Quote:
Originally Posted by Bobblehead
The sample size you need will also affect your variance.
In this case, with this sample size you will have a 95% confidence level that the result is within +-5 (actually 5.34).
A sample size of 1000 gives you +-3 "19 times out of 20".
Handy calculator for this: http://www.surveysystem.com/sscalc.htm |
Exactly, so you also get a tighter sample.