stats::variance -- the
variance
Introductionstats::variance(data) returns the variance
of the data.
Call(s)stats::variance(x1, x2... <, Sample>)
stats::variance([x1, x2...] <, Sample>)
stats::variance(s <, c> <, Sample>)
Parametersx1, x2, ... |
- | the statistical data: arithmetical expressions. |
s |
- | a sample of domain type stats::sample. |
c |
- | an integer representing a column index of the sample
s. This column provides the data x1,
x2 etc. |
OptionsSample |
- | with this option the given data are regarded as a ``sample'', not a as a full population. |
Returnsan arithmetical expression.
Related
Functionsstats::a_quantil,
stats::geometric,
stats::harmonic,
stats::mean, stats::median, stats::modal, stats::quadratic, stats::stdev
Detailsc is optional, if the data are given
by a stats::sample
object containing only one non-string column. Cf. example 3.
Example
1We calculate the variance of three values:
>> stats::variance(2, 3, 5)
14/9
Alternatively, the data may be passed as a list:
>> stats::variance([2, 3, 5])
14/9
Example
2We create a sample:
>> stats::sample([[a1, b1, c1], [a2, b2, c2]])
a1 b1 c1
a2 b2 c2
The variance of the second column is:
>> expand(stats::variance(%, 2))
2 2
b1 b1 b2 b2
--- - ----- + ---
4 2 4
Example
3We create a sample consisting of one string column and one non-string column:
>> stats::sample([["1996", 1242], ["1997", 1353], ["1998", 1142]])
"1996" 1242
"1997" 1353
"1998" 1142
We compute the variance of the second column. In this case this column does not have to be specified, since it is the only non-string column:
>> float(stats::variance(%))
7426.888889
We repeat the computation with the option Sample:
>> float(stats::variance(%2, Sample))
11140.33333
stats::sample.