How can I know if my sample is representative?

iocana

Hi all

I am getting into the sampling topic. When we get a sample by using any of the available tools, we need to know if the sample we have created is representative or not for audit purposes.

I have done some research but I cannot find any solution for checking this. Is there any solution available that could tell me if my sample is representative?

I also found a Chi Square test but it does not seem correct to me as, for example, when I select 1% of my data, the result is that the hypothesis is true, therefore my sample is representative....and this seems wrong to me 

Many thanks in advanced!

mbarone

The random sample tool should do it.  If someone says "how do you know it's representative"?  Then pick a couple metrics to focus on, and check the distribution between the population set and the random sample set.  They should be pretty close.  That's what I've done anyway - it's basically just proving that the random sample tool is truly random.