Friday, April 21, 2017

Quantitative Analyses, Part II

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 (see my previous discussion). Check with your committee 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 to 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 statistics professor used to say you need to “take a bath in your data.” I like that visual; you need to understand the relationships before being immersed in the formal data analysis.

You should have developed an analysis plan in your proposal, so now is the time to go to it. What happens if you just cannot 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 the student figure out the statistics with the help of his or her committee. The problem with a consultant is you may not really understand what they did and why. Even if they explain it, you really may not have the level of understanding you should. It misrepresents your knowledge level. People reading your dissertation will assume you did the analyses and are capable of doing it (and perhaps teaching it!) again. If you must use a statistics consultant, my advice is to rerun all of the analyses they do, so you understand them too.

Next time we will continue our consideration of the quantitative analyses. Do you have an issue or a question that you would like me to discuss in a future post? Would you like to be a guest writer? Send me your ideas! leann.stadtlander@waldenu.edu

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