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The standard distribution screen

On this screen - https://app.dataquest.io/m/309/z-scores/6/the-standard-distribution

Which means are these referring to?

In the last exercise, the mean values were both extremely close to 0. For instance, we got a mean of -1.1429992333726227e-16 (notice the e-16 at the end) for the z-scores distribution of the SalePrice column. This number uses scientific notation to abbreviate what in full would be -0.0000000000000001429992333726227 . Also, both the standard deviations were also very close to 1: 1.0000000000000002 and 0.9999999999999997 .

On the last screen -

I got these values - image

It’s the values corresponding to those same variables as you share in your post. Since the values are so small, they aren’t going to be exactly the same as what DQ got (that’s why they say we got a mean of) or what I got (which is different to yours and DQ).

This is likely related to - Floating point issues/limitations in Python, which I believe DQ has mentioned in some of the previous (at the beginning, I think) courses/modules.

So these discrepancies are to be expected here.

Thanks! It was helpful