Hitts Law? A test of the relationship between information load and movement precision

Recent technological developments have made viable a man-machine interface heavily dependent on graphics and pointing devices. This has led to new interest in classical reaction and movement time work by Human Factors specialists. Two experiments were designed and run to test the dependence of target capture time on information load (Hitt's Law) and movement precision (Fitts' Law). The proposed model linearly combines Hitt's and Fitts' results into a combination law which then might be called Hitts' Law. Subjects were required to react to stimuli by manipulating a joystick so as to cause a cursor to capture a target on a CRT screen. Response entropy and the relative precision of the capture movement were crossed in a factorial design and data obtained that were found to support the model

Visual Attention to Radar Displays

A model is described which predicts the allocation of attention to the features of a radar display. It uses the growth of uncertainty and the probability of near collision to call the eye to a feature of the display. The main source of uncertainty is forgetting following a fixation, which is modelled as a two dimensional diffusion process. The model was used to predict information overload in intercept controllers, and preliminary validation obtained by recording eye movements of intercept controllers in simulated and live (practice) interception

Designing Leadership Development Program Curriculum: A Narrative Research Study

A high priority is placed on developing leadership skills because of its importance to organizational performance and growth. Since 2010, significant investment has been put into leadership programs by companies globally with the goal of producing more effective leaders. Despite the expenditure into leadership development, most training efforts fail to meet learners’ needs because they do not include participant perspectives in the content decision-making process, using outdated leadership theories as a framework for content development, or failing to evaluate training efforts. These failures result in a mismatch between the challenges leaders face in their roles and the content of a leadership program. Therefore, to successfully design programs that meet learners’ needs, an understanding of an audience’s challenges is critical. The purpose of this qualitative study was to understand the challenges leaders face in a global technology company. In this study, the researcher specifically used narrative inquiry to understand the stories of past participants in a leadership development program. The researcher collected data by retrospective analyses of open-ended internal surveys gathered by the study organization during the last 12 months for the purposes of identifying challenges leaders face in their leadership roles and understanding perceptions of how well a leadership program prepared them to respond to these challenges. The researcher intends the findings to help the organization identify to what extent the content of their current leadership program addressed the challenges of the participants

Cost-effectiveness of long-acting reversible contraceptive methods: a review

Long-acting reversible contraception (LARC) methods are proven to be effective in preventing unintended pregnancies. Evidence on cost-effectiveness of these methods will enable policy makers to introduce them in national policies and programs to improve contraceptive access. The aim was to review the studies based on economic evaluations of LARC methods and provide evidence to policy makers to renew their commitment to family planning access. A review of studies on economic evaluations of LARC methods was done. This article uses data from three electronic databases: PubMed, Cochrane and Web of Science to examine whether LARC is cost-effective for clinical trials. The results are presented as a narrative review and summary tables. The literature search yielded 87 studies and 12 studies (five economic evaluations studies from USA) and (five studies from Europe while two studies were from low and middle-income countries) were included. Out of 12 papers, nine had multiple comparators; seven included female sterilization as a comparator, while two studies compared one individual LARC contraceptive method with an individual SARC method. All studies consistently showed that LARCs dominated all SARC (short acting reversible contraceptives) methods. Within LARC, copper IUD, LNG-IUS and implant were more cost-effective than DMPA. After a period of five years, female sterilization turned out to be more cost-effective than LARC methods. LARC methods are cost-effective as compared to SARC methods, especially after 1 year of use. Vasectomy is more cost-effective than LARC methods. Policy makers can consider the findings of this review to aid decision making in contraceptive method introduction or scale-up access

Development of advanced direct perception displays for nuclear power plants to enhance monitoring, control and fault management

Traditional Single-Sensor-Single Indicator (SSSI) displays are poorly matched to the cognitive abilities of operators, especially for large and complex systems. It is difficult for operators to monitor very large arrays of displays and controls, and to integrate the information displayed therein. In addition, standard operating procedures (SOPs) are bulky (running to many hundreds of pages) and difficult to use, and operators may become lost. For these reasons, and also because it is becoming increasingly difficult to find replacements for aging hardware components, there is a trend towards computerized graphical interfaces for nuclear power plants (NPPs). There is, however, little rational theory for display design in this domain. This report describes some recent theoretical developments and shows how to develop displays which will greatly reduce the cognitive load on the operator and allow the use of perceptual rather than cognitive mechanisms while using SON and to support state diagnosis and fault management. The report outlines the conceptual framework within which such a new approach could be developed, and provides an example of how the operating procedures for the start-up sequence of a NPP could be realized. A detailed description of a set of displays for a graphical interface for the SON of the feedwater system is provided as an example of how the proposed approach could be realized, and a general account of how it would fit into the overall start-up sequence is given. Examples of {open_quotes}direct perception{close_quotes} or {open_quotes}ecological{close_quotes} configural state space displays to support the use of the proposed direct manipulation SOP interface are provided, and also a critical discussion which identifies some difficulties which may be anticipated should the general approach herein advocated be adopted

WESTT (Workload, Error, Situational Awareness, Time and Teamwork): An analytical prototyping system for command and control

Modern developments in the use of information technology within command and control allow unprecedented scope for flexibility in the way teams deal with tasks. These developments, together with the increased recognition of the importance of knowledge management within teams present difficulties for the analyst in terms of evaluating the impacts of changes to task composition or team membership. In this paper an approach to this problem is presented that represents team behaviour in terms of three linked networks (representing task, social network structure and knowledge) within the integrative WESTT software tool. In addition, by automating analyses of workload and error based on the same data that generate the networks, WESTT allows the user to engage in the process of rapid and iterative “analytical prototyping”. For purposes of illustration an example of the use of this technique with regard to a simple tactical vignette is presented

Why Are People's Decisions Sometimes Worse with Computer Support?

In many applications of computerised decision support, a recognised source of undesired outcomes is operators' apparent over-reliance on automation. For instance, an operator may fail to react to a potentially dangerous situation because a computer fails to generate an alarm. However, the very use of terms like "over-reliance" betrays possible misunderstandings of these phenomena and their causes, which may lead to ineffective corrective action (e.g. training or procedures that do not counteract all the causes of the apparently "over-reliant" behaviour). We review relevant literature in the area of "automation bias" and describe the diverse mechanisms that may be involved in human errors when using computer support. We discuss these mechanisms, with reference to errors of omission when using "alerting systems", with the help of examples of novel counterintuitive findings we obtained from a case study in a health care application, as well as other examples from the literature

The thoughtful self

The relationship between a concept in the external world (e.g., the self), and its representation in cognition

Communications Biophysics

Contains research objectives and reports on two research projects.National Institutes of Health (Grant 2 PO1 GM-14941-01)Joint Services Electronics Programs (U. S. Army, U.S. Navy, and U.S. Air Force) under Contract DA 28-043-AMC-02536(E)National Aeronautics and Space Administration (Grant NsG-496)National Institutes of Health (Grant 2 RO1 NB-05462-04)National Institutes of Health (Grant 1 TO1 GM-01555-01

Visual perceptual load induces inattentional deafness

In this article, we establish a new phenomenon of “inattentional deafness” and highlight the level of load on visual attention as a critical determinant of this phenomenon. In three experiments, we modified an inattentional blindness paradigm to assess inattentional deafness. Participants made either a low- or high-load visual discrimination concerning a cross shape (respectively, a discrimination of line color or of line length with a subtle length difference). A brief pure tone was presented simultaneously with the visual task display on a final trial. Failures to notice the presence of this tone (i.e., inattentional deafness) reached a rate of 79% in the high-visual-load condition, significantly more than in the low-load condition. These findings establish the phenomenon of inattentional deafness under visual load, thereby extending the load theory of attention (e.g., Lavie, Journal of Experimental Psychology. Human Perception and Performance, 25, 596–616, 1995) to address the cross-modal effects of visual perceptual load