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Anaby, D., Vrotsou, K., Kroksmark, U. & Ellegård, K. (2019). Changes in participation patterns of youth with physical disabilities following the Pathways and Resources for Engagement and Participation intervention: A time-geography approach. Scandinavian Journal of Occupational Therapy
Open this publication in new window or tab >>Changes in participation patterns of youth with physical disabilities following the Pathways and Resources for Engagement and Participation intervention: A time-geography approach
2019 (English)In: Scandinavian Journal of Occupational Therapy, ISSN 1103-8128, E-ISSN 1651-2014Article in journal (Refereed) Epub ahead of print
Abstract [en]

Background: The PREP (Pathways and Resources for Engagement and Participation), an innovative 12-week occupational therapy intervention that focuses on changing the environment, was found effective in improving the participation of youth in specific chosen community-based activities.

Objective: To complement existing evidence, this study explored changes in overall participation patterns of youth with physical disabilities following the PREP intervention.

Methods: Guided by time-geography approach, 13 youth aged 12–17 completed a 24-hr diary using the Aday app during one typical weekday and another day during the weekend, pre- and post-intervention. Data of 50 diaries were plotted and analyzed using the VISUALTimePAcTS program.

Results: Following the PREP, youth were engaged in less digital media and more in study-related activities. Number of occurrences and time spent doing activities with friends were greater post-intervention, whereas time spent doing activities at home was quite similar, particularly during the weekdays. During the weekends, however, youth spent slightly less time at home.

Conclusions and significance: Findings provide preliminary support for the effectiveness of the PREP, extending beyond the accomplishment of specific targeted activities towards a change in the overall daily patterns of youth. Such knowledge can redirect occupational therapists’ attention to environment-focused interventions involving real-life experiences.

Place, publisher, year, edition, pages
Informa Healthcare, 2019
Keywords
Diary data, adolescents, time-use, rehabilitation
National Category
Occupational Therapy
Identifiers
urn:nbn:se:liu:diva-153941 (URN)10.1080/11038128.2018.1554088 (DOI)30661444 (PubMedID)
Available from: 2019-01-21 Created: 2019-01-21 Last updated: 2019-01-23Bibliographically approved
Vrotsou, K. & Nordman, A. (2019). Exploratory visual sequence mining based on pattern-growth. IEEE Transactions on Visualization and Computer Graphics, 25(8), 2597-2610
Open this publication in new window or tab >>Exploratory visual sequence mining based on pattern-growth
2019 (English)In: IEEE Transactions on Visualization and Computer Graphics, ISSN 1077-2626, E-ISSN 1941-0506, Vol. 25, no 8, p. 2597-2610Article in journal (Refereed) Published
Abstract [en]

Sequential pattern mining finds applications in numerous diverging fields. Due to the problem's combinatorial nature, two main challenges arise. First, existing algorithms output large numbers of patterns many of which are uninteresting from a user's perspective. Second, as datasets grow, mining large number of patterns gets computationally expensive. There is, thus, a need for mining approaches that make it possible to focus the pattern search towards directions of interest. This work tackles this problem by combining interactive visualization with sequential pattern mining in order to create a "transparent box" execution model. We propose a novel approach to interactive visual sequence mining that allows the user to guide the execution of a pattern-growth algorithm at suitable points through a powerful visual interface. Our approach (1) introduces the possibility of using local constraints during the mining process, (2) allows stepwise visualization of patterns being mined, and (3) enables the user to steer the mining algorithm towards directions of interest. The use of local constraints significantly improves users' capability to progressively refine the search space without the need to restart computations. We exemplify our approach using two event sequence datasets; one composed of web page visits and another composed of individuals' activity sequences.

Keywords
Sequential pattern mining, interactive mining, visual data mining, mining with constraints
National Category
Computer and Information Sciences Media and Communication Technology
Identifiers
urn:nbn:se:liu:diva-153938 (URN)10.1109/TVCG.2018.2848247 (DOI)000473597800007 ()29994660 (PubMedID)
Note

Funding agencies: CENIIT, Center for Industrial Information Technology at Linkoping University; RESKILL project - public research and innovation funds from the Swedish Transport Administration; Swedish Maritime Administration; Swedish Air Navigation Service Provider LFV

Available from: 2019-01-20 Created: 2019-01-20 Last updated: 2019-07-19
Muthumanickam, P., Vrotsou, K., Vitoria, A., Johansson, J. & Cooper, M. (2018). Identification of Temporally Varying Areas of Interest in Long-Duration Eye-Tracking Data Sets. IEEE Transactions on Visualization and Computer Graphics
Open this publication in new window or tab >>Identification of Temporally Varying Areas of Interest in Long-Duration Eye-Tracking Data Sets
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2018 (English)In: IEEE Transactions on Visualization and Computer Graphics, ISSN 1077-2626, E-ISSN 1941-0506Article in journal (Refereed) Published
Abstract [en]

Eye-tracking has become an invaluable tool for the analysis of working practices in many technological fields of activity. Typically studies focus on short tasks and use static expected areas of interest (AoI) in the display to explore subjects’ behaviour, making the analyst’s task quite straightforward. In long-duration studies, where the observations may last several hours over a complete work session, the AoIs may change over time in response to altering workload, emergencies or other variables making the analysis more difficult. This work puts forward a novel method to automatically identify spatial AoIs changing over time through a combination of clustering and cluster merging in the temporal domain. A visual analysis system based on the proposed methods is also presented. Finally, we illustrate our approach within the domain of air traffic control, a complex task sensitive to prevailing conditions over long durations, though it is applicable to other domains such as monitoring of complex systems. 

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2018
Keywords
Eye-tracking data, areas of interest, clustering, minimum spanning tree, temporal data, spatio-temporal data
National Category
Computer Systems
Identifiers
urn:nbn:se:liu:diva-152714 (URN)10.1109/TVCG.2018.2865042 (DOI)000452640000009 ()30183636 (PubMedID)2-s2.0-85052788669 (Scopus ID)
Note

Funding agencies: Swedish Research Council [2013-4939]; RESKILL project - Swedish Transport Administration; Swedish Maritime Administration; Swedish Air Navigation Service Provider LFV

Available from: 2018-11-16 Created: 2018-11-16 Last updated: 2019-01-07Bibliographically approved
Haga, M., Vrotsou, K. & Bredland, E. (2018). Visualizing Physical Activity Patterns among Community-Dwelling Older Adults: A Pilot Study. Sports, 6(4), Article ID 135.
Open this publication in new window or tab >>Visualizing Physical Activity Patterns among Community-Dwelling Older Adults: A Pilot Study
2018 (English)In: Sports, ISSN 2075-4663, Vol. 6, no 4, article id 135Article in journal (Refereed) Published
Abstract [en]

Regular physical activity relates to physical and mental functioning in older people, and promoting physical activity has the potential to substantially reduce functional decline and improve well-being. Despite this, investigations of the physical activity quotient through participation in functional activities in everyday life have traditionally gained limited focus among older populations compared to leisure-time physical activity and exercise. Considering the accumulated evidence of the health benefits of low-intensity physical activity, exploring and measuring such activities in this population is highly relevant. The aim of this study was to visualize and describe older people’s physical activity patterns in daily life using a time-geographic approach in combination with the estimation of metabolic equivalents (METS). To exemplify the new method, a sample of nine retired men (65–82 years old, mean age 76.4 ± 5.8) with no homecare services from the municipality was recruited. In order to enable a visual analysis of the physical activity patterns in daily life, we developed the VISUAL-PA software, which is a visual analysis tool that includes METS to account for intensity and enables the analysis of distinct types and domains of physical activity. The VISUAL-PA software creates graphic outputs of physical activity patterns that enable the identification, visualization, and analysis of distinct types and intensities of physical activity in addition to sedentary behavior. The use of VISUAL-PA can contribute to a broader understanding of the complexity in physical activity patterns among older adults in terms of dimensions such as activity patterns and habits, domains, and intensity level. To strengthen the public health strategies that promote health and an active lifestyle, additional knowledge about physical activity patterns is necessary. Moreover, the visualization of physical activity can enable reflections on and awareness of activity habits and preferences, and thus facilitate behavior changes in older individuals.

Place, publisher, year, edition, pages
MDPI, 2018
Keywords
time-geographic perspective; visualization; physical activity patterns; energy expenditure
National Category
Physiotherapy
Identifiers
urn:nbn:se:liu:diva-153937 (URN)10.3390/sports6040135 (DOI)30380724 (PubMedID)
Available from: 2019-01-20 Created: 2019-01-20 Last updated: 2019-03-29Bibliographically approved
Vrotsou, K., Fuchs, G., Andrienko, N. & Andrienko, G. (2017). An Interactive Approach for Exploration of Flows Through Direction-Based Filtering. Journal of Geovisualization and Spatial Analysis, 1(1-2), Article ID 1.
Open this publication in new window or tab >>An Interactive Approach for Exploration of Flows Through Direction-Based Filtering
2017 (English)In: Journal of Geovisualization and Spatial Analysis, ISSN 2509-8810, Vol. 1, no 1-2, article id 1Article in journal (Refereed) Published
Abstract [en]

This paper is concerned with the representation and exploration of flows, defined as spatial interactions between geographic locations. Flows are challenging to display in a comprehensible manner due to the nature of the data, which are characterized by many crossings and overlaps leading to clutter. A number of different strategies have been suggested for addressing this problem, which commonly involve reducing the search space, aggregating the data or simplifying the representations often at the cost of information loss or distortion of spatial context. We propose an interactive approach for exploring large and highly connected networks of flows without distorting the geographical space and without losing the context overview in the process. The approach is based on a flow-specific interaction technique for filtering the data by direction, that enables an analyst to successively identify underlying spatial arrangement patterns. We illustrate our approach through exploring flows of tourists and locals in the Greater London area.

Place, publisher, year, edition, pages
Springer, 2017
Keywords
Flow analysis, Spatial arrangement pattern, Interactive query, Direction-based filtering
National Category
Computer and Information Sciences
Identifiers
urn:nbn:se:liu:diva-140189 (URN)10.1007/s41651-017-0001-7 (DOI)
Available from: 2017-09-03 Created: 2017-09-03 Last updated: 2019-07-11Bibliographically approved
Ceccato, V., Wiebe, D. J., Eshraghi, B. & Vrotsou, K. (2017). Women’s Mobility and the Situational Conditions of Rape: Cases Reported to Hospitals. Journal of Interpersonal Violence
Open this publication in new window or tab >>Women’s Mobility and the Situational Conditions of Rape: Cases Reported to Hospitals
2017 (English)In: Journal of Interpersonal Violence, ISSN 0886-2605, E-ISSN 1552-6518Article in journal (Refereed) Published
Abstract [en]

A third of all rapes in Stockholm, the capital of Sweden, take place in public outdoor places. Yet, little is known about the events that precede this type of sexual offence and less about the situational context of rape. This study aims to improve the understanding of the nature of situational conditions that immediately precede events of rape. Using medical records of 147 rape victims during 2012 and 2013, we constructed time- and place-specific records of the places women traveled through or spent time at, the activities they engaged in, and the people they interacted with sequentially over the course of the day when they were raped. The analysis uses visualization tools (VISUAL-TimePAcTS), Geographical Information Systems, and conditional logistic regression to identify place-, context-, and social interaction–related factors associated with the onset of rape. Results for this sample of cases reported to hospitals show that being outdoors was not necessarily riskier for women when compared with indoor public settings; some outdoor environments were actually protective, such as streets. Being in a risky social context and engaging in a risky activity before the event was associated with an increased risk of rape, and the risk escalated over the day. Among those women who never drank alcohol, the results were similar to what was observed in the overall sample, which suggests that risky social interaction and risky activity made independent contributions to the risk of rape. The article finishes with suggestions for rape prevention.

Place, publisher, year, edition, pages
Sage Publications, 2017
Keywords
sexual violence, visualization techniques, GIS, case-crossover design
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Identifiers
urn:nbn:se:liu:diva-140190 (URN)10.1177/0886260517699950 (DOI)
Available from: 2017-09-03 Created: 2017-09-03 Last updated: 2017-09-07Bibliographically approved
Mattioli, G., Anable, J. & Vrotsou, K. (2016). Car dependent practices: Findings from a sequence pattern mining study of UK time use data. Transportation Research Part A: Policy and Practice, 89, 56-72
Open this publication in new window or tab >>Car dependent practices: Findings from a sequence pattern mining study of UK time use data
2016 (English)In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 89, p. 56-72Article in journal (Refereed) Published
Abstract [en]

This paper identifies three main understandings of the notion of car dependence in transport research: a micro-social understanding (dependence as an attribute of individuals), a macro approach (attribute of societies or local areas as whole), and a meso-level understanding, where it refers to trips - or rather to the activities that people travel to undertake. While the first two approaches have been dominant, this paper further develops the third, addressing questions as to whether and why certain activities are inherently more difficult to switch away from the car. At the theoretical level, it builds on theories of social practice to put forward the notion of car dependent practices. At the empirical level, it demonstrates that the application of sequence pattern mining techniques to time use data allows the identification of car and mobility intensive activities, arguably representing the trace of car dependent practices. Overall, the findings of this mining exercise suggest that the emphasis of existing literature on escorting children, shopping and carrying heavy goods as car dependent trip purposes is not misplaced. Our analysis adds to this knowledge by contextualising the information by providing detailed quantitative analysis of a larger, richer set of activities hitherto overlooked in transport policy. The article concludes by illustrating the policy implications of the approach adopted and the findings generated, discussing possible strategies to steer practices in a more sustainable direction by creating material alternatives to the cargo function of car travel. (C) 2016 The Author(s). Published by Elsevier Ltd.

Place, publisher, year, edition, pages
PERGAMON-ELSEVIER SCIENCE LTD, 2016
Keywords
Car dependence; Social practices; Time use; Sequence analysis; Pattern mining; Shopping
National Category
Social Sciences Interdisciplinary
Identifiers
urn:nbn:se:liu:diva-130413 (URN)10.1016/j.tra.2016.04.010 (DOI)000379557300005 ()
Note

Funding Agencies|Engineering and Physical Sciences Research Council, RCUK Energy Programme [EP/K011723/1]; EDF, R&D ECLEER Programme

Available from: 2016-08-15 Created: 2016-08-05 Last updated: 2018-01-10
Vrotsou, K., Janetzko, H., Navarra, C., Fuchs, G., Spretke, D., Mansmann, F., . . . Andrienko, G. (2015). SimpliFly: A Methodology for Simplification and Thematic Enhancement of Trajectories. IEEE Transactions on Visualization and Computer Graphics, 21(1), 107-121
Open this publication in new window or tab >>SimpliFly: A Methodology for Simplification and Thematic Enhancement of Trajectories
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2015 (English)In: IEEE Transactions on Visualization and Computer Graphics, ISSN 1077-2626, E-ISSN 1941-0506, Vol. 21, no 1, p. 107-121Article in journal (Refereed) Published
Abstract [en]

Movement data sets collected using todays advanced tracking devices consist of complex trajectories in terms of length, shape, and number of recorded positions. Multiple additional attributes characterizing the movement and its environment are often also included making the level of complexity even higher. Simplification of trajectories can improve the visibility of relevant information by reducing less relevant details while maintaining important movement patterns. We propose a systematic stepwise methodology for simplifying and thematically enhancing trajectories in order to support their visual analysis. The methodology is applied iteratively and is composed of: (a) a simplification step applied to reduce the morphological complexity of the trajectories, (b) a thematic enhancement step which aims at accentuating patterns of movement, and (c) the representation and interactive exploration of the results in order to make interpretations of the findings and further refinement to the simplification and enhancement process. We illustrate our methodology through an analysis example of two different types of tracks, aircraft and pedestrian movement.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2015
Keywords
Visual analysis; trajectories; simplification; thematic enhancement; clustering
National Category
Electrical Engineering, Electronic Engineering, Information Engineering Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:liu:diva-113165 (URN)10.1109/TVCG.2014.2337333 (DOI)000345907200011 ()
Available from: 2015-01-14 Created: 2015-01-12 Last updated: 2017-12-05
Ellegård, K., Vrotsou, K. & Widén, J. (2015). VISUAL-TimePAcTS / energy use: a software application for visualizing energy use from activities performed. In: Jonas Anshelm, Kajsa Ellegård, Jenny Palm, Harald Rohracher (Ed.), Socio-technical perspectives on sustainable energy systems: (pp. 127-145). Linköping: Linköping University
Open this publication in new window or tab >>VISUAL-TimePAcTS / energy use: a software application for visualizing energy use from activities performed
2015 (English)In: Socio-technical perspectives on sustainable energy systems / [ed] Jonas Anshelm, Kajsa Ellegård, Jenny Palm, Harald Rohracher, Linköping: Linköping University , 2015, p. 127-145Chapter in book (Other academic)
Place, publisher, year, edition, pages
Linköping: Linköping University, 2015
Series
Linköping studies in technology and social change ; 2
Keywords
Energiförbrukning, Programvara
National Category
Energy Systems
Identifiers
urn:nbn:se:liu:diva-118914 (URN)978-91-7519-104-1 (ISBN)
Available from: 2015-06-05 Created: 2015-06-05 Last updated: 2015-06-22Bibliographically approved
Vrotsou, K., Ynnerman, A. & Cooper, M. (2014). Are we what we do? Exploring group behaviour through user-defined event-sequence similarity. Information Visualization, 13(3), 232-247
Open this publication in new window or tab >>Are we what we do? Exploring group behaviour through user-defined event-sequence similarity
2014 (English)In: Information Visualization, ISSN 1473-8716, E-ISSN 1473-8724, Vol. 13, no 3, p. 232-247Article in journal (Refereed) Published
Abstract [en]

The study of human activity in space and time is an inherent part of human geography. In order to perform such studies, data on the time use of individuals, in terms of sequence and timing of performed activities, are collected and analysed. A common assumption when analysing individuals’ time use is that groups that exhibit similar background and demographic characteristics also display similarities in how they use their time to structure their daily lives. In this article, we set out to investigate the correctness of such assumptions. We propose a visual analytics process based on sequence similarity measures tailored to event-based data such as performed activity sequences. The process allows an analyst to retrieve similarly behaving records according to user-selected similarity preferences and interactively explore aspects of this similarity in a multiple linked-view environment.

Place, publisher, year, edition, pages
Sage Publications, 2014
Keywords
Event-based data, event-sequences, similarity measures, clustering, activity diaries, time-use data
National Category
Computer and Information Sciences
Identifiers
urn:nbn:se:liu:diva-90151 (URN)10.1177/1473871613477852 (DOI)000337711400004 ()
Available from: 2013-03-20 Created: 2013-03-20 Last updated: 2018-01-11
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-4761-8601

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