Information-seeking behaviours and cognitive search strategies in different search tasks on the WWW

This study investigates the cognitive strategies of 80 participants as they engaged in two researcher-defined tasks and two participant-defined information-seeking tasks using the WWW. Each researcher-defined task and participant-defined task was further divided into a directed search task and a general-purpose browsing task. On the basis of retrospective verbal protocols, log-file data and observations, 12 cognitive search strategies were identified and explained. The differences in cognitive search strategy choice between researcher-defined and participant-defined tasks and between directed search and general-purpose tasks were examined using correspondence analysis. These cognitive search strategies were compared to earlier investigations of search strategies on the WWW.

Relevance to industry

Describing information-seeking behaviours and cognitive search strategies in detail provides website developers and search engine developers with valuable insights into how users seek (and find) information of value to them. Using this information, website developers might gain some knowledge as to how to best represent the content and navigational properties of websites. Search engine developers might wish to make the search and collection strategies more transparent to users. There are also design implications for the designers of web browsers.     

The cognitive benefits of dynamic representations in the acquisition of spatial navigation skills

A representational theory of the mind suggests that human experiences and activities are underpinned by mental representations. This abstract task representation paradigm may explain a cognitive benefit of dynamic instructional visualisations over static alternative in the acquisition of novel procedural motor skills. In this sequel work, we explore and extend this view through empirical investigations of novel skill acquisitions in a separate but related domain of spatial navigation. We compare the post-learning virtual maze navigational performance of sixty novel learners across two groups. After controlling for spatial orientation ability and prior video gaming experience, participants that learned the task using dynamic instructional visualisations recorded significantly better performance measures than those in the static group. Additionally, within-group comparisons also show that the beneficial advantage of dynamic instructional visualisations over statics remained consistent across different task complexities. These findings provide further evidence to support the view that dynamic instructional visualisations afford more efficient transfer of novel procedural skills through computer based training than static visualisations. This has implications for instructional design especially when rapid novel situational awareness is desired such as in briefings for emergency firefighting or tactical military operations.     

Spatial navigation in large-scale virtual environments: Gender differences in survey tasks

Most of the studies on gender differences in spatial abilities have focused on traditional paper and pencil cognitive tests, while these differences have been less investigated in navigational tasks carried out in complex virtual environments (VEs). The aim of the present study has been to evaluate gender differences in route and survey knowledge by means of specific tasks (route-learning, pointing, landmark-placing) carried out in two separate VEs. In addition the male and female participants were subjected to a battery of spatial abilities tests and specific self-report questionnaires. The results showed a significant difference favouring males in the survey tasks, as well as in the spatial abilities tests; on the contrary, no gender differences were found in the route task. Moreover, a different pattern of correlations among the measures were found in the male and female sub-groups.     

Time-sharing revisited: Test of a componential model for the assessment of individual differences

Abstract

Time-sharing ability as an individual differences variable in dual task performance was examined using a componential model. Five proposed components were assessed: (1) serial processing ability; (2) an internal model of the system dynamics; (3) performing heterogeneous operations; (4) adaptation to rapidly changing dynamic conditions; (5) parallel processing ability. The approach combined methodologies from experimental psychology and from individual differences research. Forty subjects were given four single task pretests, and then performed a compensatory tracking task in various dual task combinations administered during six sessions over a period of three days. At the conclusion of the experiment the subjects had to perform three different dual task transfer tasks. The results of a factor analysis and a series of stepwise multiple-regression analyses revealed two important dimensions of individual differences in dual task performance: (1) individual differences in cognitive style linked to the concept of field dependence/independence; (2) individual differences in time-sharing ability. The individual differences in cognitive style were identified by the first derived factor. It was defined by the measures that represent serial and parallel processing. Based on the opposing signs, positive for the serial processing measures and negative for the parallel processing measures, it was concluded that this factor is bipolar, representing two distinct strategies. Further-analyses suggested that the strategy differences may be linked to individual differences in field dependence/independence. Individual differences in time-sharing ability were identified by the second derived factor of the factor analysis and through multiple-regression analysis. Based on the results the concept of a ‘process-specific’ time-sharing ability was introduced.     

Information visualization; assisting low spatial individuals with information access tasks through the use of visual mediators

This study investigated the use of visual mediators to facilitate information access by low spatial individuals. Based on theories of adaptive learning and field-dependence, two human-computer interfaces were developed which were intended to compensate for the inability of low spatial individuals to readily construct visual mental models of a menu system's structure. The two compensatory interfaces included: a 2D visual hierarchy and a linear structure. The information search performance of high and low spatial individuals was compared on the two compensatory interfaces and a third challenge match interface, which challenged individuals to construct a mental model of a hierarchical menu system in order to perform efficiently. The visual mediators were successful in accommodating low spatial individuals, as indicated by the lack of any significant performance differences being detected between the high and low spatial groups on the two compensatory interfaces. High spatial individuals outperformed low spatial individuals only when information search tasks required the use of spatial ability in mentally constructing a model of the organization and structure of embedded task information. The key factor in the accommodation process was the elimination of the need to mentally visualize the structure of embedded task information. These results indicate that visualization techniques can be successfully used to enhance the information search performance of low spatial individuals.     

Effects of alcohol and caffeine on maritime navigational skills

Twelve experienced navigators participated in an experiment to determine the effects of alcohol, caffeine, and an alcohol+caffeine mixture on performance during the following tasks: visual search, the search and location of items on a navigational chart (chartsearch) and the solving of maritime navigational problems. Alcohol (75 ml) produced impairment in performance on visual search (p<0.05) and navigational problem-solving (p<0.01). Caffeine was found to enhance performance on visual search (p<0.05) but not on the chartsearch, although a significant correlation was found between performance on the two tests (p<0.05). Caffeine was not found to improve the accuracy of navigational problem-solving (p>0.05). Neither alcohol nor caffeine had any significant effect on the speed of problem-solving (p>0.05).     

Video game experience predicts virtual, but not real navigation performance

In recent years, studies have shown that video game experience is related to improvements across a variety of cognitive and visuospatial tasks. This study investigated the relationship between prior video game experience and spatial performance in virtual and real environments. Across two experiments, gaming experience was related to performance in desktop virtual environments; those with more video game experience were more accurate in pointing to nonvisible targets. In contrast, gaming experience was unrelated to three different real environment tasks, suggesting that video games may primarily influence perceptual and cognitive abilities in the visual domain over abilities that also involve kinesthetic or vestibular input. Contrary to expectations, gaming experience was also related to performance in immersive virtual environments, which may be related to the use of a joystick interface during immersive travel. Video game experience was also positively related to performance in a dynamic spatial task and to verbal SAT and math SAT scores. Sex differences in desktop virtual navigation and dynamic spatial ability were eliminated when game experience was included as a covariate.     

The role of spatial abilities and age in performance in an auditory computer navigation task

Age-related differences in spatial ability have been suggested as a mediator of age-related differences in computer-based task performance. However, the vast majority of tasks studied have primarily used a visual display (e.g., graphical user interfaces). In the current study, the relationship between spatial ability and performance in a non-visual computer-based navigation task was examined in a sample of 196 participants ranging in age from 18 to 91. Participants called into a simulated interactive voice response system and carried out a variety of transactions. They also completed measures of attention, working memory, and spatial abilities. The results showed that age-related differences in spatial ability predicted a significant amount of variance in performance in the non-visual computer task, even after controlling for other abilities. Understanding the abilities that influence performance with technology may provide insight into the source of age-related performance differences in the successful use of technology.     

The role of spatial abilities and age in performance in an auditory computer navigation task

Age-related differences in spatial ability have been suggested as a mediator of age-related differences in computer-based task performance. However, the vast majority of tasks studied have primarily used a visual display (e.g., graphical user interfaces). In the current study, the relationship between spatial ability and performance in a non-visual computer-based navigation task was examined in a sample of 196 participants ranging in age from 18 to 91. Participants called into a simulated interactive voice response system and carried out a variety of transactions. They also completed measures of attention, working memory, and spatial abilities. The results showed that age-related differences in spatial ability predicted a significant amount of variance in performance in the non-visual computer task, even after controlling for other abilities. Understanding the abilities that influence performance with technology may provide insight into the source of age-related performance differences in the successful use of technology.     

Implications of User Characteristics in Information Seeking on the World Wide Web

The study described in this article investigated how differences in cognitive style and online search experience influence the search performance and navigational pattern of individuals utilizing a university World Wide Web (WWW) site. Forty-eight undergraduate students with diverse academic backgrounds participated in the study. On the basis of cognitive style and prior experience with online database search, the participants were assigned to 1 of the following groups: (a) field-dependent (FD) with little or no online search experience, (b) FD with substantial online search experience, (c) field-independent (FI) with little or no online search experience, and (d) FI with substantial online search experience. It was found that cognitive style influenced search time, whereas online search experience affected navigational style, such as jumps and layer traversal. Cognitive style and online search experience also interacted to influence search performance and navigational style. FDs with little or no online search experience navigated the WWW in a fairly linear mode, using embedded links frequently. They also tended to visit more nodes and used "Home" more frequently than the rest. The results imply that as FD searchers gain more online search experience, their navigational style and search performance change and become comparable to that of FDs. Based on these findings, some suggestions are made to improve the WWW interface and WWW user training programs.     

Attentional costs and failures in air traffic control notifications

Large display screens are common in supervisory tasks, meaning that alerts are often perceived in peripheral vision. Five air traffic control notification designs were evaluated in their ability to capture attention during an ongoing supervisory task, as well as their impact on the primary task. A range of performance measures, eye-tracking and subjective reports showed that colour, even animated, was less effective than movement, and notifications sometimes went unnoticed. Designs that drew attention to the notified aircraft by a pulsating box, concentric circles or the opacity of the background resulted in faster perception and no missed notifications. However, the latter two designs were intrusive and impaired primary task performance, while the simpler animated box captured attention without an overhead cognitive cost. These results highlight the need for a holistic approach to evaluation, achieving a balance between the benefits for one aspect of performance against the potential costs for another.

Practitioner summary: We performed a holistic examination of air traffic control notification designs regarding their ability to capture attention during an ongoing supervisory task. The combination of performance, eye-tracking and subjective measurements demonstrated that the best design achieved a balance between attentional power and the overhead cognitive cost to primary task performance.     

Visual search in vibration environments: Effects of spatial ability,stimulus size and stimulus density

Visual search is one type of common encountered human-computer interaction tasks, but it has less been examined in vibration environments. The aim of this study was to examine the effects of one user characteristic (spatial ability) and two stimulus characteristics (i.e., stimulus size and stimulus density) on visual search performance during single- and double-target tasks in simulated vibration environments. Twenty-four participants attended an experiment where they were instructed to perform single- and double-target visual search tasks with varied levels of stimulus size and stimulus density under static, slight and moderate vibration environments, respectively. Results indicated that the two vibration conditions achieved comparable visual search performance, perceived visual fatigue, and perceived comfort with static condition across task types. Stimuli size and stimulus density yielded significant effects on visual search time in both single- and double-target tasks (p's < 0.001). Participants with high spatial ability were faster than those with low spatial ability in double-target tasks (p = 0.042). Users preferred interface design with medium-to-large stimulus size and low-to-medium stimulus density in visual search.     

Sensitivity of the lane change test as a measure of in-vehicle system demand

The Lane Change Test (LCT) is one of the growing number of methods developed to quantify driving performance degradation brought about by the use of in-vehicle devices. Beyond its validity and reliability, for such a test to be of practical use, it must also be sensitive to the varied demands of individual tasks. The current study evaluated the ability of several recent LCT lateral control and event detection parameters to discriminate between visual-manual and cognitive surrogate In-Vehicle Information System tasks with different levels of demand. Twenty-seven participants (mean age 24.4 years) completed a PC version of the LCT while performing visual search and math problem solving tasks. A number of the lateral control metrics were found to be sensitive to task differences, but the event detection metrics were less able to discriminate between tasks. The mean deviation and lane excursion measures were able to distinguish between the visual and cognitive tasks, but were less sensitive to the different levels of task demand. The other LCT metrics examined were less sensitive to task differences. A major factor influencing the sensitivity of at least some of the LCT metrics could be the type of lane change instructions given to participants. The provision of clear and explicit lane change instructions and further refinement of its metrics will be essential for increasing the utility of the LCT as an evaluation tool.     

Situational awareness ability and cognitive skills training in a complex real-world task

Successful performance in complex dynamic environments depends on domain-dependent factors, such as situational awareness (SA). Underlying SA in a domain are domain-independent cognitive abilities in perception, memory, attention and executive control. Individuals with lower underlying ability perform relatively poorly in complex dynamic real-world tasks. The first experiment examined whether cognitive skills training could overcome limitations in underlying SA ability that impact on complex dynamic task performance. Participants were taught a mix of cognitive management strategies (e.g. divided and focused attention and visual search) in a simulated air traffic control task. A second experiment investigated the link between underlying SA ability, TRACON and SAGAT, a widely used measure of domain-specific SA. In a third experiment, the focus was on encouraging participants to plan ahead and consider the interrelations of elements (aircraft) in the environment. Whilst both training methods ameliorated the negative impact that lower SA ability had on complex dynamic task performance, the results of the third study indicated that this may have been achieved through improved planning behaviour. Finally, participants with higher underlying SA ability performed well irrespective of training condition.     

Situational awareness ability and cognitive skills training in a complex real-world task

Successful performance in complex dynamic environments depends on domain-dependent factors, such as situational awareness (SA). Underlying SA in a domain are domain-independent cognitive abilities in perception, memory, attention and executive control. Individuals with lower underlying ability perform relatively poorly in complex dynamic real-world tasks. The first experiment examined whether cognitive skills training could overcome limitations in underlying SA ability that impact on complex dynamic task performance. Participants were taught a mix of cognitive management strategies (e.g. divided and focused attention and visual search) in a simulated air traffic control task. A second experiment investigated the link between underlying SA ability, TRACON and SAGAT, a widely used measure of domain-specific SA. In a third experiment, the focus was on encouraging participants to plan ahead and consider the interrelations of elements (aircraft) in the environment. Whilst both training methods ameliorated the negative impact that lower SA ability had on complex dynamic task performance, the results of the third study indicated that this may have been achieved through improved planning behaviour. Finally, participants with higher underlying SA ability performed well irrespective of training condition.     

Age differences and the acquisition of spatial knowledge in a three-dimensional environment: Evaluating the use of an overview map as a navigation aid

This study examined age differences in the use of an electronic three-dimensional (3D) environment, and how the age differences were affected by the use of an overview map as a navigation aid. Task performance and the subjects’ acquisition of configural knowledge of the 3D-environment were assessed. Impact of spatial ability and prior experience on these measurements were also investigated. One group of older subjects (n=24) and one group of younger subjects (n=24) participated. An overall hypothesis for the work presented here was that differences in learning to and performing navigational tasks in the physical world are similar in learning and performing navigational tasks in the virtual world. The results showed that the older participants needed more time to solve the tasks; and similar to navigation in the physical world, the older participants were less likely to create configural knowledge. It could not be established that older participants benefited more from an overview map as cognitive support than younger subjects, except in the subjective sense: the older users felt more secure when the map was there. The map seemed to have supported the older users in creating a feeling of where objects were located within the environment, but it did not make them more efficient. The results have implications for design; in particular, it brings up the difficult issue of balancing design goals such as efficiency in terms of time and functionality, against maintaining a sense of direction and location in navigational situations.     

The effects of whole-body restriction on task performance

Many occupations, particularly involving maintenance operations, require individuals to perform both physical tasks and mental tasks in restricted spaces. Researchers have examined physical task performance under various restrictions; however, little research has investigated the effects of restricted space on cognitive tasks. Cognitive task performance in restricted spaces presents cognitive demands (i.e. the task itself) as well as additional physical demands (e.g. awkward postures), which may adversely affect task performance or operator workload. This research focused on the effects of whole-body restrictions on cognitive task performance. An experiment was conducted that examined 9 levels of restriction created in a laboratory: an unrestricted control, 6 single whole-body restrictions at two severity levels (2 lateral, 2 sagittal and 2 vertical) and 2 multiple restrictions (sagittal/vertical, lateral/sagittal/vertical). An inspection task served as the cognitive task. Behavioural, physiological and psychophysical measures were collected and analysed to measure the operator and performance effects. Operator response differences were found among the various forms of restriction as well as the severity level of similar forms of restriction. Increasing restriction significantly affected the behavioural and physiological operator response as opposed to the cognitive response.     

The effects of whole-body restriction on task performance

Many occupations, particularly involving maintenance operations, require individuals to perform both physical tasks and mental tasks in restricted spaces. Researchers have examined physical task performance under various restrictions; however, little research has investigated the effects of restricted space on cognitive tasks. Cognitive task performance in restricted spaces presents cognitive demands (i.e. the task itself) as well as additional physical demands (e.g. awkward postures), which may adversely affect task performance or operator workload. This research focused on the effects of whole-body restrictions on cognitive task performance. An experiment was conducted that examined 9 levels of restriction created in a laboratory: an unrestricted control, 6 single whole-body restrictions at two severity levels (2 lateral, 2 sagittal and 2 vertical) and 2 multiple restrictions (sagittal/vertical, lateral/sagittal/vertical). An inspection task served as the cognitive task. Behavioural, physiological and psychophysical measures were collected and analysed to measure the operator and performance effects. Operator response differences were found among the various forms of restriction as well as the severity level of similar forms of restriction. Increasing restriction significantly affected the behavioural and physiological operator response as opposed to the cognitive response.     

Effects of alcohol and caffeine on maritime navigational skills

Twelve experienced navigators participated in an experiment to determine the effects of alcohol, caffeine, and an alcohol + caffeine mixture on performance during the following tasks: visual search, the search and location of items on a navigational chart (chartsearch) and the solving of maritime navigational problems. Alcohol (75 ml) produced impairment in performance on visual search (p&lt; 0.05) and navigational problem-solving (p< 0.01). Caffeine was found to enhance performance on visual search (p< 0.05) but not on the chartsearch, although a significant correlation was found between performance on the two tests (p< 0.05). Caffeine was not found to improve the accuracy of navigational problem-solving (p> 0.05). Neither alcohol nor caffeine had any significant effect on the speed of problem-solving (p> 0.05).     

Does situation awareness add to the validity of cognitive tests?

OBJECTIVE: Does adding situation awareness (SA) to a battery of cognitive tests improve prediction? BACKGROUND: Identifying variables that predict skilled performance in a complex task aids in understanding the nature of skill and also aids in the selection of operators to perform that task. SA is thought to be an important predictor of performance. SA is often thought to be based on underlying cognitive mechanisms. METHOD: Three performance measures taken from the Federal Aviation Administration's (FAA's) Air Traffic Scenarios Test, the low-fidelity simulation component of the FAA's controller selection battery, were used as criterion variables in a hierarchical regression. After predicting performance based on a battery of cognitive (e.g., intelligence, working memory, spatial memory) and noncognitive tests (e.g., cognitive style, personality, demographics), we added measures of SA. RESULTS: SA did provide increases in prediction, but only when measured with the Situation Present Assessment Method, an on-line query method. When the same questions were asked off line, SA did not enter the model in two cases and improved prediction by only 2% in the third. CONCLUSION: Thus, some measures of SA do show incremental validity, even against a backdrop of a large number of cognitive variables. APPLICATION: On-line measures of SA can be a worthwhile addition to standard batteries of tests used to predict performance in cognitively oriented industrial tasks.