Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
SlideShare a Scribd company logo

Second Life as an Experiential Learning Opportunity

•Download as PPTX, PDF•
•
Staci Trekles
Staci Trekles

This document discusses Purdue University Calumet's Second Life initiative and experiential learning opportunities. It outlines several projects using Second Life across different academic disciplines, including creating virtual classrooms, simulations, and lessons. It also addresses some of the challenges of implementing these virtual learning experiences and factors to consider like performance, media integration, and detecting student affective state. The document provides references on related research and concludes by looking towards the future of these types of projects at Purdue and in virtual worlds generally.

1 of 32
Second Life as an Experiential Learning OpportunityComputers and Writing 2010:Virtual Worlds @ Purdue ConferenceMay 21, 2010Slides available: http://slideshare.net/andella
Panel OverviewPurdue University Calumet Campus Second Life Initiative Team:Anastasia Trekles, School of EducationSherrie Kristin, Library and Information ServicesMichael Roller, Computer Graphics TechnologyKim Nankivell, Computer Graphics TechnologyGe Jin, Computer Graphics TechnologyMark Mabrito, English and Philosophy
Objectives of EXL ProgramPresent and describe the intended purpose and application of the construction or activity they have created;Design and implement an activity or construction that meets the supervising staff or faculty member’s needs, and accomplishes his/her expected educational outcomes;Conduct him/herself professionally as a member of a project team;Communicate routinely with supervising faculty/staff, as well as related Subject Matter Experts where appropriate, on the details and status of the project;Demonstrate problem-solving and troubleshooting abilities when appropriate.
From Concept to RealityPurchasing the island and restrictions: What cannot be done on an “educational platform?”Challenges once purchased: Once the island is paid for, how do we do what we want?In a “budget reduction” environment, what is the future for the project?Our approach to the “Experiential Learning” credit adaptation: Why we chose the avenues we did
Factors and Challenges to ImplementationWhat other schools are doingImplementationAlternatives (per Kim)Determining the learner’s affective state
Learning in Virtual Environments and the Student Affective StateVirtual Classroom in Second LifeTraining in Virtual EnvironmentMilitaryHealthcareDisaster & ResponseIntelligent Tutoring SystemEffective human instructors are able to monitor student affective state and tailor their teaching methods to maintain high levels of affect It is difficult to assess the learner’s affective state (motivation, interest, engagement level) in virtual learning environment.
Sensory Channels Related with Affective StateVisual ChannelFacial ExpressionsGesturesAuditory ChannelSpeechPhysiological ChannelRespiration rateHeart rateSkin temperatureElectrocardiography (EEG)Accuracy of affective state detection using facial expressions > 70%
Affective State Detection from Facial ImagesA prototype affective state detection system from single camera image sequences
Face DetectionFace Size Estimation – Face TriangleThe size of eyes and mouthalso can be estimated from face triangle.faceeyes / mouthnothing480Haar feature based face detection(Jones & Viola 2001)640
Image Processing Approaches Used Thresholding
Histogram Equalization
Finding Corners
Convex Hull ApproximationGabor Filter (Gabor Wavelet Trans.)A Gabor filter is a linear filter used in image processing for edge detection. Frequency and orientation representations of Gabor filter are similar to those of human visual system, and it has been found to be particularly appropriate for texture representation and discrimination.Particular Gabor filter responses can help extracting and getting some characteristic features for certain facial expressions (e.g. frowning) at some specific face positions.
Gabor Filters – Face TemplateWe are using 32 feature points in face template, 12 gabors filters with different directions & frequency, generate 384 gabor responses each frame. The 384-vector is used to train system using SVM.
Examples
Broad Scale/Metaverse ApplicationsPedagogical implicationsStandardizationCross-discipline implementationExperimentation and future considerationsApplication to the curriculum
Research in Metaverse ApplicationsResearch Question:What factors should be considered in order to define and establish an accepted set of specifications for which effective avatar applications and architectures can be created and deployed for learners?Research Objectives:Investigate how learners, in various roles and domains, perceive virtualized representations and artifacts (avatars) for interaction.Document the wider educational implications of technology on recall and retention, and how they are created and developed.
Cognitive FactorsPresence and PerceptionGestures and Body Language: Research has shown limitations on behavior cues found in virtual environments have the potential to alter the perception of self and the behavioral interactions between avatars within a virtual world [1][2].Translation Between WorldsRecognition/recall from in-world experiences to out-of-world applicationYee, n., & Ballenson, J.N. (2009). The Difference Between Being and Seeing: The Relative Contribution of Self-Perception and Priming to Behavioral Changes via Digital Self-Representation. Media Psychology, 12:2, 195 – 209.Francheschi, K., Lee, R., Zanakis, S., Hinds, D. (2009). Engaging Group E-Learning in Virtual Worlds. Journal of management Information Systems; vol. 26, no. 1 (pp. 73-100).
Technological FactorsPerformance and StabilityLatency can alter perception and presence and negatively affect collaboration between participants [3]. Media Integration for SimulationOptimization methods/algorithms for artifacts to ensure both believability and accuracy within the interactive construct or processEdirisinga, P., Nie, M., Pluciennik, M., Young, R. (2009). Socialisation for Learning at a Distance in a 3-D Multi-user Virtual Environment. British Journal Educational Technology; vol. 40, no. 3 (pp. 458-479).
MethodologyMixed-Method Approach:Cognitive Factors Qualitative measures on how learners view online learning environments and avatar representations (learning styles, learner perceptions, self and group presence and interaction)Technical FactorsQualitative measures on performance, stability, and compatibility with media and networked file systems (latency, optimization, performance)
Expected OutcomeDeeper understanding of cognitive and technological factors associated with virtualized learning environmentsSpecification for designing, developing and incorporating effective avatar technologies within virtual environments specifically for the improvement of learning and interaction
Projects in the Content AreasEnglish and WritingEducationComputer Graphics TechnologyNursingLibrary
English WritingENGL 43500: Designing Virtual WorldsComponent to Online Certificate in Writing for Interactive Media.Students create design proposals for SL Sims, related to business, training, entertainment, etc. Students explore communication/collaboration in a virtual world.Students may be able to continue beyond course with a “virtual internship” assisting in creating course content for SL.
English Writing“Avatar Journal” project (cross class project-Fall 10 or Spring 11)Students explore avatar creation as identity.Maintain a blog from avatar’s perspective to parallel and document experiences in-world.Students create and showcase artifacts (interactive objects within SL) defining their SL experiences from avatar’s perspective.Examine ways in which the metaverse can be used for primary/secondary research.Used as basis for future writing and research projects in other classes.
Instructional Technology and EducationEDCI 56600: Hypermedia Application in EducationGraduate students explore Second Life and identify strengths, weaknesses, and potential uses in educational environmentsDiscussion of all types of applications including industry, healthcare, K-12, and higher educationEDCI 59100: Advanced Multimedia DesignStudents are tasked to build a classroom simulation for student teachers to practice presentation skills – first build will take place this summerEDCI 58900: Virtual Worlds in EducationGraduate credit course for K12 teacher license renewalIntroduces teachers to virtual worlds and asks them to build a lesson plan and learning objects
Special EducationDisabilities groups: Second Life sites like Virtual Ability Island and the PATINS Project provide information and resourcesAutism: Virtual worlds, like video games, have often been favored by autistic people, especially children, as a means of self-expression and communicationADHD: Virtual worlds are engaging; students with ADHD and other learning disabilities can connect with subjects in unique ways to visualize, analyze, and to use as story- or research-starters
Computer Graphics TechnologyProject – comparing face-to-face to virtual teaching with facial expression modelsHow to detect the student’s and instructor’s expression and body languageNot limited to SL, in fact may not work best in SL
Nursing EducationPharmacokinetics course very interested in simulation possibilities for training nursing students in drug logging, dispensing, and administrationReading labels, checking orders on a patient chart, measuring drug intake and outputProcesses for setting up titrations and mixing insulinsSimulated administrations that invoke events (patient vitals change, stabilization, death)Planning still in process; may become a simulation programmed outside of Second Life
Library Media ServicesPlanned Second Life implementation of Library at Purdue Calumet includes:Access to databases and informational repositories available through the Library, even for those who are off-campusA virtual walk-through tour of the real Library to familiarize students with the space and where items are located
Looking to the Future…What are the next steps for… Purdue University Calumet?Courses, activities, and experiential learning opportunities for students in virtual worlds? Research into the efficacy and implications of virtual world technology for teaching and learning?
ReferencesAnnetta, L., M. Klesath, and S. Holmes. 2008. V-learning: How gaming and avatars are engaging online students. Innovate 4 (3). Retrieved February 19, 2010, from http://www.innovateonline.info/index.php?view=article&id=485. Beard, L., Wilson, K., Morra, D., & Keelan, J. (2009). Journal of Medial Internet Research, 11(2). Retrieved February 19, 2010, from http://www.jmir.org/2009/2/e17/HTML. Bronack, S., Sanders, R., Cheney, A., Riedl, R., Tashner, J., Matzen, N. (2008). Presence pedagogy: Teaching and learning in a 3D virtual immersive world. International Journal of Teaching and Learning in Higher Education, 20(1). 59-69.Cheal, C. (2009). Student perceptions of a course taught in Second Life. Innovate 5(5). Retrieved February 19, 2010, from http://www.innovateonline.info/index.php?view=article&id=692. Cheong, D.U., Yun, S. & Chollins, C. (2009). Is Second Life effective for pre-service teachers’ teaching practice?. In I. Gibson et al. (Eds.), Proceedings of Society for Information Technology & Teacher Education International Conference 2009 (pp. 1418-1421). Chesapeake, VA: AACE.
ReferencesCheong, D.U., Yun, S. & Chollins, C. (2009). Is Second Life effective for pre-service teachers’ teaching practice?. In I. Gibson et al. (Eds.), Proceedings of Society for Information Technology & Teacher Education International Conference 2009 (pp. 1418-1421). Chesapeake, VA: AACE.Collins, F. (2008). Digital selves: Preparing graduates for the virtual workplace. In Proceedings of World Conference on Educational Multimedia, Hypermedia and Telecommunications 2008 (pp. 5853-5858). Chesapeake, VA: AACE.Diener, S., Windsor, J., Bodily, D. (2009, May 9). Design and Development of Medical Simulations in Second Life and OpenSim. Paper Presented at the EDUCAUSE Australasia Conference, Perth, Australia. Gee, J. P. (2005). Learning by design: Good video games as learning machines. E-Learning, 2(1). 5-16. Retrieved July 12, 2005, from http://www.wwwords.co.uk/pdf/validate.asp?j=elea&vol=2&issue=1&year=2005&article=2_Gee_ELEA_2_1_web.

More Related Content

Second Life as an Experiential Learning Opportunity

  • 1. Second Life as an Experiential Learning OpportunityComputers and Writing 2010:Virtual Worlds @ Purdue ConferenceMay 21, 2010Slides available: http://slideshare.net/andella
  • 2. Panel OverviewPurdue University Calumet Campus Second Life Initiative Team:Anastasia Trekles, School of EducationSherrie Kristin, Library and Information ServicesMichael Roller, Computer Graphics TechnologyKim Nankivell, Computer Graphics TechnologyGe Jin, Computer Graphics TechnologyMark Mabrito, English and Philosophy
  • 3. Objectives of EXL ProgramPresent and describe the intended purpose and application of the construction or activity they have created;Design and implement an activity or construction that meets the supervising staff or faculty member’s needs, and accomplishes his/her expected educational outcomes;Conduct him/herself professionally as a member of a project team;Communicate routinely with supervising faculty/staff, as well as related Subject Matter Experts where appropriate, on the details and status of the project;Demonstrate problem-solving and troubleshooting abilities when appropriate.
  • 4. From Concept to RealityPurchasing the island and restrictions: What cannot be done on an “educational platform?”Challenges once purchased: Once the island is paid for, how do we do what we want?In a “budget reduction” environment, what is the future for the project?Our approach to the “Experiential Learning” credit adaptation: Why we chose the avenues we did
  • 5. Factors and Challenges to ImplementationWhat other schools are doingImplementationAlternatives (per Kim)Determining the learner’s affective state
  • 6. Learning in Virtual Environments and the Student Affective StateVirtual Classroom in Second LifeTraining in Virtual EnvironmentMilitaryHealthcareDisaster & ResponseIntelligent Tutoring SystemEffective human instructors are able to monitor student affective state and tailor their teaching methods to maintain high levels of affect It is difficult to assess the learner’s affective state (motivation, interest, engagement level) in virtual learning environment.
  • 7. Sensory Channels Related with Affective StateVisual ChannelFacial ExpressionsGesturesAuditory ChannelSpeechPhysiological ChannelRespiration rateHeart rateSkin temperatureElectrocardiography (EEG)Accuracy of affective state detection using facial expressions > 70%
  • 8. Affective State Detection from Facial ImagesA prototype affective state detection system from single camera image sequences
  • 9. Face DetectionFace Size Estimation – Face TriangleThe size of eyes and mouthalso can be estimated from face triangle.faceeyes / mouthnothing480Haar feature based face detection(Jones & Viola 2001)640
  • 10. Image Processing Approaches Used Thresholding
  • 13. Convex Hull ApproximationGabor Filter (Gabor Wavelet Trans.)A Gabor filter is a linear filter used in image processing for edge detection. Frequency and orientation representations of Gabor filter are similar to those of human visual system, and it has been found to be particularly appropriate for texture representation and discrimination.Particular Gabor filter responses can help extracting and getting some characteristic features for certain facial expressions (e.g. frowning) at some specific face positions.
  • 14. Gabor Filters – Face TemplateWe are using 32 feature points in face template, 12 gabors filters with different directions & frequency, generate 384 gabor responses each frame. The 384-vector is used to train system using SVM.
  • 16. Broad Scale/Metaverse ApplicationsPedagogical implicationsStandardizationCross-discipline implementationExperimentation and future considerationsApplication to the curriculum
  • 17. Research in Metaverse ApplicationsResearch Question:What factors should be considered in order to define and establish an accepted set of specifications for which effective avatar applications and architectures can be created and deployed for learners?Research Objectives:Investigate how learners, in various roles and domains, perceive virtualized representations and artifacts (avatars) for interaction.Document the wider educational implications of technology on recall and retention, and how they are created and developed.
  • 18. Cognitive FactorsPresence and PerceptionGestures and Body Language: Research has shown limitations on behavior cues found in virtual environments have the potential to alter the perception of self and the behavioral interactions between avatars within a virtual world [1][2].Translation Between WorldsRecognition/recall from in-world experiences to out-of-world applicationYee, n., & Ballenson, J.N. (2009). The Difference Between Being and Seeing: The Relative Contribution of Self-Perception and Priming to Behavioral Changes via Digital Self-Representation. Media Psychology, 12:2, 195 – 209.Francheschi, K., Lee, R., Zanakis, S., Hinds, D. (2009). Engaging Group E-Learning in Virtual Worlds. Journal of management Information Systems; vol. 26, no. 1 (pp. 73-100).
  • 19. Technological FactorsPerformance and StabilityLatency can alter perception and presence and negatively affect collaboration between participants [3]. Media Integration for SimulationOptimization methods/algorithms for artifacts to ensure both believability and accuracy within the interactive construct or processEdirisinga, P., Nie, M., Pluciennik, M., Young, R. (2009). Socialisation for Learning at a Distance in a 3-D Multi-user Virtual Environment. British Journal Educational Technology; vol. 40, no. 3 (pp. 458-479).
  • 20. MethodologyMixed-Method Approach:Cognitive Factors Qualitative measures on how learners view online learning environments and avatar representations (learning styles, learner perceptions, self and group presence and interaction)Technical FactorsQualitative measures on performance, stability, and compatibility with media and networked file systems (latency, optimization, performance)
  • 21. Expected OutcomeDeeper understanding of cognitive and technological factors associated with virtualized learning environmentsSpecification for designing, developing and incorporating effective avatar technologies within virtual environments specifically for the improvement of learning and interaction
  • 22. Projects in the Content AreasEnglish and WritingEducationComputer Graphics TechnologyNursingLibrary
  • 23. English WritingENGL 43500: Designing Virtual WorldsComponent to Online Certificate in Writing for Interactive Media.Students create design proposals for SL Sims, related to business, training, entertainment, etc. Students explore communication/collaboration in a virtual world.Students may be able to continue beyond course with a “virtual internship” assisting in creating course content for SL.
  • 24. English Writing“Avatar Journal” project (cross class project-Fall 10 or Spring 11)Students explore avatar creation as identity.Maintain a blog from avatar’s perspective to parallel and document experiences in-world.Students create and showcase artifacts (interactive objects within SL) defining their SL experiences from avatar’s perspective.Examine ways in which the metaverse can be used for primary/secondary research.Used as basis for future writing and research projects in other classes.
  • 25. Instructional Technology and EducationEDCI 56600: Hypermedia Application in EducationGraduate students explore Second Life and identify strengths, weaknesses, and potential uses in educational environmentsDiscussion of all types of applications including industry, healthcare, K-12, and higher educationEDCI 59100: Advanced Multimedia DesignStudents are tasked to build a classroom simulation for student teachers to practice presentation skills – first build will take place this summerEDCI 58900: Virtual Worlds in EducationGraduate credit course for K12 teacher license renewalIntroduces teachers to virtual worlds and asks them to build a lesson plan and learning objects
  • 26. Special EducationDisabilities groups: Second Life sites like Virtual Ability Island and the PATINS Project provide information and resourcesAutism: Virtual worlds, like video games, have often been favored by autistic people, especially children, as a means of self-expression and communicationADHD: Virtual worlds are engaging; students with ADHD and other learning disabilities can connect with subjects in unique ways to visualize, analyze, and to use as story- or research-starters
  • 27. Computer Graphics TechnologyProject – comparing face-to-face to virtual teaching with facial expression modelsHow to detect the student’s and instructor’s expression and body languageNot limited to SL, in fact may not work best in SL
  • 28. Nursing EducationPharmacokinetics course very interested in simulation possibilities for training nursing students in drug logging, dispensing, and administrationReading labels, checking orders on a patient chart, measuring drug intake and outputProcesses for setting up titrations and mixing insulinsSimulated administrations that invoke events (patient vitals change, stabilization, death)Planning still in process; may become a simulation programmed outside of Second Life
  • 29. Library Media ServicesPlanned Second Life implementation of Library at Purdue Calumet includes:Access to databases and informational repositories available through the Library, even for those who are off-campusA virtual walk-through tour of the real Library to familiarize students with the space and where items are located
  • 30. Looking to the Future…What are the next steps for… Purdue University Calumet?Courses, activities, and experiential learning opportunities for students in virtual worlds? Research into the efficacy and implications of virtual world technology for teaching and learning?
  • 31. ReferencesAnnetta, L., M. Klesath, and S. Holmes. 2008. V-learning: How gaming and avatars are engaging online students. Innovate 4 (3). Retrieved February 19, 2010, from http://www.innovateonline.info/index.php?view=article&id=485. Beard, L., Wilson, K., Morra, D., & Keelan, J. (2009). Journal of Medial Internet Research, 11(2). Retrieved February 19, 2010, from http://www.jmir.org/2009/2/e17/HTML. Bronack, S., Sanders, R., Cheney, A., Riedl, R., Tashner, J., Matzen, N. (2008). Presence pedagogy: Teaching and learning in a 3D virtual immersive world. International Journal of Teaching and Learning in Higher Education, 20(1). 59-69.Cheal, C. (2009). Student perceptions of a course taught in Second Life. Innovate 5(5). Retrieved February 19, 2010, from http://www.innovateonline.info/index.php?view=article&id=692. Cheong, D.U., Yun, S. & Chollins, C. (2009). Is Second Life effective for pre-service teachers’ teaching practice?. In I. Gibson et al. (Eds.), Proceedings of Society for Information Technology & Teacher Education International Conference 2009 (pp. 1418-1421). Chesapeake, VA: AACE.
  • 32. ReferencesCheong, D.U., Yun, S. & Chollins, C. (2009). Is Second Life effective for pre-service teachers’ teaching practice?. In I. Gibson et al. (Eds.), Proceedings of Society for Information Technology & Teacher Education International Conference 2009 (pp. 1418-1421). Chesapeake, VA: AACE.Collins, F. (2008). Digital selves: Preparing graduates for the virtual workplace. In Proceedings of World Conference on Educational Multimedia, Hypermedia and Telecommunications 2008 (pp. 5853-5858). Chesapeake, VA: AACE.Diener, S., Windsor, J., Bodily, D. (2009, May 9). Design and Development of Medical Simulations in Second Life and OpenSim. Paper Presented at the EDUCAUSE Australasia Conference, Perth, Australia. Gee, J. P. (2005). Learning by design: Good video games as learning machines. E-Learning, 2(1). 5-16. Retrieved July 12, 2005, from http://www.wwwords.co.uk/pdf/validate.asp?j=elea&vol=2&issue=1&year=2005&article=2_Gee_ELEA_2_1_web.
  • 33. ReferencesGraetz, K. A. (2006). The psychology of learning environments. In D. Oblinger (Ed.), Learning Spaces (pp. 6.1-6.14). Boulder, CO: EDUCAUSE. Retrieved July 16, 2007, from http://www.educause.edu/learningspaces. Hobbs, M., Brown, E., & Gordon, M. (2006). Using a virtual world for transferable skills in gaming education. ITALICS, 5(3). Retrieved February 19, 2010, from http://www.doaj.org/doaj?func=fulltext&passMe=http://www.ics.heacademy.ac.uk/italics/vol5iss3/hobbsbrowngordon.pdf. Jarmon, L., Traphagan, T., and Mayrath, M. (2008). Understanding project-based learning in Second Life with a pedagogy, training, and assessment trio. Educational Media International, 45(3).157 - 176.Ke, F. (2008). Computer games application within alternative classroom goal structures: Cognitive, metacognitive, and affective evaluation. Education Technology Research Development, 56. 539-556.
  • 34. ReferencesMesko, B. (2007, June 17). Top 10: Virtual medical sites in Second Life. ScienceRoll. Retrieved February 19, 2010, from http://scienceroll.com/2007/06/17/top-10-virtual-medical-sites-in-second-life/.Moreno, R., & Mayer, R. (2007). Interactive multimodal learning environments. Educational Psychology Review, 19. 309-326.Moschini, E. (2006). Designing for the smart player: Usability design and user-centered design in game-based learning. Digital Creativity, 17(3). 140-147.Pisha, B., & Stahl, S. (2005). The promise of new learning environments for students with disabilities. Intervention in School and Clinic, 41(2). 67-75. Rice, J. W. (2007). New media resistance: Barriers to implementation of computer video games in the classroom. Journal of Educational Multimedia and Hypermedia, 16(3). 249-261.

Editor's Notes

  1. Staci: This is a course in the online certificate in writing for interactive media, which I created two years ago and consists of 5 courses that feature writing for informational and narrative interactive media and Web usability. 435 is new and is the only course that gives students experience in working in/designing for a virtual world--in this case, SL. If all goes well, I anticipate that I might be able to cull a couple of good students from this class to work with me further doing independent studies, assisting me with some of the projects I might be working on.Some of the tasks students will be charged with in this course include: writing a design proposal for an original SL Sim; exploring various venues for communicating with their avatar—i.e., conferences, meetings, and such; explore business- education- and/or entertainment-related Sims; explore career opportunities in SL.
  2. Staci: This project still is under development but here is what I envision it becoming: The purpose of this project is for students new to SL to chronicle in a journal their “life experiences” as an avatar from birth (when they first create their avatar) until some future development point in the avatar’s life (in rl, probably a semester or so). The journal will be kept at an online blog and possibly also in-world as notecards to be shared with other participants. The journal is meant to be written in the avatar’s voice.Some of the journal entries will be self-initiated and some will be loosely suggested, involving some sort of corresponding exploration/task in SL. Initially, the emphasis will be on simple narration/description, since the avatar is young and exploring his/her environment. Eventually, the avatar will be challenged to write more expository pieces, progressing eventually to writing longer, more analytical, research-based entries—for example, researching a stance in favor of some in-world (or real-world) debate or policy struggle, theorizing about aspects of the virtual experience. As the avatar becomes more rhetorically challenged in the journal, it will be expected to become better versed and more sophisticated in interacting with SL and other avatars—for example, conducting Sim-based research, attending a workshop/conference, volunteering to help with an in-world event, constructing simple objects, maybe even giving a presentation or participating in a poster session in-world, exploring employment opportunities in-world, etc.In addition to the journal, I’m envisioning the avatar also producing artifacts that represent their experiences in different modalities, other than text, which also can be stored and displayed for other journal participants to see in-world—for example, podcasts (where we actually get to hear the avatar, not the student), a vlog, digital artwork, or whatever the avatar really thinks appropriate using different media and that somehow ties in with the experiences they are writing about. As students may revise their journal, they also will be invited to think about how to revise/repurpose their in-world objects to make the connection between the writing and the in-world representation of it.