Apple iWork '09 User Manual
Page 299
Chapter 10
Statistical Functions
299
Usage Notes
The VAR function finds the sample (unbiased) variance by dividing the sum of the
Â
squares of the deviations of the data points by one less than the number of values.
It is appropriate to use VAR when the specified values represent only a sample of a
Â
larger population. If the values you are analyzing represent the entire collection or
population, use the VARP function.
If you want to include text or Boolean values in the computation, use the VARA function.
Â
The square root of the variance returned by the VAR function is returned by the
Â
STDEV function.
Examples
Assume you have administered five tests to a group of students. You have arbitrarily selected five
students to represent the total population of students (note that this is an example only; this would
not likely be statistically valid). Using the sample data, you could use the VAR function to determine
which test had the widest dispersion of test scores.
The results of the VAR functions are approximately 520.00, 602.00, 90.30, 65.20, and 11.20. So test 2
had the highest dispersion, followed closely by test 1. The other three tests had low dispersion.
Test 1
Test 2
Test 3
Test 4
Test 5
Student 1
75
82
90
78
84
Student 2
100
90
95
88
90
Student 3
40
80
78
90
85
Student 4
80
35
95
98
92
Student 5
75
82
90
78
84
=VAR(B2:B6)
=VAR(C2:C6)
=VAR(D2:D6)
=VAR(E2:E6)
=VAR(F2:F6)
Related Topics
For related functions and additional information, see:
“Survey Results Example” on page 362