So I ran in this problem: I have to test whether Empirical Rule is applicable. Proportions I got is 73%, 94,7% and 99.1% (within one, two and three standard deviations). I'm worried about 73%. This is quite far away from 68% (that the empirical rule states). I have more than 1500 observations. Can I still state that Empirical Rule works here? What are the acceptable deviations?
Thanks in advance.