# Thread: Calculating the confidence interval of a survey when "sample space > 2"

1. ## Calculating the confidence interval of a survey when "sample space > 2"

Hello.

I have conducted a survey in which the surveyed could answer: {yes, no, maybe}

Here´s the issue: I want to calculate the confidence interval for each of these three proportions (respective answers to number of people surveyed) and while I know how to do it for two proportions, I do not know how to do it for three.

2. This is a good question. I have never encountered it myself either.

If you have a sample and want to know the true proportion of participants voting "yes" and your estimator or sample proportion is 'p' then '1-p' will represent those voting "no" and "maybe".

Likewise

If you have a sample and want to know the true proportion of participants voting "no" and your estimator or sample proportion is 'p' then '1-p' will represent those voting "yes" and "maybe".

and finally,

If you have a sample and want to know the true proportion of participants voting "maybe" and your estimator or sample proportion is 'p' then '1-p' will represent those voting "no" and "yes".

That's my thinking, happy for others to correct me.