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% 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% 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

Effects of hyperlinks on navigation in virtual environments

Hyperlinks introduce discontinuities of movement to 3-D virtual environments (VEs). Nine independent attributes of hyperlinks are defined and their likely effects on navigation in VEs are discussed. Four experiments are described in which participants repeatedly navigated VEs that were either conventional (i.e. obeyed the laws of Euclidean space), or contained hyperlinks. Participants learned spatial knowledge slowly in both types of environment, echoing the findings of previous studies that used conventional VEs. The detrimental effects on participants' spatial knowledge of using hyperlinks for movement were reduced when a time-delay was introduced, but participants still developed less accurate knowledge than they did in the conventional VEs. Visual continuity had a greater influence on participants' rate of learning than continuity of movement, and participants were able to exploit hyperlinks that connected together disparate regions of a VE to reduce travel time

Visual Analytics of Event Data using Multiple Mining Methods

Most researchers use a single method of mining to analyze event data. This paper uses case studies from two very differentdomains (electronic health records and cybersecurity) to investigate how researchers can gain breakthrough insights by com-bining multiple event mining methods in a visual analytics workflow. The aim of the health case study was to identify patternsof missing values, which was daunting because the 615 million missing values occurred in 43,219 combinations of fields. How-ever, a workflow that involved exclusive set intersections (ESI), frequent itemset mining (FIM) and then two more ESI stepsallowed us to identify that 82% of the missing values were from just 244 combinations. The cybersecurity case study’s aim wasto understand users’ behavior from logs that contained 300 types of action, gathered from 15,000 sessions and 1,400 users.Sequential frequent pattern mining (SFPM) and ESI highlighted some patterns in common, and others that were not. For thelatter, SFPM stood out for its ability to action sequences that were buried within otherwise different sessions, and ESI detectedsubtle signals that were missed by SFPM. In summary, this paper demonstrates the importance of using multiple perspectives,complementary set mining methods and a diverse workflow when using visual analytics to analyze complex event data

Field testing methodology for investigating the effect of systemic insecticides on honey bees

contribution to session IVTest methodolog

Symmetric and asymmetric action integration during cooperative object manipulation in virtual environments

Cooperation between multiple users in a virtual environment (VE) can take place at one of three levels. These are defined as where users can perceive each other (Level 1), individually change the scene (Level 2), or simultaneously act on and manipulate the same object (Level 3). Despite representing the highest level of cooperation, multi-user object manipulation has rarely been studied. This paper describes a behavioral experiment in which the piano movers' problem (maneuvering a large object through a restricted space) was used to investigate object manipulation by pairs of participants in a VE. Participants' interactions with the object were integrated together either symmetrically or asymmetrically. The former only allowed the common component of participants' actions to take place, but the latter used the mean. Symmetric action integration was superior for sections of the task when both participants had to perform similar actions, but if participants had to move in different ways (e.g., one maneuvering themselves through a narrow opening while the other traveled down a wide corridor) then asymmetric integration was superior. With both forms of integration, the extent to which participants coordinated their actions was poor and this led to a substantial cooperation overhead (the reduction in performance caused by having to cooperate with another person)

Using Miniature Visualizations of Descriptive Statistics to Investigate the Quality of Electronic Health Records

Descriptive statistics are typically presented as text, but that quickly becomes overwhelming when datasets contain many variables or analysts need to compare multiple datasets. Visualization offers a solution, but is rarely used apart from to show cardinalities (e.g., the % missing values) or distributions of a small set of variables. This paper describes dataset- and variable-centric designs for visualizing three categories of descriptive statistic (cardinalities, distributions and patterns), which scale to more than 100 variables, and use multiple channels to encode important semantic differences (e.g., zero vs. 1+ missing values). We evaluated our approach using large (multi-million record) primary and secondary care datasets. The miniature visualizations provided our users with a variety of important insights, including differences in character patterns that indicate data validation issues, missing values for a variable that should always be complete, and inconsistent encryption of patient identifiers. Finally, we highlight the need for research into methods of identifying anomalies in the distributions of dates in health data

A set-based visual analytics approach to analyze retail data

This paper explores how a set-based visual analytics approach could be useful for analyzing customers' shopping behavior, and makes three main contributions. First, it describes the scale and characteristics of a real-world retail dataset from a major supermarket. Second, it presents a scalable visual analytics workflow to quickly identify patterns in shopping behavior. To assess the workflow, we conducted a case study that used data from four convenience stores and provides several insights about customers' shopping behavior. Third, from our experience with analyzing real-world retail data and comments made by our industry partner, we outline four research challenges for visual analytics to tackle large set intersection problems

Phylogenetic Analysis of Kindlins Suggests Subfunctionalization of an Ancestral Unduplicated Kindlin into Three Paralogs in Vertebrates

Kindlin proteins represent a newly discovered family of evolutionarily conserved FERM domain-containing proteins. This family includes three highly conserved proteins: Kindlin-1, Kindlin-2 and Kindlin-3. All three Kindlin proteins are associated with focal adhesions and are involved in integrin activation. The FERM domain of each Kindlin is bipartite and plays a key role in integrin activation. We herein explore for the first time the evolutionary history of these proteins. The phylogeny of the Kindlins suggests a single ancestral Kindlin protein present in even the earliest metazoan ie, hydra. This protein then underwent duplication events in insects and also experienced genome duplication in vertebrates, leading to the Kindlin family. A comparative study of the Kindlin paralogs showed that Kindlin-2 is the slowest evolving protein among the three family members. The analysis of synonymous and non-synonymous substitutions in orthologous Kindlin sequences in different species showed that all three Kindlins have been evolving under the influence of purifying selection. The expression pattern of Kindlins along with phylogenetic studies supports the subfunctionalization model of gene duplication