So given this data from your sample, what do you get as your sample mean?

They're going to sample your data and suck you dry!

But there's a reasonable chance that your sample mean Your sample is always going to be within your data sample, right?

The difference between that data point, The difference between that data point and our sample mean.

They're saying that there are n data points in this sample.

It's always going to be the center of your data sample.

What you do is you take the difference between each of the data points in the sample minus the sample mean.

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And that's equal to the sum of all the data points in the sample.

But it's completely possible that the population mean is outside of your data sample.

So, the numerator is going to be the sum of each of my data points in my sample minus my sample mean.

So for every data point in our sample, so we have n of them we take that data point, from it we subtract our sample mean square it and then divide by the number of data points that we have.

Sample mean is equal to Once again, you take each of the data points now in the sample, not in the whole population.

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Master Hindley! Master Hindley!

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little data, old data, no data.

Sample

And that's going to be taking every data point in the sample so going up to lower case n adding them up the sum of all the data points in our sample then dividing by the number of data points that we actually had.

So it says the lowest data point in this sample is an 8 year old tree

OK Master Haku, Master Haku!

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