Lecture Podcasting, September 2006
Paul Kates, Mathematics Faculty LT3 Liaison
Lecture Podcasting
In 2004 the University of Western Australia (UWA) conducted a case study on student and faculty use of their lecture recording system Lectopia (formerly iLecture). The system has been in use since late 1998, recording every subject areas mentioned below. In 2004, 7000 individual lectures were recorded. In 2005, 9500 lectures. This comprehensive university has about 12K undergrads and 4K graduates and includes science, engineering, medicine, law, humanities, social science, economics among its studies. In 2004, over 5K students used the recorded lectures with an average of 40 hits per recording.
The main findings of the case study of Lectopia, the University of Western Australia's (UWA) audio and video lecture recording and distribution system are found in several papers and pages at their home page. The 2004 study included 1262 completed student surveys, system usage logs and lecturer feedback. Here is a summary of some of their findings taken from this site:
Student surveys have shown that students using Lectopia fall into the following categories:
- students revising, including exam preparation
- students catching up on the occasional missed lecture
- part-time students or students with difficulty attending face-to-face lecture (including students with disabilities)
- students seeking clarification of lecture material (including students with English as a second language)
- students studying in regional locations
- students choosing to access Lectopia rather than attend face-to-face lecture
The uptake in the use of Lectopia by teaching staff at UWA has been significant. Apart from the benefits to students, teaching staff have reported many other benefits from using Lectopia:
- students are less likely to ask repetitive questions about material covered in lectures
- informal feedback can be gathered from students using the Lecture Rating feature
- accessing one's own lectures provides the opportunity for self-review
- listening to previous year's lectures can be useful when preparing lectures
The following two sections are taken from page 6 of Williams, J., Fardon, M., "On-demand internet-transmitted lecture recordings: attempting to enhance and support the lecture experience", presented at ALT-C, September 2005. This is a very good paper, reporting on research about lecturing, lecture recording and student learning styles, in addition to the 2004 iLecture case study.
Who used the recorded iLecture lectures?
- Students in the 16-20 and the 26-30 age categories are most likely to use iLectures
- Mature-age students (30+) are more likely to prefer to attend face-to-face lectures
- Part-time students prefer to attend face-to-face lectures
- Students with greater traveling distance to university are more likely to use iLectures
- Female students are more likely to use iLectures
- Students using iLectures are most likely to be average students academically, i.e. credit level (60-69%)
- High distinction students (80-100%) and students who fail (0-49%) are most likely to never use iLectures
- Students in first year level units are more likely to use iLectures than second and third year level students
Reasons given by students for using iLecture
- Students who prefer iLectures: 25% of students indicated they prefer to use iLectures rather than attending the face-to-face lecture. 42% of this group of students indicated that they either "always" or "regularly" attend the face-to-face lectures.
- Students with timetable clashes: 38% of students indicated they use iLectures due to a timetable clash.
- Work commitments: 30% of students indicated they use iLectures due to work commitments. The more hours that students worked, the more likely they were to use iLectures.
- Family commitments: 9% of students indicated they use iLectures due to family commitments. Further to this, 81% of students with children indicated they either "always" or "regularly" use iLectures, with only 54% of students with children indicating they either "always" or "regularly" also attend the face-to-face lecture.
- Revision: 60% of students indicated they use iLectures for revision purposes, with 75% of these students indicating that they either "always" or "regularly" attend the live lecture.
- Review occasional missed concepts: 43% of students indicated they use iLectures to review occasional missed concepts covered in the face-to-face lecture, often to complete note-taking or to review complex arguments.
- Convenience: A number of students reported using iLectures as it is inconvenient to attend the face-to-face lectures. Numerous issues were raised by students, including the traveling time/distance to the campus, parking difficulties, and having only one lecture scheduled on a particular day.
- Other reasons reported by students: Medical conditions or illnesses, and sports commitments.
Will lecture attendance decline from use of recorded lectures?
Here are Williams and Fardon's conclusion from page 7 of the above paper:
One of the most common questions that we are asked when discussing iLecture is whether students continue to come to lectures. When analyzing the use of eClass (a system with similarities to iLecture), Brotherton and Abowd (2004) reported that eClass did not encourage students to skip class. While no formal analysis of lecture attendance was undertaken as part of this study, many lecturers have reported that there are some students who are not attending lectures, and that the number of students attending lectures reduces as the semester progresses. This feedback from lecturers should be understood in the context of the results from the student survey that found that only 25% of students using iLecture prefer using this format to attending the face-to-face lecture. And of that group of students, 42% indicated that they still attend the face-to-face lectures either "regularly" or "always". This clearly indicates that while iLecture does have an impact on lecture attendance, it is likely that there are other more significant factors that are impacting whether students attend lectures. In particular, the demands on students in other areas such as work and family commitments, as it evidenced from the number of students using iLecture for these reasons. This finding also suggests that there are factors (perhaps social) other than gaining access to lecture material that encourages students to attend the face-to-face lectures.
Another smaller study at UCDavis done in the fall of 2005 with 4 courses showed findings consistent with the above UWA study. Here is one comment from the study:
80% of the students surveyed indicated that having mp3 lectures available enhanced the course value. Nearly all of the students commented how they appreciated having the mp3 files for review or study. The participating faculty also said they were approached by many students who appreciated having the lecture digitally accessible and that it was a benefit to the class.
Lecture recording and podcasting in Canada and the US
There is interest in lecture podcasting at several Canadian universities (Carleton, Brock, Toronto and UBC) according to a February 2006 National Post story about Apple's iTunes U program coming to Canada. Like Apple's regular iTunes music service, iTunes U is a hosting service for audio files. But instead of popular music, the contents are audio recordings of course lectures, guest lectures, commencement and other special events at participating universities. The free service offers each university its own large file space (100's of GB) and controlled access to individual content items. There is also the choice of using the iTunes U site for storing the content description files (podcast XML files, similar to RSS files), while keeping the audio content files (e.g. MP3 files) on local university servers, to address privacy concerns and obligations.
To listen to lectures, students use Apple's iTunes software (or other podcast software, Juice for example) to subscribe to folders of audio, video or PDF files. Instructors provide a URL to students for use in their podcast application to locate the folders. When instructors add new files to folders, they are automatically downloaded by the student's podcast application. Students can listen through their computers or transfer the audio files onto portable MP3 players.
Berkeley, Stanford and Duke are using iTunes U. Some universities have set up their own podcasting systems. The West Lafayette campus of Purdue has 60 summer courses this year using podcasts in many subjects (1 math course and 1 statistics course). Berkeley also has a separate webcast service that has hosted 110 courses from the fall of 2004 to the summer of 2006. The summer 2006 courses, 38 in number, are mostly science, engineering and computer science courses.
I found the following four sites about how to record a lecture on a PC (Mac, Windows or Linux) and create a podcast XML file very useful:
- picture of the podcast process
- wikipedia article on podcasting
- how to record a podcast using free software audacity and easypodcast
- how to make a podcast on a Mac with garageband
MP3 file settings for speech recording are not as sensitive as for music recording. The following four audacity recording settings produced acceptable listening and showed no decline in quality.
File size | Number resolution | Sampling rate | MP3 quality level |
---|---|---|---|
28 MB | 32 b | 44 kHz | 64 bps |
14 MB | 32 b | 44 kHz | 32 bps |
10.5 MB | 32 b | 44 kHz | 24 bps |
7 MB | 32 b | 44 kHz | 16 bps |
A growing number of classrooms in the Math and Computer (MC) building have an audio output wire from the audio amplifier housed in the computer podium. This wire is tagged with the word "Recording". It is used in combination with the wireless microphone found inside the podium. To record a lecture, plug the wire into the "Line-in" port (blue with -> into arrow) on your laptop; start the audacity program and click the round circle record button; turn on and attach the wireless mic to your shirt; after the lecture, click the square stop button; save your recording file. Back at your office, load the file and trim the blank space from the beginning and end of the recording using the mouse to select the blank areas of the graph (or click where the lecture really begins and use "delete from start"). Under the File menu, select "Preferences" and "File Formats" and choose 16 as the MP3 bit rate (see table above). Under the File menu, select "Export As MP3". Click on the MP3 file created to review the sound quality.
Several things can go wrong. The wireless mic batteries can die - there are spares in the podium. Without a working mic, nothing is recorded. Your computer can run out of disk space - audacity uses about 700 MB per recording hour. Later, a compressed version of this file is made into a much smaller MP3 file. But, the original high-quality recording is still on your disk. The microphone picks up your voice very well, but questions from the class are very faint, sometimes inaudible - repeat student questions before answering.
If you decide to try podcasting in your class, I'd like to help set up a learning case study of your class. Please get in touch with me.
Liaison Information
Please contact me if you would like further information. Paul Kates, Mathematics Faculty LT3 Liaison, pkates@uwaterloo.ca, x37047
This page is located at www.math.uwaterloo.ca/~pkates/LT3/podcasting.html