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Instructions
for Stage 8 of the Semester Paper |
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Recoding the Responses and Obtaining Revised Frequencies
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For this stage you must convert the responses/answers provided by the survey respondents
into a form suitable for use in the 2 x 2 tables we will use for the semester paper.
Because the table will hold only 2 responses for each variable, questions containing
more than two possible responses must be collapsed/combined.
For example, the original responses to the question, "do you agree or disagree that
abortion should be legalized in the US?" might be 1) strongly-agree, 2) agree,
3) don't know, 4) disagree and 4) strongly-disagree. For this
class, we will combine categories so that 2 and only 2 categories are used in the
final table. For example: 1) agree and 2) disagree. In general, the
best thing to do with responses such as, don't-know, neutral, and
uncertain is to simply eliminate individuals who answered in that manner
from the analysis. For the most part, I have already done this for you - these responses
already should have been converted to "system-missing" and SPSS should automatically
eliminate them from analysis.
So, for this stage, combine the survey respondents' answers into 2 categories in
some logical manner. For interval variables such as age, you might consider combining
all categories below the mean or median into "young" and those at or above the mean
or median into "old." You are not limited to this decision. Your hypothesis might
deal with the differences between teenagers and adults. In that case, your "teenage"
category should include those who are 18 and 19, while the "adults" should be everyone
else.
For political party (if you are using this variable), you will have to do something
about the "Independent" category as well as those who are "Undecided."
You will also have to do something to combine the "Strongly Republican" and
"Not so Strongly Republican" categories etc. The easiest thing to do in this
case is to call your categories "Republican" and "Everyone Else" or
similar. Here, you would place the "Strong Republican" and "Not so Strong
Republican" in the same category and all other responses into the category
"Everyone Else." You can make similar decisions with other variables
- use your own judgment and imagination. I will not deduct any points for any reasonable
decision on how you separate your categories. Just make a written note of how you
did this so that you can report these decisions when you write the methods section
in an upcoming stage.
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You must turn in SPSS Output that contains:
1. A frequency table for each of the 3 or 4 original variables that you will be
using in your paper. The table should contain the original variable name.
2. A frequency table for each of the 3 or 4 recoded variables after combining categories.
This table should contain the new variable name. The table should also not include
any responses that you will be eliminating from your analysis.
Follow the instruction below to accomplish these tasks using SPSS software. If you
are uncertain about how to open the data file, refer back to the instructions in
stage 3.
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Combining (Dichotomizing) Response Categories
- Decide how to divide the responses for each of your variables into two categories
(dichotomize).
- After you have made your decision about how to divide the responses into 2 (and
only 2) categories for each of the variables in all three of your hypotheses (the
IVs, the DVs, and the Control variables) you will have to "recode" the responses
and place the altered responses into another data-column (another variable). Remember
that all of the responses are stored as numbers - e.g., "male" is coded as "1" and
"female" is coded as "2."
- Before going further, you should examine the spss output from the first spss assignment
and write down the numerical coding for each of the response categories. You can
do this from the bottom of the Data Editor window by selecting the "Variables View"
tab. The window will change from a display of the GSS data to a display of details
about each variable.
- If you look under the column marked "Values" and click on the icon displaying three
dots (...) a window will open that will show you the codes corresponding to each
response category. Write these down for future reference.
- Next, from the Data Editor Window, go into the "Transform" menu and select "ReCode"
and then "Into Different Variables." Again, a window will appear with your variables
on the left. Let's start by recoding one variable at a time:
- Next, highlight one of your variables that requires recoding (dichotomizing). Hit
the arrow icon to place this variable into the text box in the middle of the window.
- On the far right side of the window, there is a text box that is labeled, "Output
Variable - Name." Type in any name that you will remember (caution - if you are
using a version of spss older than version 12, it will only accept names less than
8 characters long). It may be wise to use the original name and add the letter "R"
to the end to designate it as a "recoded" variable. For example, if the original
IV is "sex" you could call the new/recoded variable "sexR."
- If you wish, you can also include a descriptive "label" in the appropriate text
box that will provide addition information in your output (experiment with this
if you wish). Afterward hit the "CHANGE" icon.
- Hit the icon that says, "old and new values." With your notes about the coding for
the response categories from the step above at your side, type in the first old
(existing) value on the left text box and a new value in the right text box. Then
hit the "ADD" icon. Do this for each of the responses you wish to recode.
For example, if I were using the "FeFam" variable that measured belief in traditional
gender roles, I would see that the responses are listed from 0 to9. Responses 1
and 2 represent "strongly agree" and "agree" respectively. Because it makes sense
to combine these into a single "Agree" category, I would first place "1" in the
old value and a "0" in the new value and hit "ADD." I would then then place "2"
in the old value and "0" in the new value and again hit "ADD." The window on the
bottom will then indicate that any response marked as either 1 or 2 in my original
variable will be "recoded" so that the new response is marked "0." I would
do something similar for the old categories 3 and 4 - recoding them so that they
now equal "1."
- Responses like "don't know," "undecided," "not applicable," etc. should have already
been changed to "system-missing" so that they won't appear in our analysis.
- You can also experiment with the options to include a range of responses to recode
to a single new value - this is advantageous especially if you are using age as
one of your variables. Figure this out on your own and ask me if you run into problems
you can't solve. (Warning - this can be frustrating and confusing until you do this
once or twice - don't worry, be patient it will eventually make sense and seem easy
after a short time)
- After you have specified the old and new values for one variable hit the "OK" button.
In the "Data Editor" window a new column should appear with the new variable name
that you specified above. Check things over to see if everything appears correct.
It would be wise to go to the analyze menu and run "frequencies" on the recoded
variable, compare with the "frequencies" on the original variable and check to make
certain that your recodes are correct.
- Repeat the above procedures for each of your IVs, DVs, and control variables so
that they are all dichotomized. When you re-enter the window for each subsequent
variable you will have to hit "reset" to erase the old information before entering
the information for the next variable.
- Run the frequencies command on all of the original variables as well as all of the
recoded variables (refer to the instructions in prior stages). Look closely at the
output to determine whether your work is correct.
- Make certain to save a copy of your data set that has the recoded variables for
future use.
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Saving your Work
You should save your output in a file by going into the file menu (on the output
window) and selecting "save as." You should also save a copy of the dataset that
has your recoded variables by going into the file menu (on the Data Editor Window)
and selecting "save as." You can either over-write the existing dataset or create
a new one. If you have room on your computer/removable-disk, I would recommend the
latter. We will soon use these recoded variables during a subsequent stage.
Optional
The instructions above do not allow you to save the work you have done with the
exception of saving the final dataset and saving the output. If you make a recoding
mistake or other mistake, you likely will have to start over. SPSS, however, allows
you to save your work in the form of a "syntax file" (.sps file). In the steps above,
instead of hitting "OK" for the last step when asking for output, hit "PASTE" instead.
This will open a "syntax" window containing computer instructions representing the
recoding and analysis decisions you made above. Each time you hit "PASTE" new syntax/instructions
is added. You can then highlight the instructions you wish to repeat and run them
at a later time. You can also manually change these instructions. Like the output
and data windows, the syntax can be saved by going into the file menu and selecting
"save-as." Experiment with this if you wish. It may save you time in the future
and it would be a good learning experience, particularly if you are planning to
take a more advanced course in research methods or statistics. If you have questions
about this ask.
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