The standard deviation is the square root of the variance returned by the VARP function.
Example
Suppose you administered five tests to your small class of five students. Using this population data, you could use the STDEVP function to determine which test had the widest dispersion of test scores. This might be useful in determining lesson plans, identifying potential problem questions, or for other analysis.
You enter the test scores into a blank table, with the scores for each student in columns A through E and the five students in rows 1 through 5. The table would appear as follows.
A
B
C
D
E
1
75
82
90
78
84
2
100
95
88
3
40
80
85
4
35
98
92
5
97
=STDEVP(A1:A5) returns approximately 20.3960780543711, the standard deviation of the results of Test 1.
=STDEVP(B1:B5) returns approximately 21.9453867589523, the standard deviation of the results of Test 2.
=STDEVP(C1:C5) returns approximately 8.49941174435031, the standard deviation of the results of Test 3.
=STDEVP(D1:D5) returns approximately 7.22218803410711, the standard deviation of the results of Test 4.
=STDEVP(E1:E5) returns approximately 2.99332590941915, the standard deviation of the results of Test 5.
Test 2 had the highest dispersion (standard deviation is a measure of dispersion), followed closely by Test 1. The other three tests had lower dispersion.
Example—Survey results
To see an example of this and several other statistical functions applied to the results of a survey, see the STDEVAVARPVARPA