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← Udacians Facebook Friends - Mean - Intro to Descriptive Statistics


Showing Revision 3 created 05/25/2016 by Udacity Robot.

  1. >> So, here's the data and you see that people entered this data on January 2nd,
  2. and that the data goes all the way down to cell B28, right here, and it starts
  3. at cell B2. Now, we can calculate the average anywhere in this white space. So,
  4. let's pick this one, looks like a good cell, good old cell D4. So, we'll write
  5. equals average of cell B2 all the way to B28. Now, we'll just make sure that all
  6. of the data is highlighted with this dotted green line. That way, we know that
  7. we are accounting for all of these data. And then we push Enter. So, you should
  8. have gotten that the average Udacian, at least in this sample, has 585 Facebook
  9. friends. Another way to do that is to sum cells B2 to B28 and then divide by how
  10. many people there are. So, there are 27 people and we get the same thing because
  11. remember, what we just did here when we took the sum of all the data values then
  12. divided by n, that's the formula for the mean, for any dataset. And that's what
  13. you worked with earlier in this lesson. So, spreadsheets are not only useful,
  14. but they're a great way to look at the same concepts in a different way.