View Single Post
  #3   Report Post  
JE McGimpsey
 
Posts: n/a
Default feel that the STANDARD DEVIATION formula on Excel is incorrect !!

1.82574.... is the sample standard deviation for the data set which is
returned by

=STDEV(5,6,8,9)

1.58113... is the population standard deviation for the data set, which
is returned by

=STDEVP(5,6,8,9)

The formulas that XL uses to calculate both STDEV and STDEVP are already
in XL Help.


In article ,
"Ganapati Hegde" <Ganapati wrote:

Hi Microsoft Office,

The formula for Standard Deviation provided in Excel ( =STDEV(range) )gives
a different answer when compared with the answer got by manually calculating
the Standard Deviation formula provided in the Statistics text books.

E.g.: Numbers - 5, 6, 8 & 9. When calculated using Microsoft Excel =STDEV
(....) we get an answer 1.82574185835055

But when calculated using the Text book methods of calculating of the Std.
Dev. formula, we get 1.58113883008419

Please can you advise why there is a difference in the answers?

Please can you make appropriate changes in the future Microsoft Office
releases giving the breakup of the formulas used? May be in the HELP option.
Because there are millions of excel users who are completely dependent
(unaware) on the formule in excel.

Many thanks,

Ganapati Hegde
Mumbai, INDIA.
+91 98195 58330


----------------
This post is a suggestion for Microsoft, and Microsoft responds to the
suggestions with the most votes. To vote for this suggestion, click the "I
Agree" button in the message pane. If you do not see the button, follow this
link to open the suggestion in the Microsoft Web-based Newsreader and then
click "I Agree" in the message pane.

http://www.microsoft.com/office/comm...=0c737fb5-0d7b
-4400-b5ba-bacddb8541d9&dg=microsoft.public.excel.worksheet.f unctions