Activity #2

In the following, Michael Kane advocates the use of magic routines to help students to learn that what they think they are seeing is not always correct. He uses astrology in one of his demonstrations to teach students about the "Barnum Effect" (also known as the "Forer Effect"). He also mentions one activity and one example that will demonstrate to students the fallibility of memory The activity makes use of word lists from the Deese-Roediger-McDermott memory studies. The example is the Challenger-explosion study:
Neisser, U., & Harsch, N. (1992). Phantom flashbulbs: False recollections of hearing the news about Challenger. In E. Winograd & U. Neisser (Eds.), Affect and accuracy in recall: Studies of "flashbulb memories. New York: Cambridge University Press.

Wed, 3 May 2000
Michael Kane
University of North Carolina at Greenville
mjkane@uncg.edu

I think...magic routines...can be quite effective.... I know a few simple tricks myself, mostly picked up from Penn & Teller books, and students seem to find them pretty compelling. The astrology demo I recently discussed on TIPS may also be an effective way to get students to experience a certainty-uncertainty shift. [In personal correspondence sent to me, Michael next discusses this demonstration.]

The horoscope demonstration is made up of bits and pieces of other "Barnum Effect" demos as well as some Kabalarian personality descriptions I got from the web. My "act" is borrowed from descriptions in the literature, as well as from James Randi's "Secrets of the Psychics" NOVA video.

Here's how I use it in my "Psych of 'Weird' Beliefs" course. I ask all the students in the class to write down the date and places of their birth (and, if possible, the exact time). I tell them that I'll be giving them to an astrologer who has offered to work up some brief horoscopes (personality descriptions, really) for them for free, as long as I will give him/her some publicity. A few classes later, I give every student a copy of the [following] horoscope, but I obviously change the name, birthdate and birthplace on each:

"John Doe, your given name, in addition to the star' and planets' positions on your birth date of 8/22/67, in Big City, GA, present you as an outgoing, optimistic and responsive person. In short, you are cordial, warmhearted, and friendly. Thus, you have a great need for other people to like you and admire you. However, you also have a tendency to be critical of yourself.

"You have a clever mind, a sense of responsibility, and an appreciation for the finer things in life. You can be serious-minded and not inclined to make light of things even in little ways, and in your younger years you had more mature interests than others your age. You pride yourself on being an independent thinker and do not accept others' statements without satisfactory proof--you like to check things out for yourself, and if the subject is interesting enough you explore it further. You prefer your own ideas rather than others'. You have had the desire to accomplish something outstanding and to do something very worthwhile for humanity, especially early in your life. Thus, you sometimes exhibit a tendency to let your imagination run away with you into flights of fancy. Some of your aspirations tend to be pretty unrealistic.

"You have a great deal of unused capacity that you have not used to your advantage. However, when you start a project you intend to finish it and stay with it to completion--a strong drive to keep moving toward a goal.

"Home and family mean a great deal to you and it is natural that you should desire the security of a peaceful, settled home environment where you can enjoy the companionship of family and friends. Whatever you set out to accomplish you do your very best to complete in accordance with what you consider to be right. In the home you assume your responsibilities capably, having the self-confidence to form your own opinions and make your own decisions. Others can rely on you; once you have given your word you will do your utmost to fulfill a responsibility. However, there is a tendency to be a little too independent in your thinking, sometimes, and so it may be difficult for you to accept the help of others when you should.

"While you have some personality weaknesses, you are generally able to compensate for them. Your sexual adjustment presented some problems for you when you were younger. Independent, disciplined and self-controlled outside, you tend to be worrisome and insecure inside. At times you have serious doubts as to whether you have made the right decision or done the right thing.

"You prefer a certain amount of change and variety and become dissatisfied when hemmed in by restrictions and limitations. You are a person who sees opportunities or plans decisive steps with an aptitude for initiating ideas and actions and proceeds with caution, yet you sometimes vacillate when coming to a final decision.

"At times you are extroverted, affable and sociable, while at other times you are introverted, wary and reserved. You are often unduly conscious of yourself when being observed, and you can be shy in unfamiliar situations. You have found it unwise to be too frank in revealing yourself to others. Security is a major goal of yours."

It works well to hand each student their own in an envelope with their name printed up on a mailing label. I then ask everyone to open up their own, and read it silently. I mention that these are personal, so for now they should not share the contents with anyone. After all have finished, I ask them to write down a number on their sheet, indicating on a 1-5 scale how well the astrologer was able to capture their personality. I then ask for a show of hands of all those who wrote down a 4 or 5. A substantial proportion of the class usually raises their hands. I then tell them that, before they get too excited about this astrologer's capabilities, they should listen to the horoscope that I received. As I read mine out loud, which is exactly the same as all of theirs, the group gradually begins to catch on and looks of astonishment and laughter begin to spread. I then discuss the relevant research on the Barnum effect (it goes by other names as well). At the end of the course, many students spontaneously mention this demo as particularly memorable and effective in demonstrating that you don't have to be a fool to fall for schemes like this. Interested readers may consult, for example:

French, C. C., Fowler, M., McCarthy, K., & Peers, D. (1991). Belief in astrology: A test of the Barnum effect. Skeptical Inquirer, 15, no. 2 (Winter), 166-172.

I think that "false memory" demonstrations (a la the Deese/Roediger & McDermott list memory procedure) are also effective in getting students to question the validity of their memories. In this context, students are impressed by the Neisser study of "Challenger" flashbulb memories, where VERY few subjects were accurate in their memories for the event, despite great confidence in their accuracy. When I teach a unit on reconstructive processes in memory, I think the point about uncertainty gets through loud and clear. Students seem a lot more willing to question the veridicality of their own memories after learning about the relevant experimental work.