the design factors of gesture interfaces for the point-andclick task in the desktop computer environment. The key function of gesture interfaces is to transfer the specific body movement into the cursor movement on the two-dimensional graphical user interface(2D GUI) on a real-time basis, based in particular on the arm movement. The initial literature review identified limitations related to the cursor movement behaviour with gesture interfaces. Since the cursor movement is the machine output of the gesture interfaces that need to be designed, a new accuracy measure based on the calculation of the cursor movement distance and an associated model was then proposed in order to validate the continuous cursor movement. Furthermore, a design guideline with detailed design requirements and specifications for the tilt-based gesture interfaces was suggested. In order to collect the human performance data and the cursor movement distance, a graphical measurement platform was designed and validated with the ordinary mouse. Since there are typically two types of gesture interface, i.e. the sweep-based and the tilt-based, and no commercial tilt-based gesture interface has yet been developed, a commercial sweep-based gesture interface, namely the P5 Glove, was studied and the causes and effects of the discrete cursor movement on the usability was investigated. According to the proposed design guideline, two versions of the tilt-based gesture 3 interface were designed and validated based on an iterative design process. Most of the phenomena and results from the trials undertaken, which are inter-related, were analyzed and discussed. The research has contributed new knowledge through design improvement of tilt-based gesture interfaces and the improvement of the discrete cursor movement by elimination of the manual error compensation. This research reveals that there is a relation between the cursor movement behaviour and the adjusted R 2 for the prediction of the movement time across models expanded from Fitts’ Law. In such a situation, the actual working area and the joint ranges are lengthy and appreciably different from those that had been planned. Further studies are suggested. The research was associated with the University Alliance Scheme technically supported by Freescale Semiconductor Co., U.S

The benefits of using a walking interface to navigate virtual environments

Navigation is the most common interactive task performed in three-dimensional virtual environments (VEs), but it is also a task that users often find difficult. We investigated how body-based information about the translational and rotational components of movement helped participants to perform a navigational search task (finding targets hidden inside boxes in a room-sized space). When participants physically walked around the VE while viewing it on a head-mounted display (HMD), they then performed 90&percnt; of trials perfectly, comparable to participants who had performed an equivalent task in the real world during a previous study. By contrast, participants performed less than 50&percnt; of trials perfectly if they used a tethered HMD (move by physically turning but pressing a button to translate) or a desktop display (no body-based information). This is the most complex navigational task in which a real-world level of performance has been achieved in a VE. Behavioral data indicates that both translational and rotational body-based information are required to accurately update one's position during navigation, and participants who walked tended to avoid obstacles, even though collision detection was not implemented and feedback not provided. A walking interface would bring immediate benefits to a number of VE applications

Vibrotactile Guidance Cues For Target Identification

The purpose of this dissertation was to establish how vibrotactile guidance cues can be used to improve marksmanship. This work originated in an effort to provide covert communication, navigation, and weapon aiming cues for infantrymen. It is predominantly an application-driven investigation rather than driven a priori by specific theoretical predictions from models of human performance. Three experiments are presented. Experiment 1 established the affect on initial response to vibrotactile guidance cues of tactor placements on the palmer versus dorsal surface of the hand, and targets appearing left versus right of center. Results suggest that tactile cues provided on the left side of the medial line of the hand afford moving the hand to the left, while tactile cues provided on the right side of the medial line afford moving the hand to the right. Experiment 2 established the affect of continuous relative distance cues and on- versus off-target vibrotactile stimuli on reaction time and accuracy for target selection. Results indicated an interaction between the pulse rate of vibrotactile stimuli and the method used to highlight an on-target condition; the suppressed target condition was superior to the enhanced target condition when the pulse rate increased as the cursor moved closer to a target. Experiment 3 established if there are performance differences between discrete and continuous distance information for target selection, and investigated the interaction between the near-target pulse rate and on-target cues. Results indicate that maximizing the difference between near-target guidance cues and on-target cues reduces the target selection time, particularly when the near-target pulse rates are fast (ISI = 10 msec). The results also suggest that, as with vision, the vibrotactile off-target guidance cues are not necessary during the whole target selection task. Rather, the guidance cues can be provided only during the initial pop-up condition and during the sub-movements closing on the target

IDENTIFYING PREFERENCES THROUGH MOUSE CURSOR MOVEMENTS – PRELIMINARY EVIDENCE

Identifying customers’ preferences is a challenging task with significant practical implications for online shopping. Current methods often put considerable burden on the customers through such methods as questioning, so the process could benefit from a more accurate and less intrusive estimation of how customers weight product attributes, particularly in the initial purchasing phase. Our goal is to derive attribute weights automatically by recording and analyzing cursor movements. We conducted an experiment to confirm the suitability of the proposed design, and found a highly significant correlation between the time people spend investigating a product attribute and their self-reported importance rating. Our proposed Web page design might also reduce the risk of information overload

Multidimensional Approach to Implicit Bias and the Underlying Cognitive Mechanism

abstract: Social categories such as race and gender are associated by people with certain characteristics (e.g. males are angry), which unconsciously affects how people evaluate and react to a person of specific social categories. This phenomenon, referred to as implicit bias, has been the interest of many social psychologists. However, the implicit bias research has been focusing on only one social category at a time, despite humans being entities of multiple social categories. The research also neglects the behavioral contexts in which implicit biases are triggered and rely on a broad definition for the locus of the bias regulation mechanism. These limitations raise questions on whether the current bias reduction strategies are effective. The current dissertation sought to address these limitations by introducing an ecologically valid and multidimensional method. In Chapters 1 and 2, the mouse-tracking task was integrated into the implicit association task to examine how implicit biases were moderated in different behavioral contexts. The results demonstrated that the manifestation of implicit biases depended on the behavioral context as well as the distinctive identity created by the combinations of different social categories. Chapter 3 laid groundwork for testing working memory as the processing capacity for the bias regulation mechanism. The result suggested that the hand-motion tracking indices of working memory load could be used to infer the capacity of an individual to suppress the influence of implicit bias. In Chapter 4, the mouse-tracking paradigm was integrated into the Stroop task with implicit associations serving as the Stroop targets. The implicit associations produced various effects including the conflict adaptation effect, like the Stroop targets, which suggested that implicit associations and Stroop stimuli are handled by overlapping cognitive mechanisms. Throughout these efforts, the current dissertation, first, demonstrated that a more ecologically valid and multidimensional approach is required to understand biased behaviors in detail. Furthermore, the current dissertation suggested the cognitive control mechanism as a finer definition for the locus of the bias regulation mechanism, which could be leveraged to offer solutions that are more adaptive and effective in the environment where collaboration and harmony are more important than ever.Dissertation/ThesisDoctoral Dissertation Human Systems Engineering 201

Investigating the Effect of Insurance Fraud on Mouse Usage in Human-Computer Interactions

The completion of online forms is the catalyst for many business and governmental processes. However, providing fraudulent information in such forms is pervasive, resulting in costly consequences for organizations and society. Furthermore, detecting fraudulent responses in online forms is often very difficult, time consuming, and expensive. This research proposes that analyzing users’ mouse movements may reveal when a person is being fraudulent. Namely, based on neuroscience and deception theory, the paper explains how deception may influence hand movements captured via the computer mouse. In an insurance fraud context, a study is conducted to explore these proposed relationships. The results suggest that being deceptive may increase the normalized distance of movement, decrease the speed of movement, increase the response time, and result in more left clicks. Implications for human-computer interaction research and practice are discussed