Equivalent of std dev for discrete data-set
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Ken Feldman.
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February 19, 2010 at 3:39 pm #53302
I have a data-set of 10 discreet categories each one with 20 observations rated on a 5 point rating scale. I now want to analyze the variation within each category and compare them across the different categories. Had this been continuous data, I would have calculated the std dev of each and also graphically depicted the variation across categories with a box plot. What approach should I follow as my data is for 1-5 ratings and not continuous ?
0February 19, 2010 at 5:48 pm #189549In a past life I analyzed survey response statistics, and basically treated the data as continuous. Purists may disagree, especially since you’re on a scale of 1-5. I had scales of 1-7 and 1-10 to deal with, which made it a bit easier.
0February 20, 2010 at 3:13 am #189557
TierradentroParticipant@johnInclude @john in your post and this person will
be notified via email.You are dealing with a 5 point Likert scale and a sample size of 20. How does getting a statistically shaky measure of dispersoin help you get answers to your critical questions? I don’t think your findings will be actionable. And if not actionable, what is the point?
0February 20, 2010 at 3:24 am #189558
TierradentroParticipant@johnInclude @john in your post and this person will
be notified via email.But I didnt answer your question. Perhaps this article will prove helpful:
https://www.isixsigma.com/library/content/c040809a.asp?action=print0February 20, 2010 at 5:00 pm #189564
Ken FeldmanParticipant@DarthInclude @Darth in your post and this person will
be notified via email.Usually you just report out the percentage or proportion of the 1-5 scale. If it makes sense you can report out as “top two box (1 & 2)” and “not top two box”. Not real comfortable with treating as continuous. You are aware that you can calculate s.d. for discrete distributions such as Poisson and Binomial?
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