An Online Collaboration Model for the Distance Education of Cartography

Transcription

1 An Online Collaboration Model for the Distance Education of Cartography Kate Sherren and Manolya Kavakli School of Science and Technology Charles Sturt University, Wagga Wagga NSW, Australia Abstract This paper discusses the characteristics of traditional cartography education in higher education institutes and describes an online collaboration model for the distance education of cartography. Our aim is to use this model in the distant education sessions of GIS courses of Charles Sturt University, Australia. In this paper, given the evidence from research studies in different disciplines, we discuss the advantages of an online collaboration model versus a traditional model in the distance education of cartography, and propose a model for how it can be done. Keywords: cartography distance education online collaboration forums Charles Sturt University Introduction Cartography, as an area of study, is located between art and science and is most commonly taught as a small component of either Geographic Information Systems (GIS) or the surveying sciences. Despite the unarguable power of maps as a communication tool, very little importance is placed on teaching the art, as well as the science, in such courses. This is due both to the scientific focus of teaching staff and the priorities of students learning new, custom software in spatial science coursework. The software must be mastered before it can be used creatively. The creative use of GIS software to produce quality cartographic output is even more difficult for distance education (DE) cohorts. The aim of this paper is to discuss how we can exploit online facilities to respond to the demands of the student studying cartography at a distance. There are several environments available, such as Active Worlds and Microsoft NetMeeting, which have been heavily tested in traditionally creative fields such as architecture. Both synchronous and asynchronous approaches are proposed for use in virtual one-on-one teacher-student consultations, and group critique sessions. It is expected that these approaches will produce positive learning outcomes by increasing DE student involvement in the subject, increasing student exposure to other students designs and opinions, and allowing for intermediary consultation before final assessment is made. To design a system to address the inequities inherent in learning cartography by DE, we must investigate the history of cartographic education, before and after the advent of computers. We will assess the tools currently available to DE providers and their pedagogical uses. Technical requirements and limitations must also be discussed. Finally, the online collaboration literature must be reviewed, and from this will be determined a set of control models that we can adapt for our needs. 123

2 Kate Sherren and Manolya Kavakli An Online Collaboration Model for the Distance Education Cartographic Education Traditional cartography subjects cover quantitative topic areas such as coordinate systems, map projections, scale, data classification, feature generalisation and methods of thematic mapping (Slocum 1999, Dent 1999). In the pre-computer era, cartographers would also learn details about the printing process, such as the production of colour separates and how large-format plotters and printing presses operate. The manual skills of scribing and lettering were what made cartography a vocation that required an aptitude as well as an interest, and prospective apprentices were tested for a steady hand and a good eye. Output from early GIS software was nowhere close to threatening the dominance of manually produced maps. However, the addition of WYSIWYG (what you see is what you get) computer technology to GIS software, and the lowering of the cost of high quality plotters, did cause digital production to replace manual systems. User-friendly GIS software tools enabled quick map production, even by non-specialists, and map design suffered from the use of map templates. Current cartography teaching retains the quantitative theory listed above, but printing theory has been replaced by animation, internet mapping and multimedia. Cartographic design is often addressed only in passing. At Charles Sturt University (CSU), cartography education is a part of GIS and environmental management courses based in the Faculty of Science and Agriculture. These courses are available at both bachelors and graduate levels, and all of the courses have a DE cohort larger than the oncampus one. Only two subjects currently cover cartographic design theory; the introductory GIS subject contains a week on mapping, and one dedicated subject called Cartography and Data Visualisation is also offered. Map aesthetics are not assessed in the first, only completeness based on the presence of all map fundamentals. In the second, students complete several cartography assignments in which graphic design is the focus and it is for use in this subject that online collaboration is proposed. Staff members in the Faculty of Science and Agriculture are accustomed to teaching science rather than the creative arts, and do not tend to use online collaborative methods that are common in creative fields such as architecture. Science teaching is characterised by the ability to easily assess a correct answer, whereas creative arts assessment is qualitative. Students learn to produce and recognize good design gradually, by seeing large numbers of examples and getting feedback from the lecturer. Internal students are able to get that interaction from lecturers during practicals and tutorials, and also learn from the comments given to their peers. Distance students have no way to experience an equivalent iterative design experience, and are not exposed to as many examples of design before they submit assessment tasks. Due to staffing and course changes, the last offering of a dedicated cartography subject by DE mode at CSU was in the autumn session of 2001, where 23 students undertook the subject, 10 by DE and 13 internally. The skills of the external cohort varied more than those of internals who were, in this case, all school-leavers. DE student outcomes were markedly lower than the internal students, save for two who worked in GIS departments already, and also required more resubmissions due to inadequate work than did the internals. This experience led to research of methods of ameliorating the learning experience for all students before the next external offering. Distance Education Distance education has, by necessity, been an environment where new technology is trialed. Many digital learning software environments have been developed to facilitate the interaction between geographically distant learners and teachers. The pedagogy of DE relies on such software, such as Blackboard Learning Systems, HP Virtual Classroom, and Lotus Learning Space, to store and deliver course materials and provide common forum access. At CSU, a custom environment has been programmed that serves these purposes, but the only two-way interaction available is on 124

3 An Online Collaboration Model for the Distance Education Kate Sherren and Manolya Kavakli online forums. Large files can be attached to online forums and these files can be of any kind; image, text or application. A benefit of these forums is that all students enrolled in a subject whether internal or external, can be given access to a subject s forum. Students can also contribute anonymously, so other students do not know who they are, but the instructor is able to find out. There are many universities that teach cartography in Australia, but few of them do so by DE. RMIT offers a number of cartography courses in flexible modes, notably in Multimedia Cartography, and uses Blackboard software to supplement face-to-face interaction with students (Cartwright, 2001). The University of Southern Queensland offers surveying and land information science by DE (McDougall, Young and Apan, 2003). Curtin University, in Western Australia, offers cartography as a component of its surveying and GIS degrees. Though Curtin has developed a computer mediated communication system for their DE students, the system does not include graphical collaborative functions such as would be helpful for the visual arts. The terms of reference of the International Cartographic Association (ICA) Standing Commission on Education and Training includes the promotion of the DE teaching of cartography via the internet. However, the authors are not aware of any interactive teaching environments that might replace the one-onone tutorial consultation. There are creative courses, such as graphic design, taught by distance at CSU, and these use only forum critiques as an online collaborative environment. They rely more on compulsory residential schools to equalise the students experience. During residential schools, distance students in a subject gather at a campus for an intensive period of lectures and practical work. Not all subjects have them, and in those that do, they can be optional or compulsory. At CSU, budgetary limitations common to all Australian universities have created an environment in which expensive residential schools are being phased out. In addition, course marketers have found that students avoid enrolling in courses that have obligatory residential schools, and this has also contributed to a roll-back in res school offerings. It is possible that more interactive online methods can make up for this loss. Online Collaboration Online collaboration was developed to allow geographically separated designers to work together. Nowadays, shared PCs and shared window systems allow ordinary applications to be the focus of cooperative work. Most of the shareware tools require special collaboration-aware applications to be written. Amsterdam Conversation Environment (Dykstra & Carasik, 1991) was one of the pioneering examples of communication shareware. It was developed from the bulletin board concept, but worked more like a shared hypertext. The structure of links and cross references allowed users to have sub-conferences and digressions, to annotate each other s messages, and to post follow-on messages. TeamWorkStation (Ishii & Miyake, 1991) was an interesting example of shared work surfaces where the participants could write on a sheet of paper on their desktop, which would then be filmed from above. It was used for the remote teaching of Japanese calligraphy. In this system participants also had a face-to-face video link. Another system used a headset telephone and a shared drawing environment via ROCOCO Sketchpad (Scrivener et al., 1993). They identified the requirements for shared drawing systems as follows: All participants should see the marks and gestures without much delay, Users should be able to rapidly switch between drawing, writing and gesturing, The marking and gesturing should be simultaneously visible in the same environment, and Familiar mechanisms for drawing space activity should be preserved. Mazijoglou et al. (1994) conducted another series of experiments with fifteen pairs of subjects with the ROCOCO Sketchpad. They have integrated the shared drawing surface with a shared view 125

4 Kate Sherren and Manolya Kavakli An Online Collaboration Model for the Distance Education system and observed the extent to which the drawing surface supported the pair by communication and collaboration. They also watched how the group dynamics were influenced by the available resources. Mazijoglou et al. (1994) argued that people who will work together must differ in skills and expertise. Saad and Maher (1995) and Kalay and Squin (1995) focused on technical issues of sharing information. Kimura, Komatsu and Watabe (1995) developed the Interapplicational Collaborative Design Systems (ICDS) to merge data from the many participants in the planning process. Maher and Cicognani (1997) conducted two design sessions, each with two designers. They observed the dynamics of design semantics during the session and the design semantics stored in the final design document. The participants used InPerson for video conferencing. Greenberg and Roseman (1998) tested the useability of TeamWave Workplace, where virtual rooms were available for users for individual and group working. They also aimed to ease the difficulties in moving between individual and shared work in real-time online meetings. Kavakli and Petuhova (1999) conducted a series of experiments to explore the team behaviour in design collaboration and its effect on design representation in three different collaboration models: a) Collaboration of novices in the same discipline; b) Collaboration of professionals from different disciplines; and c) Collaboration of professionals in the same discipline. They used the NetMeeting environment as the collaboration software and videotaped the participants for the later analyses (Petuhova, 1999). They found similar characteristics in team behaviour at a distance in three different collaboration models in the computer supported collaborative design sessions. Cagdas et al. (2000) developed a Virtual Design Studio between Istanbul Technical University and University of Sydney. This Virtual Design Studio allowed architectural design students to collaborate at a distance to design an Olympic village for Sydney 2000 Olympic Games. Students used ActiveWorlds, a virtual reality program, to design the Olympic village. ActiveWorlds also gave them an opportunity to represent themselves by using avatars and explore the Olympic village they had just designed. The students used mostly ActiveWorld s chat facilities to collaborate with their distant partners. They also used the NetMeeting environment for sketching on the Whiteboard and videoconferencing for a face-to-face contact. Technical Limitations Kavakli and Petuhova (1999) reported that computer supported collaborative design, as opposed to individual design process, requires the following hardware, software and communication links for each participant: a) Personal computer b) Internet link c) Collaboration software capable of sharing workspaces and programs, text chatting and sketching in a common environment d) Specialty design software (such as ArcView, but only 1 machine must have this) e) Audio link f) Video link The hardware that is essential for setting up online collaboration is basically a computer and a modem or other internet connection per participant. Other peripherals such as microphones and video cameras are preferable, but are only feasible if all participants are on fast internet connections, which cannot be assumed in DE in Australia. We do not want students to have to 126

5 An Online Collaboration Model for the Distance Education Kate Sherren and Manolya Kavakli invest in new peripherals for this one design subject in their degree, so the use of sound and video cannot be assumed. Our model must be independent of this. The software to be used for online collaboration in education must be free or not very costly, must be able to run on a number of operating systems, and have a small footprint (i.e. they do not take up much space on the computer). Microsoft s Active Worlds, which was used in the design work of Cagdas et al. (2000) on the Sydney Olympic Village, is strongly immersive, using avatars and 3D virtual reality to bring designers together in a space and move things in that space. This perspective would be very beneficial in architecture, where design can begin from an arrangement of primitive shapes and then be refined, but it is not necessary in 2D cartography. Microsoft s NetMeeting, however, is a generic product that is supplied with the Windows 2000 operating system, and allows for synchronous audio, video, whiteboard sketching, file transfer and shared program access. Scrivener et al. (1993) noted that an integration of voice, drawing and gestures in a common environment are necessary in order to create an adequately immersive collaboration session. These needs are well served by the windowing environments discussed above. However, time delay caused by slow internet connection can negatively affect the immersivity by removing the coincidence of video, drawing, speech and text. Though mobile phone use is on the increase in Australia, regional Australia still does not have reliable service and this is where many of CSU s DE students reside. We cannot assume mobile service, and therefore, with most home internet users only having one phone line, it is impossible for them to speak on the phone and work online. Collaboration Control Models There are two major types of online collaboration types: synchronous and asynchronous. In asynchronous collaboration, such postings on forums, no control mechanism is required as contributions are posted as they arrive. Sometimes this is very quickly, mimicking synchronous communication, but often the delay is much longer. Synchronous collaboration requires that all participants are on a live connection and are theoretically able to contribute simultaneously. In such collaboration, some model must be adopted to control the order of events such as who has current editing rights of the shared material. The only exception is in synchronous chat modes, where many users may type at the same time, but their text is posted only when they commit to send their message. These chat participants are synchronously linked, but no control is required. Condon (1993) suggests various collaboration control models named after different socio-political regimes, but such a classification unavoidably involves the debatable issue of the interpretation of these regimes. For this reason, a different classification and naming of the 3 major types of Condon s collaboration control schemes will be used here, namely 1) hierarchical, 2) egalitarian, and 3) rule-based. In a hierarchical collaboration control scheme the team members choose one of the participants as the authority who controls and directs the collaboration session. The authority has the privilege of granting the control of the mouse or permission to speak. A hierarchical model is recommended in the following cases: when the topic of the collaboration and discussion is the design of one of the participants (e.g. the architect in a team of engineers designing a house); if one of the participants is a well-accepted expert in the field under consideration (e.g. in DE: the teacher); or if there exists a natural hierarchy between the participants due to difference of age or position (e.g. when the owner of the company has a meeting with his distant employees). 127

6 Kate Sherren and Manolya Kavakli An Online Collaboration Model for the Distance Education In an egalitarian control scheme all participants are given equal priority in the collaborative work. The priorities are arranged by spontaneous request of the participants. This type of control should be preferred in the following situations: in brainstorming situations (e.g. in cases where the participants should be encouraged towards maximum creativity); during short review sessions; or when a hierarchical order between the team members can not or should not be made due to some other reason. In a rule-based control system, the computer system itself arranges the priorities in accordance with a set of rules. One example of an appropriate rule might be the rotational assignment of priorities to each participant for a preset period. This control scheme seems to be the most appropriate one for the following cases: when the participants do not sufficiently know each other; when the participants are not sufficiently acquainted with collaborative online learning; when the approval of each participant with respect to some topic is desired or has to be assured; or when it is supposed that this scheme will guarantee maximum satisfaction of the participants. Online Collaboration Model for Cartography Education Students of the CSU Bachelor of Science (Spatial Science) are very computer literate, learning system administration, programming, and web design through their course. This technologicallyaware cohort will be used to trial the use of collaborative design environments in an advanced cartography subject to be offered to second year students starting in Autumn of It is envisaged that two different types of collaboration will be tested; one-on-one consultations between teacher and student, and group critiques and discussions. Asynchronous forum communication will be used in addition to these synchronous methods for this offering. Asynchronous Interaction Environment Asynchronous collaboration will be performed using CSU s online forum network. This interaction will involve students sharing their practical output on the forum for the purposes of critique from the other students and the lecturer. There may be some incentive given for the participation of other students, such as the awarding of participation marks, to ensure that each student both posts their work and gives some criticism throughout the term. The desirable characteristics for this interaction are the ability to attach files such as JPEG, a common output from graphics packages, and participant anonymity. There is no need for this collaboration to be synchronous, and existing frameworks will meet the above needs adequately. Synchronous Interaction Environment However, synchronous interaction is required for the case of one-on-one tutorials or consultations between student and lecturer. In these cases, the learning experience derives from the immediacy of the response. The software chosen to undertake this trial is Microsoft NetMeeting, which is available free on the internet and also comes bundled with all Microsoft operating systems. It includes the sharing of software, a whiteboard drawing environment, and chat functionality. In order to use the data, chat and whiteboard functions of NetMeeting, both users require at least: a Pentium 90 processor with 24 MB of RAM (P133 with 32 MB is best); 14 MB of free hard disk space; and a 56K modem. Only one of the computers needs to have the target software loaded in this case ESRI s ArcView 3.2 in order for the system to function. 128

7 An Online Collaboration Model for the Distance Education Kate Sherren and Manolya Kavakli In order to contact the lecturer, students must know the lecturer s IP (internet protocol) address. This information, along with instructions for software use, can be supplied in the course materials. The lecturer is able to decide their availability to support requests, by setting their NetMeeting to Do Not Disturb, the digital equivalent of a busy signal. Answering such a call does not make either machine vulnerable. However, allowing others to control shared programs will make the shared files vulnerable until the owner of the clicks on the screen to retrieve control. It is envisaged that these consultations will not be compulsory, but will be performed as requested by the students. It is also predicted that this technology may prove useful for instructing students about GIS analysis procedures, or any other technical skill, as the student can watch the teacher performing it on their machine. Instructional Control Model None of the control models shown so far meets our needs for a collaborative model for teaching cartography. For this reason, a fourth model will be proposed here to fill that niche. This new model is an instructional model based on Condon s (1993) hierarchical and egalitarian models. The hierarchical model is a natural fit, for the fact that there is a definite expert in the form of the subject lecturer. However, in one-on-one consultations, it is the student who requests information or help, who shares their work and with whom the default control of the program resides. The instructional control model we propose for one-on-one consultations is where the student has control, but by making a call agrees to transfer the control of the program to the lecturer when it is requested. This model would not be used if the sessions involved groups; in such cases the lecturer must be able to control the activity to ensure the collaboration is organized and efficient, also meaning that it may have to be the lecturer s computer that is shared. This obviously involves considerable risk management. Pilot Studies Several tests were undertaken to determine the feasibility of sharing complex GIS and drawing programs over the Internet using NetMeeting. Of primary concern was whether the speed of data transmission using 56K modems at the student end would allow for a realistic sense of interaction. One DE student, located in Blackheath, in the Blue Mountains of Australia, was asked and agreed to participate in a trial of the system. His computer system complied with the specifications required. He opened an ArcView window and dialed the lecturer, opening both a chat session, and sharing his ArcView window. Figure 1 shows how that shared session looked on the lecturer s machine while under the control of the student. It can be seen that there are two dark boxes visible over top of the ArcView session. These boxes showed the locations of the chat and NetMeeting boxes on the student s machine. In a real session, the three windows (ArcView, Chat and NetMeeting) would have to be tiled without overlap on the student s machine so that the lecturer sees the entire shared window without obstruction. In this mode, it was possible to watch the student perform actions on the view, changing colours and font sizes, though there was a slight time delay. It would be necessary in a real session to act slowly by typing in the chat environment what you were about to do and then doing each step deliberately in the shared program or whiteboard. When the lecturer took control of the program, the dark boxes disappeared (though still flickered occasionally) and the entire ArcView window was visible. Again, when tasks were performed relatively slowly the student was able to see what the lecturer did. However, during the time that the lecturer had control, the student lost all control of his own desktop; unable to chat. So in order to continue the dialogue, the student had to continually retrieve control of the program to chat and then allow the lecturer to take control again. It is believed that this is a software bug that may be repaired in future versions, however alternatives such as voice communications by additional phone lines or mobile may be required in the short term. 129

8 Kate Sherren and Manolya Kavakli An Online Collaboration Model for the Distance Education Figure 1. Screenshot from a trial session between lecturer and student using ArcView and NetMeeting. If the problem continues, it is proposed that the pair in dialogue instead use the whiteboard function, which allows the user to paste images to a blank page, and for the other person to circle things, cross things out, draw boxes, and make other marks to indicate changes and improvements. The pasted images could be exported from ArcView maps, or could be screen snapshots. Both parties can use the whiteboard function and still maintain chat contact. However, both parties also have simultaneous control of the whiteboard, so the hierarchical control model may have to be used in order to maintain focus. The whiteboard and chat contents are both capable of being saved by either party, and then can be used as a record of the discussion for the lecturer, or study notes for the student. The student indicated satisfaction with the interaction supplied by the tutorial sessions, and found NetMeeting a very simple program to use. Undoubtedly, increased supply and uptake of alternative internet connection methods will make this type of interaction much more common. Conclusion Distance education students in creative or highly graphical fields need an environment in which they can increase their exposure to the work of other students, lecturer feedback and advice. The Internet offers an ideal environment for allowing more interaction to isolated students and improving upon the learning experience of traditional cartographic teaching methods. This paper has proposed methods for the inclusion of online collaboration into creative subjects by the use of NetMeeting, a common Microsoft teleconferencing software, and the format is planned to be operationally trialed at CSU in Autumn

9 An Online Collaboration Model for the Distance Education Kate Sherren and Manolya Kavakli Epilogue Based on feedback received on this paper at GeoCart 2003, the authors modified their plan for the teaching of SPA212 in Autumn The synchronous consultation mode described herein was abandoned after further testing, though the forum-based peer review process is being used. As this paper goes to press, this subject is still in progress, but early feedback indicates positive learning outcomes as a result of the exposure to additional designs and opinions in this asynchronous mode. Acknowledgements The authors would like to thank Jean Rivard for taking part in the pilot studies, and the peer reviewers for their contribution of suggestions for improving the manuscript. References Cagdas G, M Kavakli, A Ozsoy, N Esin Altas and H Tong, 2001, Virtual Design Studio VDS2000 as a virtual construction site: Game-like learning versus traditional design education, Proceedings of DCNET' 00: Design Computing on the Net'2000, January, Key Centre of Design Computing and Cognition, University of Sydney. Campbell DA, 1996, Design in Virtual environments Using Architectural Metaphor, A HIT Lab Gallery, Unpublished thesis, Master of Architecture, University of Washington, USA: (accessed December 17, 2002) Cartwright W, 2001, Proposal for a Collaborative Online Course in Multimedia Cartography, Proceedings of GeoCart 2001 National Cartography Conference, Taupo, New Zealand: New Zealand Cartographic Society. Cigognani A and ML Maher, 1997, Models of Collaboration for Designers in a Computer-Supported Environment, in: Maher ML, JS Gero and F Sudweeks (eds), Proceedings of Third International IFIP WG5.2, Workshop on Formal Aspects of Collaborative CAD, February 1997, Jenolan Caves, Australia, web site: (accessed December 7, 2002), Condon C, 1993, The Computer won t let me: Cooperation, Conflict and the Ownership of Information, in: S Easterbrook (ed), CSCW: Cooperation or Conflict?, London, Springer- Verlag, Dent B, 1999, Cartography: Thematic Map Design, 5 th Edition, WCB McGraw-Hill. Dykstra EA and RP Carasik, 1991, Structure and support in cooperative environments: the Amsterdam conversation environment, International Journal of Man Machine Studies, 34, Greenberg S and M Roseman, 1998, Using a Room Metaphor to Ease Transitions in Groupware, Research Report 98/611/02, Department of Computer Science, University of Calgary, Alberta, Canada. Ishii H and N Miyake, 1991, Towards an open shared workspace: computer and video fusion approach of TeamWorkStation, Communications of the ACM, 34 (12), Kalay YE and C Séquin, 1995, Designer-Client Relationships in Architectural and Software Design, Computing in Design, in: Kalisperis L and B Kolarevic (eds), Proceedings of ACADIA '95, Computing in Design: Enabling, Capturing and Sharing Ideas, October 1995, Seattle, USA. 131

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