# What is the minimum samples required for Customer Survey?

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#### Sixsigmalearner

Hi,

I am working on a BPO project where in they receive surveys on customer satisfaction. The survey scale is (0-10) and 9-10 been considered as CSAT. However, they consider avarage of all the surveys are the performance measure. (ASAT). In a month they do approx 10,000 transactions and they receive 100 surveys. The current performance is 7.5. Management feels that less number of surveys is impacting the performance and if the survey count is increased, there is a chance of improving the scores.

I want to know what is the best of asking the client to increase the survey sample.

#### Steve Prevette

##### Deming Disciple
Super Moderator
Re: Minimum Samples Required

You can run into a lot of problems with treating numerical responses on a survey as a "measurement" - that is a 4 is twice 2, 8 is twice 4, which is what you are doing when you average the quantities.

Better to deal with - what percent are a 9 or 10, or consider this method ->

http://www.efcog.org/wg/esh_es/Statistical_Process_Control/docs/Survey_Analysis.pdf

Bottom line - you may not need more samples, but better analysis.

S

#### Sixsigmalearner

Re: What is the minimum samples required for Customer Survey ?

Thanks for the quick reply. I want to understand what is the right approach to calculate the sample size in this case. I cannot change the approach of the calculation rather can convince management that we do not require more samples.

I

#### isoalchemist

Re: What is the minimum samples required for Customer Survey ?

IMHO: I'd ask the question why is the response what it is? Is the survey too simple that it is ignored or too complex that it is a waste of time. Is it getting to the right people or is it just a drop in the box?

Even if you can calculate a correct sample size how do you get to that level becomes the problem. I also agree with Steve that you need to look behind the numbers a bit more. Simple averages work great for batting averages or winning percentages, but are limiting in developing true information.

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