What is an Empirical Distribution and How to Calculate its Variance?

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Homework Statement


I'm given data for 5 years of number of accidents. The problem asks about the Variance of the empirical distribution of the number of accidents per year.


Homework Equations





The Attempt at a Solution


I'm not sure what an empirical distribution means. I wasn't able to find a good example or definition online. At first I went and just found the average (total accidents / 5) and then used that to find the 2nd central moment, or the variance. I'm not sure if that is the correct way to do it. The part that confuses me is the empirical distribution part of it. If someone could clarify if I'm on the right track or what an empirical distribution is, that'd be great. Thanks for any help.
 
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newbiewannabe said:

Homework Statement


I'm given data for 5 years of number of accidents. The problem asks about the Variance of the empirical distribution of the number of accidents per year.


Homework Equations





The Attempt at a Solution


I'm not sure what an empirical distribution means. I wasn't able to find a good example or definition online. At first I went and just found the average (total accidents / 5) and then used that to find the 2nd central moment, or the variance. I'm not sure if that is the correct way to do it. The part that confuses me is the empirical distribution part of it. If someone could clarify if I'm on the right track or what an empirical distribution is, that'd be great. Thanks for any help.

It is just asking for the variance of the data sample.
 
So is the way I did it at first correct?
 
newbiewannabe said:
So is the way I did it at first correct?

I don't know, since you did not show your work. However, if your calculations are correct, and the problem statement was exactly as you said it was, then the answer will be OK, too.
 
Okay sounds good. I think I got it figured out. Thanks for your help.
 
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