Lecture Webcasting at the University of Texas at Austin

Transcription

1 Lecture Webcasting at the University of Texas at Austin Coco Kishi Senior Systems Analyst, Division of Instructional Innovation and Assessment The University of Texas at Austin Tomoko Traphagan Research Associate, Division of Instructional Innovation and Assessment The University of Texas at Austin Comparison of Webcasting Systems Interest in lecture Webcasting is growing, as is the number and types of commercial turnkey tools that are available to produce rich media presentations for live and on-demand viewing. These tools or systems a hardware appliance in combination with server software facilitate the capture and synchronization of the video/audio of the lecturer along with presentation materials, as well as the compression and encoding of the media in various formats. By themselves these systems cannot provide complete automation of lecture recording, however. Still required is purchase and operation of cameras, audio mixers, file storage systems, and servers and their integration into the existing infrastructure with varying degrees of system scheduling and management. Primary considerations when selecting a Webcasting system are the type of visual content that will be streamed still images (PowerPoint) vs. time-based (videos) desired visual quality (resolution), bandwidth requirements, level of desired automation in scheduling and managing Webcasts, user interface, and ease of integration with existing infrastructure. Additional considerations include providing for automatic archiving, type of server and output format, preferred OS of audience, plug-in requirements to view webcasts, and availability of technical staff to develop desired additional components. Current costs for such systems are in the range of $9-12K for a basic encoding appliance (one unit per classroom), with up to an additional $20K needed for servers and licenses, management software, and maintenance support. Table 1 shows a comparison of key features of three systems in use at UT Austin, which are similar in that they all offer both mobile and static (rank mount) encoder units, handle multiple inputs (audio/video, VGA-digital output from any device such as laptop, document camera, projector), and provide live streaming viewable on PC or Mac using all major browsers. The College of Communication uses VBrick s VB Cast (encoder) and EtherneTV (media control system and scheduler), which can be automated and scaled to manage multiple video signals and output multiple open standard (MPEG4) streams. This system was selected because of the time-based instructional content (video) most often shown by faculty in the small to medium sized classes in the college. The flexibility of this system allows it to be easily integrated into existing infrastructure; however, it does not come with as many built-in features as do the other systems, and it is not ideal for streaming visually complex still-image content. The College of Natural Sciences has installed Envivio s Mindshare Composer (encoder) with 4Sight server, integrating it with a custom-built event scheduler, storage area network, and a virtual cameraman to automate lecture recordings in some of the largest classrooms on campus. This system was selected because it manages multiple video signals and outputs a single, multilayered, interactive, high-quality, open standard (MPEG4) stream. Its intuitive interface displays both time-based (video) and still-image (PowerPoint) content at very high resolution, and hence requires relatively high-bandwidth. It also requires a proprietary plug-in for viewing, but that has not been a problem for users. The Division of Instructional Innovation and Assessment (DIIA) and the College of Engineering use Sonic Foundry s MediaSite (encoder and server software) to stream still-image intensive content (PowerPoint) from medium- to large-enrollment lecture courses. This system was selected 1

2 because it offers many useful built-in features, it is easy to operate, and it can deliver high-resolution stillimage content at lower bandwidths. However, it is limited to Windows Media player and requires Windows Media Server to operate, and it is not ideal for streaming time-based instructional content. Table 1. Comparison of Systems Used at UT Austin Sonic Foundry VBrick Envivio Products MediaSite ML440 with server software VB Cast with EtherneTV Mindshare Composer with 4Sight streaming server software Server Windows Media Server Any Any Output as implemented Output Bandwidth Player requirements Windows Media, video capture at 180 x 240 and 15 fps, VGA capture using highresolution (1024 x 768) JPG snapshots up to 5 fps. Direct to MP3 and CD/DVD avail. 35 to 300 kbps (typically set at 150 kbps), defaults to 35 kbps on Macintosh Windows Media Player MPEG-4, both video and VGA at 320 x 240 and 30 fps. Averaging 600 kbps (not recommended for dial-up) QuickTime, Real Player, or Windows Media Player Video quality Low on Macs, good on PCs Good, dependent on player and platform User Interface Customizable interface No interface provided, templates come with system. created a simple 2- User controlled slide or video window synchronized window enlargement. viewer. Polling and ing function included Playback speed control Provisions for Captioning Content search features Automatic archiving for on-demand viewing Event management Automatic viewer tracking Available using PC only, as feature of Windows Media Can integrate live captioning only in newest version Slide thumbnails automatically generated. Video controls (fast forward, rewind) (Chapter indexes and text search are available in new version) Yes, disk storage comes with system Web-based access to scheduler comes with system Not in version implemented. (New version comes with viewer tracking) Using Windows Media on PC only, other than video controls (fast forward, rewind) No storage for archiving provided. Developed SAN integration Web-based access to scheduler comes with EtherneTV MPEG-4, video capture at 640 x 480 up to 30 fps. VGA capture in high-resolution (up to 1024 x 768) averaging 5 fps. Direct to MP3 and CD/DVD available Averaging 1000 kbps (cannot be watched with dial-up) Requires proprietary plug-in to view in QuickTime, Real Player, Windows Media Player, ActiveX Generally very good, dependent on player and platform Customizable interface templates come with system. User controlled independent placement, transparency and enlargement of video/slide windows. Using Windows Media on PC only Chapter indexing available but was not implemented for class webcasting. Video controls (fast forward, rewind) Yes, disk storage comes with system, however developed local SAN integration instead. Created it separately and integrated it with system IP address tracking possible 2

3 The systems in use at UT Austin have been successfully integrated into their areas of operation because technical staff have been able to develop additional functionality and efficiency. Because lecture webcasting at UT Austin is still an emerging technology with relatively limited and localized offerings, many issues such as bandwidth, player flexibility and the need for full automation, management and integration have not yet reached an enterprise level of consideration, but the dialog is beginning. Student Survey and Summary of Results At UT Austin, Webcasting has been offered as a study tool, not as a substitute for attending class. To understand the impact of webcasting on students in medium- to large-enrollment courses, s were conducted in select classes that were Webcast using the MediaSite or Envivio systems in 2005 and Table 2 summarizes results. Table 2. Survey Results Webcasting Course/Section System GEO 303 Introduction to Geology GEO 302D MediaSite Age of Dinosaurs GEO 302P Living with a Planet PGE 383 MediaSite Advanced Production Engineering (graduate course) CH 301 Principles of Chemistry I Envivio CH 302 Principles of Chemistry II 1 CH 310N Organic Chemistry II Survey Format paper Dates Enrollment 11/28/05-12/2/05 12/8/05-1/16/06 4/24/06-5/26/06 4/24/06-5/26/06 Response Rate % (136) % (20) % (43) 37 49% (18) % (122) In view of low response rates for the s, caution is necessary in interpreting the results. The nature of questions and student response patterns did not reflect differences in the webcasting systems, so the results should be interpreted as reflecting the impact of Webcasting in general, rather than of specific Webcasting systems. Results from a previous year s Webcasting study at UT Austin are also included when relevant. Attendance: One primary faculty concern is that Webcasting will decrease class attendance. While a majority of students in all classes (57-83%) reported that they preferred receiving course content in class rather than in other ways, many students (52-72%) skipped lectures at least once because of Webcasts. In fact, in a quasi-experimental study in the same geology course (GEO303), a statistically significant decrease in attendance was found for the Webcast section as compared to the non-webcast section. But, the frequency of class skipping because of Webcasts may be generally low. In chemistry and engineering, a majority of students (63-66%) reported that they never used Webcasts instead of attending class, or did so only rarely (31% in geology). Also, it was found that attendance could be effectively increased using certain teaching strategies, such as clearly communicating instructors expectations of attendance, employing in-class activities, and having pop-quizzes. Learning: In a quasi-experimental study in a geology course (GEO303), no statistically significant difference in test/quiz scores was found between Webcast and non-webcast sections, even though the attendance rate was lower in the Webcast section. In a previous study concerning a UT Austin 1 There were two Webcast courses of CH302 Principles of Chemistry II taught by two different instructors. 3

4 government course, students who more frequently watched webcasts performed better on the final exam (fall 2005). Student interviewees suggested that webcasts helped them improve their performance, while instructors perceptions of the effects of webcasts on performance were mixed. Comparing the webcasts with being in class: Geology students tended to agree more frequently (48%) than did students in other classes (19%) that Webcasts can replace being in class, that Webcasts are as good as going to class (57% vs %), and that Webcasts helped them learn course material better than being in class (36% vs %). More engineering and chemistry students (53-63%) stated that they would not take a course that is entirely Webcast (39% in geology). But half (50-51%) of the geology and chemistry students agreed or strongly agreed that they would enroll in two courses offered at the same time if at least one were being Webcast (40% in engineering). Course satisfaction: A majority of students reported that Webcasts were important to their overall course satisfaction, geology and engineering students in particular (59-63% agree/strongly agree, 42% in chemistry). Students considered Webcasts to be relatively more effective than office hours for helping them succeed in class in all colleges. In geology, students tended to consider Webcasts to be more effective than face-to-face lectures, which was not the case in the other disciplines. Other course resources (e.g., PowerPoint slides, lecture notes) were considered more effective than Webcasts in geology and engineering, but not in chemistry. Reason for watching Webcasts: Students cited learning and psychological benefits in watching Webcasts: (a) to make up for a missed class (50-82%), (b) to study and review course content (32-70%), (c) to understand lecture content better (42-67%), (d) to reduce anxiety about the course (37-69%), and (e) to control how they learned (57-87%). Most students watched at least one Webcast, averaging 7 (chemistry) to (geology and engineering) views during the semester. They typically watched the entire Webcast, most intensively before exams or during the same week as the lecture, during evening and night, and from home using high-speed Internet connections. Quality and difficulties: Most students (63-91%) in all colleges were satisfied with the overall quality of Webcasts. Geology students reported experiencing difficulties less frequently (9%) than did chemistry (17%) and engineering (37%) students. In geology, problems with sound volume (31%) and sound quality (22%) were reported most frequently. In chemistry, slow loading (47%) and slide and movie synchronization problems (25%) were reported most frequently. In engineering, slow loading (44%), slide and movie synchronization problems (39%), and video quality problems (39%) were reported most frequently. Students in all colleges typically did not seek any help when they had technical difficulties. Important features: In all classes, students considered important was seeing the blackboard or slides (90-100%), having play/stop/pause/fast forward/rewind (87-100%), scanning through the video (83-100%), having an index or search function (73-81%), and manipulating windows (70-80%). While these results suggest that webcasting offers learning and psychological benefits to students, the findings are as yet inconclusive, so it is critical to continue investigating the effects of webcasting and informing our future practices in integrating Webcasting into UT Austin courses. References Brittain, S., Glowacki, P., Ittersum J. V., & Johnson, L. (2006). Podcasting lectures: Formative evaluation strategies helped identify a solution to a learning dilemma. Educase Quarterly, (3), Harley, D., Henke, J., Lawrence, S., McMartin, F., Maher, M., Gawlik, M., & Muller, P. (2003, March 1). Costs, culture, and complexity: An analysis of technology enhancements in a large lecture course at UC Berkeley. Retrieved April 25, 2007, from University of California, Center for Studies in Higher Education Web site: 4

5 Traphagan, T. (2005). Class lecture Webcasting, Fall 2004 and Spring 2005: A case study. Retrieved April 26, 2007, from the University of Texas at Austin, Division of Instructional Innovation and Assessment Web site: (for the appendices: Traphagan, T. (2006a). Class lecture Webcasting, Fall 2005: A case study. Retrieved April 26, 2007, from the University of Texas at Austin, Division of Instructional Innovation and Assessment Web site: Traphagan, T. (2006b). Class lecture Webcasting, Fall 2004, Spring 2005, and Fall 2005: Summary of three case studies. Retrieved April 26, 2007, from the University of Texas at Austin, Division of Instructional Innovation and Assessment Web site: Biographical Sketches Tomoko Watanabe Traphagan is a research associate in the Division of Instructional Innovation and Assessment at the University of Texas at Austin. She has been involved in research and evaluation of various instructional technology programs at the university, including webcasting, Second Life, digital media services, course management systems, Web-based inquiry-based learning, and usability of instructional websites. Her research interests concern the impact of technology on students learning behaviors and performance. Address: The University of Texas at Austin Division of Instructional Innovation and Assessment Continuing and Innovative Education P.O. Box Wichita Street Austin, TX [email protected] URL: Phone: Fax: Coco Kishi is manager of the New Media Group at the Division of Instructional Innovation and Assessment at the University of Texas at Austin. She coordinates research and development for campus instructional technology projects and services in new media technologies in everything from streaming media to 3D visualization. Address: The University of Texas at Austin Division of Instructional Innovation and Assessment Continuing and Innovative Education P.O. Box 7817 Austin, TX [email protected] URL: Phone: Fax: