March 23, 2008
There is a large body of research testing the hypothesis that, all else equal, people learn more through "active" than through "passive" learning.
Active learning is a loose concept. The version that I find most convincing, and I think the research best supports, is that learners who are cognitively active acquire and retain complex material better. (An early view pushed "behaviorally" active, but the evidence does not support this as well.)
Cognitive psychology supports many of the intuitive ideas behind active learning. For example, information is encoded more effectively into long-term memory -- and thus is more retrievable -- through elaboration and deep processing, more so than through repetition and massed practice. John Sweller at the University of New South Wales is perhaps the originator of "cognitive load" theory, and has done many studies indicating that simultaneously presenting an audience with the same material both orally and written -- precisely what we do when we lecture from text-dense bullet point slides -- reduces comprehension. Our brains experience conflict and overloading from the two separate, simultaneous presentations of nearly identical but slightly different words. One glaring example we all know: simultaneously displaying multiple points on a slide almost guarantees that most of the audience WILL NOT LISTEN to the speaker during the time they spend reading the content on the slide.
McKeachie's book (see image) is one of my favorite books of teaching advice that emphasizes active learning methods (and much else).
My use of slides in teaching
Over the past two years I have drastically changed the way that I use slides while teaching. (Some students still see some "old style" slides because I haven't finished replacing all of my teaching materials -- it takes a lot of work!) I have noticed that in course evaluation comments many students appreciate my presentation style, but some criticize it. One of the criticisms I've seen a few times is that my slides are not very helpful *after* class.
I think, from the comments, that the students want me to provide them with a lecture outline that they can use as a set of pre-written notes to study. That sounds nice, and might be a good idea sometimes, though I worry that providing everything (the readings, the lecture, the lecture notes, the sample problems and sample exams with solutions) pre-written is not good for learning: where is the *active* learning that research has shown to be essential? In any case, I don't feel an obligation to provide lecture outlines and notes that I have written (though some student comments suggest that they think they are entitled to this).
The obligation I do feel is to teach effectively, so that students learn successfully. And I have been convinced that the very standard approach to classroom slideware is ineffective. The standard approach, of course, is to provide a detailed set of bullet points: essentially, a lecture outline with notes. Many faculty more-or-less use the slides as their script, if not quite reading from them nonetheless going through each bullet as displayed. Gosh, as students sometimes say on a related topic: "I read the reading assignment in the textbook -- why just repeat it in class?"
The problem is deeper. First, putting a detailed outline and notes on the screen, and then talking through them creates a cognitive overload that decreases learning. Second, it promotes passive learning, which is less effective than active learning.
In my new presentation style I have worked hard (and believe me, it takes a lot longer to develop one of my new presentations than to prepare a standard bullet point outline presentation: I basically have to do the former first, to figure out what I want to say, then start from scratch to prepare the accompanying illustrations) to support learning by using multimedia material to complement the spoken words. I present material to illuminate, provide associative material, or provoke.
Some concepts are better understood (at least by some learners) visually, so I illuminate with a graph or a figure or an animation. Other times, I provide material -- often with cultural references (though I perhaps overdo this, since many of my students are foreign and may miss some of the cultural references) -- that I hope will trigger associative links, prompting students to more active processing and elaboration of the material. Yet other times I try to provoke them (with humor -- often self-deprecating since that's usually less likely to offend *others* -- sarcasm, surprising mental leaps or associations), again to get them to think differently and more deeply (or simply to wake up :).
I use a mixture of visual and auditory material. The visual includes photographs, words (but rarely more than one sentence per slide, and often just one word or phrase to EMPHASIZE a point, not repeat verbatim what I'm saying), paintings, graphs and figures, etc. I occasionally include a video clip, but I've not developed good skills at finding video illustrations appropriate to my lectures. Pity: dynamic visuals usually attract attention better than static. I do make use of color, contrast, size and other variations to increase the impact of my visuals. For auditory material I often use clips of popular music (sometimes classical or jazz), but have also created a few auditory demos.
These presentations do not make for good outline/lecture note handouts! I agree with the students on that. But I think they make the lectures themselves much more effective. I also provide the students with readings, sometimes supplemented with pre-lecture "reading guides". I put some lecture notes in the "presenter notes" section of my slide files, and then publish collapsed versions of the slides with the notes to provide partial lecture outlines.
Yes, I could do even more class preparation than I already do, creating in addition a lecture outline / notes document to handout (or post after class). But I don't want to do that instead of my more kinetic, dramatic, and complementary visual presentations. I think the loss in cognitively active learning in the lecture would be a much greater loss. So, I put the priority on trying to give effective lectures, rather than bad lectures accompanied by slide outlines to review after class.
And finally, I really do believe that students learn better if they take some lecture notes, take notes on the readings, and then after class, use those (and the slides, such as they are, and the audio or video recordings of lecture that I usually make available for my large lecture classes) to make one's own annotated outline. The activities of reviewing, distilling, organizing and summarizing are precisely the sort of learning activities we know are most effective.
I don't mean to claim that I have any special genius at lecturing in large classes, or that my way is necessarily best. I think (and my course evaluation scores over the years support this) that I am a better than average classroom teacher, but that there is substantial room for improvement. That's why I keep reading the research on teaching, and keep working to improve my pedagogical methods over time. I've put a lot of hours into analyzing, critiquing, and ultimately completely changing my visual presentation aids the past two years, and I'll keep putting time into improving my lecture skills.
March 08, 2008
Some plagiarism resources
There are many resources available concerning plagiarism, how to catch it, what to do about it, etc. Here are several:
- Assessment in Higher Education: Plagiarism
- American Historical Association: Standards of Professional Conduct
- JISC Internet Plagiarism Advisory Service
- The OWL (Online Writing Lab) at Purdue: Avoiding plagiarism
It has been my casual impression, as a teacher, that graduate students are plagiarizing more frequently than they use to (I haven't taught undergrads since the earlier 90s, so I have no opinion about them). This view is widely held, I sense, though I don't know if there is much careful evidence to support it. Certainly there is a sense that plagiarism is easier, now that there is so much text available on the Internet and cut-and-paste is so easy; the economist in me thinks that if the costs have gone down and the expected penalties are not much higher then the amount of plagiarism will increase.
(It is not immediately obvious that expected penalties have increased: it is also somewhat easier to catch Internet-based plagiarism, since search tools facilitate finding matching phrases. But as a teacher I think that the ease of catching has not increased as much as the ease of plagiarizing.)
In confronting students in the past few years, I also have the casual sense that there is less understanding of why plagiarism is unacceptable in academia. A typical response is "I did the research, I found the information, why should I have to rewrite it in my own words?"
Jack Shafer has published a column in Slate.com magazine entitled "Eight Reasons Plagiarism Sucks". He focuses on plagiarizing in journalism, but his concerns for the most part translate to academia as well, and are worth reading by scholars. Most people seem to understand that plagiarism is a type of theft (but doubt that original authors lose much or care much if they aren't cited in an unpublished term paper). But Shafer emphasizes harm to original authors is but one, and perhaps the least concern. His other concerns include "Journalism is about truth, not lies", "It corrupts the craft", "It promotes the dishonest".
When I try to educate straying students, I, too, emphasize the importance of trust between author and reader. I point out that if a boss finds that an employee is cutting corners and plagiarizing, even if the ideas presented are good, the boss will stop trusting the employee, and that is the beginning of the end.
There is another concern for students: You don't learn as much when you plagiarize. Learning is much more than learning to find what others have written on a topic. Even if you do nothing more than rewrite the ideas in your own words, cognitive psychologists have convincingly shown that the deeper processing and rehearsal that this entails greatly improves the writer's learning of the material. (Which is not to say that rewriting someone else's ideas is enough to avoid plagiarism: you need to provide attribution for the ideas, as well.) And there is also the not small matter of learning how to write in the first place!
March 02, 2008
LaTeX for new scholars
In my primary research fields (economics and computer science) most scholars use LaTeX for text processing, as in many other fields. It's a fabulous tool for those who write scholarly text, especially if the work involves formulas, tables or figures.
It is not a WYSIWYG word processor, but a markup language backed by the world's best automatic typesetting system (the underlying program, TeX, was written by the god of algorithms, Donald Knuth). On most platforms, however, there are integrator programs that do a nice job of providing an editor, a compiler and a previewer, which on today's fast machines means that you can see the result of what you're doing almost instantly. The advantages over word processors (like Word) is that the system is built soundly on scientific principles of typesetting so its default output is gorgeous, and it is infinitely configurable and extensible. (I produce essentially all of my papers in LaTeX; go download one of my recent papers to see an example of how it looks.) And the community of professionals who have written packages and extensions for it is huge and dedicated. The learning curve is a bit steep, though the defaults are so fine that to get up and started on basic term papers, etc., does not take long, especially for anyone with the skills and intelligence of a Ph.D. student.
There are a huge number of guides for starting to learn LaTeX. I still find that my first reference is often the original (though revised) by Leslie Lamport. A widely regarded online guide for learners is Nicola Talbot's LaTeX for Complete Novices. One you get the basics, the two go-to guides I most often consult are by Mittelbach et al., and The Not So Short Guide to LaTeX 2&epsilon by Oetiker et al.
Nicola Talbot has written (still in process but current draft is available online) a new guide, specifically for Ph.D. students: Using LaTeX to Write a Ph.D. Thesis.