A request. As we are nearing the completion of the first dissertation review in the blog, what else would you like me to address in future posts? Please send me an email with your ideas and questions! leann.stadtlander@waldenu.edu
You
have collected all of your quantitative data, entered it into SPSS (or
downloaded it), and double checked your data entry. Great… now what?? It can
feel intimidating to view your first real data set and know you need to figure
out what to do with it. I like to start with getting an overall feel for what
is going on by calculating means and frequencies. Let’s take a moment and
review what to use when.
If
your variable is continuous, meaning there are no categories that you set up
previous to the study you can calculate means and standard deviations. An
example of a continuous variable would be where you asked people to enter their
age today (e.g., 32, 56, etc.). Examples of categories would be gender: 1 =
female, 2 = male or age: 1 = 20-30, 2 = 30-40, etc.). Hopefully, these terms
are sounding familiar, if not go back to your stats book and review. A good
reference for SPSS is
Pallant,
J. (2010). SPSS survival guide, 4th ed.
Berkshire England: McGraw Hill
For
categorical variables (e.g., gender, education level) you can do a frequency
table and get a feel for how your data looks. Make sure you don’t have any data
entry errors- they will show up as a weird number, e.g., you have gender coded
as 1 & 2 and a 21 shows up in the frequency table. Go back to the original
data and double check it.
One
issue you may need to consider is what to do with missing data, for example
from people skipping questions. There are a number of ways to deal with this
issue. Check with your methodologist to see what they prefer. They will
probably ask you how many cells (individual data points) are missing, for which
variables are they missing, and what is the largest number missing per individual,
so be prepared for those questions.
Once
missing data issues are resolved, my usual next step is run correlations
between my variables just to get a feel for what is going on. I then do
scatterplots for any that show up as significant. Again, I am just trying to
get a feel for the data. My old undergrad stats professor used to say that you
need to “take a bath in your data.” I like that idea, you need to understand
the relationships before getting immersed in the formal data analysis.
You
should have developed an analysis plan in your proposal, so now is the time to
go to that. What happens if you just can’t figure things out? Contact your
committee members and ask for help. As a committee member I sometimes have
students send me their data set and I play with it a little, then I can talk
them through issues.
Sometimes
students decide to hire statistical consultants. Personally, I am not a fan of
this. I prefer that the student figure out the stats with the help of his or
her committee. The problem with a consultant is that you don’t really
understand what they did and why. Even if they explain it, you really don’t
have the level of understanding that you should. It misrepresents your
knowledge level. People reading your dissertation will assume that you did the
analyses and are capable of doing it (and perhaps teaching it!) again. If you
must use a stats consultant, my advice is to rerun all of the analyses that
they do, so you understand them too.
Another
aspect to consider is keeping track of all the analyses that you run and what
they show. There are several ways to do this. You can simply save all of your
SPSS outputs in a separate file on your computer (my least favorite, because
then you have to reopen each to see it). Another way is to print out all of
your data outputs and save them in a file or binder. My own favorite way to keep
my data output is to copy it or rewrite it as I go into a word file. The
advantage of this is that I am keeping everything together that is relevant
(you will generate a lot of irrelevant info as you go). Do keep in mind that
SPSS tables are not in APA format, so any that you want to use in your paper
will need to rewritten.
I
also find it helpful to think through what I am finding with each analysis
(even though this technically goes in c. 5, I find it helpful to think about it
at the analysis stage). Let’s work through an example, I find that my variable education
level is correlated with my dependent variable, emotional intelligence (EI) total
score. So my first question is which education level has a higher EI score? I
could do a scatterplot or could just calculate the means for each education
level (use analyze/ descriptive stats/explore). I then find that people with a
graduate degree have a higher emotional intelligence score than people with a
high school diploma in the sample. Is that what previous research has found? What
if this is not the relationship other researchers have reported? I need to
consider why my sample may be different. I check what else is correlated with
education- perhaps I find that for this sample, gender is highly related to
emotional intelligence. Do another scatterplot between gender and education.
Whoa- all of the graduate level participants are female. Could that be the
cause of the education and emotional intelligence score correlation?
Remember
your methodologist can help with any issues you may have. There are also
statistical consultants available for tricky issues, a faculty member can ask
questions on your behalf. Next time, we will look at qualitative analyses.
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