Standard Deviation with 2 Variables

Roughly 8 minutes.

This a super useful program for anyone taking a statistics class. The only reason I have this listed under "Intermediate" is that I'd rather you have the understanding of these things before coming to this. On top of that, Stats is an intermediate course anyway. Onwards!

1. Create a new program and name it "STANDEV"

2. Press "stat" and go to the "CALC" tab

3. Select "LinReg(ax+b)" then press "2nd" "1" comma "2nd" "2". Start a new line

4. Hit "2nd" "stat" and select "ʟRESID"

5. Press "sto→" then "2nd" "3". Start a new line

6. Press "2nd" "3", then "x²"

7. Press "sto→", then "2nd" "4". Start a new line

8. Press "2nd" "stat", go to the "OPS" tab, and select "dim("

9. Press "2nd" "3" ")", then press "sto→" "alpha" "log". Start a new line

10. Type "√((", then press "2nd" "stat", then go to the "MATH" tab and select "sum("

11. Type "L₄))/(N-2))→S", then start a new line

12. Press "prgm", go to the "I/O" tab and select "Disp"

13. Press "alpha" "ln"

14. It should look like:

:LinReg(ax+b) L₁,L₂

:ʟRESID→L₃

:L₃²→L₄

:dim(L₃)→N

:√((sum(L₄))/(N-2))→S

:Disp S

So that is that program. Like if this was helpful, drop a comment if you have questions or need help. Thanks for reading!

-Nate