OK, I'll give you some supplemental information
about the Roomba Study that isn't available on other links that will help
you with your paper. I'll also tell you exactly what statistics to
run.
You were observing randomly selected mature Roombas (indeterminate
sex - they can't be sexed visually - males and females are comparably sized)
in their natural environment (a 4 x 6 ft black laboratory table). Each
observation on each tape may be a different Roomba, but you can't be sure,
because the selection is "random." Given that the herd of Roombas was
estimated to be 500-800, we can be fairly confident that the majority of
our observations were of separate individuals. The tapes were made over
a period of several weeks for each tape, see below. The Roomba environment
was marked off into quadrants and numbered using Liquid Paper, a substance
that other unpublished observations had shown to be undetectable to Roombas.
The Roombas were observed at the beginning of their "days" - they are diurnal
animals. In two of the tapes we provided supplemental feedings to the
Roombas either on the left or right side of their environment. From
previous unpublished observations, we determined that Roombas readily consumed
the 6.2 mm white paper disks we provided. These disks were produced
using a standard hole punch and Boise X-9 20 lb paper. The disks were
provided throughout the taping sessions to ensure a ready supply of this
high density food. In the third tape, there was no intervention, only
naturally occurring foods could be consumed.
The reader will want to know how many observations were made. The reader
will want to know about how many observer pairs there were. You need
to report interobserver reliability data. Toward that end, run
X2
tests on the two observer's ratings of Behavior and Quadrant. In each
case, since there are more than 2 levels of each variable, you should check
Contingency Coefficient. Interpret the resulting values as you have
been instructed to in the lecture portion of the course.
Ignoring the Tape variable, report the frequency with which each Behavior
occurs. Because the frequencies of many behaviors are relatively low,
we will collapse across behaviors and focus on whether the animal went straight
(Y/N). Of course, the other option that isn't straight is to turn in
some way. Now both observers may not agree on this new variable.
In your hypothesis tests, you were allowed to simply use either observer's
data. Here, we'll be more restrictive and create yet another variable
that is Straight (Y/N) only IF both observers agree on the behavior.
The reader will want to know how many observation have been dropped to get
to this point. It relates to reliability and the issue of whether you
have enough remaining data to tell a rational story.
Now, to look for evidence of satiety, we will do
X2s -
no surprise! First, we'll look for the frequency of being on the left
versus right (sort of) while collectively considering only the two tapes
with supplemental feedings. We'll create yet another variable that
isn't Right/Left, but will take those measures and convert them to Same/Opposite
side of the Roomba environment relative to where the supplemental food is.
Additionally, since the Roomba should start out hungry and change its behavior
after feeding, we will compare the 1st and 2nd halves of the observation
period to create a 2 level Time variable. So you will have a 2 X 2
X2 with the variables being Time and Side. To get
a clean look at the Same/Opposite concept, we'll do a straight
X2
on only that measure as well.
Finally, we'll do a
X2 on the Straight behavior while
again collapsing the data from the two "fed" tapes into one level of a two
level Fed (Y/N) variable. Obviously, the unfed tape will be the other
level of this variable. Again we want evidence of satiety, so we will
use the 1st and 2nd halves of the observation period for the Time variable.
So, we're going to end up looking at Fed X Straight twice - once in the 1st
half and once in the 2nd half. Obviously, if there is satiety in evidence
here, there should be a difference between halves in the relationship between
Fed and Straight.
The bad news is, that the results of this study aren't crystal clear, in
some ways. You have to report it like it is and do your best in the
Discussion to make sense of it.
Good luck!! (
Supplemental syntax)
.