Standard deviations between stocks and for expected values

archived_user

New member
Joined
Jun 18, 2026
Messages
0
Reaction score
0
Hi -
Is there a way to calculate the standard deviation between 2 stocks on the BAII Plus?
Also, is the standard deviation for the expected value Sx or sigma x when using 2nd Data?
Thanks
 
Hi San-br,
yes you can.
2nd + 7 will get you to the Data Worksheet.
Input the data points for the Xs and Ys.
2nd + 8 will bring you to the Stat Worksheet.
Scroll down and you will see
n = number of data points.
Xbar = Mean of X
Sx = Sample Std Dev of X
Sigmax = population Std Dev of X.
This repeats for the Ys
There are more figures if you continue to scroll but the best one to know is r, this is the correlation coefficient.
Hope this helps.
 
san-br wrote: Is there a way to calculate the standard deviation between 2 stocks on the BAII Plus?
What, exactly, do you mean by “the standard deviation between two stocks”?
 
S2000magician wrote:
san-br wrote: Is there a way to calculate the standard deviation between 2 stocks on the BAII Plus?
What, exactly, do you mean by “the standard deviation between two stocks”?
S2000: eg Assume two stocks are perfectly negatively correlated. Stock A has a standard deviation of 10.2% and stock B has a standard deviation of 13.9%. What is the standard deviation of the portfolio if 75% is invested in A and 25% in B? ie of the portfolio
 
Degree_of_leverage wrote:
Hi San-br,
yes you can.
2nd + 7 will get you to the Data Worksheet.
Input the data points for the Xs and Ys.
2nd + 8 will bring you to the Stat Worksheet.
Scroll down and you will see
n = number of data points.
Xbar = Mean of X
Sx = Sample Std Dev of X
Sigmax = population Std Dev of X.
This repeats for the Ys
There are more figures if you continue to scroll but the best one to know is r, this is the correlation coefficient.
Hope this helps.
Pardon, meant portfolio, eg Assume two stocks are perfectly negatively correlated. Stock A has a standard deviation of 10.2% and stock B has a standard deviation of 13.9%. What is the standard deviation of the portfolio if 75% is invested in A and 25% in B?
Any shortcut for that with the calculator?
 
san-br wrote:
Hi -
Is there a way to calculate the standard deviation between 2 stocks on the BAII Plus?
Also, is the standard deviation for the expected value Sx or sigma x when using 2nd Data?
Thanks
What do you mean by the bold? The expected value is a constant (like mu), which has zero variance (and naturally, standard deviation is zero).
 
[ (0.2)(0.20 - 0.145)^2 + (0.5)(0.15 - 0.145)^2 + (0.3)(0.1-0.145)^2]^0.5 is the answer - any way to use the BAII to calculate this quickly?
 
Above answer is 0.035
it can be done by
2nd Data
X01=0.2, Y01=2, X02=0.15, Y03=5, X03=0.10, Y03=3
2nd Stat
and get sigma x = 0.035
 
Back
Top