Desktop productivity for business analysts and programmers

Using Responses and # of Responses to Back into Standard Deviation?

Reply
New Contributor
Posts: 2

Using Responses and # of Responses to Back into Standard Deviation?

Hope this is the right location! 

 

I have some data I'm trying to run t-tests on, but have to get creative with backing into the data to get the SD. I have the frequency distribution and N sizes, but not individual level data. What I've done so far (in excel, since I don't know how in SAS) is multiply the N size by the percent that answered each question either a 1,2,3,4,or 5 to determine what # of people in each group responses a certain way to each question (Sheet 1) and then transposed it to the format I *THINK* SAS will want it in (Sheet 2). It looks something like this

 

Question_AnswerResponseGroup_1Group_2Group_3
Q0A115020050
Q0A22100025
Q0A33252550
Q0A44752525
Q0A55502550
Q1A1105025
Q1A2210050100
Q1A33100750
Q1A44257525
Q1A55752550

 

From here I need to get the standard deviation of each question for each group and am at a total loss of how to do that. I'm not sure if I should keep the Question column parsed out the way it is (Question 1 Answer 1, Question 1 Answer 2) or just repeat Question1 for five rows and let the response column do the heavy lifting. 

 

Any help would be greatly appreciated! 

Super User
Posts: 24,004

Re: Using Responses and # of Responses to Back into Standard Deviation?

Is there a reason GROUP3 for Q0A1-5 doesn't add up to 300 like Group1/2? How should they add up here?

 

Standard deviation is usually used for continuous measurements, not categorical data. Can you explain a little more what you're looking to achieve here?

 


maldito wrote:

Hope this is the right location! 

 

I have some data I'm trying to run t-tests on, but have to get creative with backing into the data to get the SD. I have the frequency distribution and N sizes, but not individual level data. What I've done so far (in excel, since I don't know how in SAS) is multiply the N size by the percent that answered each question either a 1,2,3,4,or 5 to determine what # of people in each group responses a certain way to each question (Sheet 1) and then transposed it to the format I *THINK* SAS will want it in (Sheet 2). It looks something like this

 

Question_Answer Response Group_1 Group_2 Group_3
Q0A1 1 50 200 50
Q0A2 2 100 0 25
Q0A3 3 25 25 50
Q0A4 4 75 25 25
Q0A5 5 50 25 50
Q1A1 1 0 50 25
Q1A2 2 100 50 100
Q1A3 3 100 75 0
Q1A4 4 25 75 25
Q1A5 5 75 25 50

 

From here I need to get the standard deviation of each question for each group and am at a total loss of how to do that. I'm not sure if I should keep the Question column parsed out the way it is (Question 1 Answer 1, Question 1 Answer 2) or just repeat Question1 for five rows and let the response column do the heavy lifting. 

 

Any help would be greatly appreciated! 


 

New Contributor
Posts: 2

Re: Using Responses and # of Responses to Back into Standard Deviation?

[ Edited ]

Yes! 

 

Group 1 is 300 people, Group 2 is 275, Group 3 is 200. 

 

So what I essentially want to do is determine the difference between the responses to each of the questions and whether or not the difference is statistically significant. I hope to accomplish this by running the following independent t-tests

 

Group 1 vs Group 2 

Group 2 vs Group 3

Group 3 vs Group 1

 

For each of the questions.

 

Which, of course, requires the standard deviation to do. 

Super User
Posts: 24,004

Re: Using Responses and # of Responses to Back into Standard Deviation?


maldito wrote:

 

 

Which, of course, requires the standard deviation to do. 


 

I would have expected a Chi Square test since this is count/frequency data instead of t-tests using standard deviation.You can look at PROC FREQ for that. 

https://stats.idre.ucla.edu/other/mult-pkg/whatstat/

Ask a Question
Discussion stats
  • 3 replies
  • 132 views
  • 0 likes
  • 2 in conversation