From: amead@s.psych.uiuc.edu (Alan Mead)
Subject: two classroom exercises
Organization: UIUC Department of Psychology
Date: Wed, 2 Sep 1992 21:43:07 GMT

I cannot say I scrutinize this group so I must apologize now if shareing
what have been useful classroom demonstrations is either innappropriate or
unoriginal.  I would like to hear about your class-room examples too.

I use these to teach t-tests because they usually result in a large 
group difference and are (for my students) intuitively interesting.

The first demonstrates different risk-taking behaviors for persons faced with
a gain rather than a loss.  Ss are presented with these choices (either in
a counter-balanced within-subjects design or else independant groups respond 
to one version each).

Gain Version:

  Imagine that you have this choice of dates:

    A)  100% chance of one night with your favorite celebrity
        (eg., Mel Gibson/Cindy Crawford)

    B)  50% chance of no date
               or
        50% chance of two nights with your favorite celebrity

  Would you choose A or B? _____


Loss Version:

  Imagine that you have this choice of dates:

    A)  100% chance of one night with your worse nightmare (eg., Saddam 
        Hussein/"Mama" from the movie "Throw Mama from a Train")

    B)  50% chance of no date
               or
        50% chance of two nights with your worst nightmare

  Would you choose A or B? _____


As predicted by Prospect Theory (among others), Ss typically choose the sure
gain (A in the Gain Version) and avoid the sure loss (choose B in the Loss
version).

In my class, we did 2 t-tests (gender and frame) and a gender x frame 
ANOVA.
VARIABLE  VALUE N      MEAN     STD DEV     T       DF     P
SEX         f   12     0.50     0.52 
            m   12     0.75     0.45       
                                            0.804   22    .42

FRAME       +   12     0.08     0.29
            -   12     0.75     0.45
                                           -4.3     22     .00

SOURCE          MSS           F          P
SEX             0.166         1.43       0.25
FRAME           2.667        22.86       0.00
SEX*FRAME       0.667         5.71       0.03


LEVEL        LEVEL     
SEX          FRAME     N        MEAN      SD
f            +         6        0         0
f            -         6        1.0       0
m            +         6        0.1667    0.408
m            -         6        0.5000    0.548

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The second demo I did I got from the net, but I don't think it was here.
Perhaps someone would like to take a shot at explaining the effect:

If you were standing on the surface of the moon holding a pen and you released
your grip on it what would the pen do?

A)  Float upward
B)  Float where you released it
C)  Float downward

The correct answer, I am certain, is C.  The pen would weight 1/6 of its
Earth weight, but would certainly not hover or go ballistic. 

Now the strange thing about this question is that women usually get it
wrong while men usually get it right (at least in the two informal samples
I've collected).  It seems to be another "hurl" question.  Here is the data
from my class (1=right, 0=wrong):
SEX   N      MEAN          SD
F     12     0.0833        0.2887
M     13     0.8462        0.3756

T(23)=-5.6577, p < .0000

(In the same sample, women scored higher on a simple math question).
Comments: Gated by NETNEWS@AUVM.AMERICAN.EDU