6.7 KiB
Statistical Tests
The test module includes methods that enact popular statistical tests. The tests that are implemented are Z tests, T tests, and F tests. Also included are methods for developing confidence intervals. Currently regression is not included but it should be included soon (once matrix inversion is fixed).
Statistics Instance Functionality
zscore( value[, flag] )
Returns the z-score of value
taking the jStat object as the observed
values. flag===true
denotes use of sample standard deviation.
ztest( value, sides[, flag] )
Returns the p-value of value
taking the jStat object as the observed
values. sides
is an integer value 1 or 2 denoting a 1 or 2 sided z-test.
The test defaults to a 2 sided z-test if sides
is not specified. flag===true
denotes use of sample standard deviation.
tscore( value )
Returns the t-score of value
taking the jStat object as the observed
values.
ttest( value, sides )
Returns the p-value of value
taking the jStat object as the observed
values. sides
is an integer value 1 or 2 denoting a 1 or 2 sided t-test.
The test defaults to a 2 sided t-test if sides
is not specified.
anovafscore()
Returns the f-score of the ANOVA test on the arrays of the jStat object.
anovaftest()
Returns the p-value of an ANOVA test on the arrays of the jStat object.
Static Methods
Z Statistics
jStat.zscore( value, mean, sd )
Returns the z-score of value
given the mean
mean and the sd
standard deviation
of the test.
jStat.zscore( value, array[, flag] )
Returns the z-score of value
given the data from array
. flag===true
denotes
use of the sample standard deviation.
jStat.ztest( value, mean, sd, sides )
Returns the p-value of a the z-test of value
given the mean
mean and sd
standard
deviation of the test. sides
is an integer value 1 or 2 denoting a
one or two sided z-test. If sides
is not specified the test defaults
to a two sided z-test.
jStat.ztest( zscore, sides )
Returns the p-value of the zscore
z-score. sides
is an integer value 1 or 2
denoting a one or two sided z-test. If sides
is not specified the test
defaults to a two sided z-test
jStat.ztest( value, array, sides[, flag] )
Returns the p-value of value
given the data from array
. sides
is
an integer value 1 or 2 denoting a one or two sided z-test. If sides
is not specified the test defaults to a two sided z-test. flag===true
denotes the use of the sample standard deviation.
T Statistics
jStat.tscore( value, mean, sd, n )
Returns the t-score of value
given the mean
mean, sd
standard deviation,
and the sample size n
.
jStat.tscore( value, array )
Returns the t-score of value
given the data from array
.
jStat.ttest( value, mean, sd, n, sides )
Returns the p-value of value
given the mean
mean, sd
standard deviation,
and the sample size n
. sides
is an integer value 1 or 2 denoting
a one or two sided t-test. If sides
is not specified the test
defaults to a two sided t-test.
jStat.ttest( tscore, n, sides )
Returns the p-value of the tscore
t-score given the sample size n
. sides
is an integer value 1 or 2 denoting a one or two sided t-test.
If sides
is not specified the test defaults to a two sided t-test.
jStat.ttest( value, array, sides )
Returns the p-value of value
given the data in array
.
sides
is an integer value 1 or 2 denoting a one or two sided
t-test. If sides
is not specified the test defaults to a two
sided t-test.
F Statistics
jStat.anovafscore( array1, array2, ..., arrayn )
Returns the f-score of an ANOVA on the arrays.
jStat.anovafscore( [array1,array2, ...,arrayn] )
Returns the f-score of an ANOVA on the arrays.
jStat.anovaftest( array1, array2, ...., arrayn )
Returns the p-value of the f-statistic from the ANOVA test on the arrays.
jStat.ftest( fscore, df1, df2)
Returns the p-value for the fscore
f-score with a df1
numerator degrees
of freedom and a df2
denominator degrees of freedom.
Tukey's Range Test
jStat.qscore( mean1, mean2, n1, n2, sd )
Returns the q-score of a single pairwise comparison between arrays
of mean mean1
and mean2
, size n1
and n2
, and standard deviation (of
all vectors) sd
.
jStat.qscore( array1, array2, sd )
Same as above, but the means and sizes are calculated automatically from the arrays.
jStat.qtest( qscore, n, k )
Returns the p-value of the q-score given the total sample size n
and k
number of populations.
jStat.qtest( mean1, mean2, n1, n2, sd, n, k )
Returns the p-value of a single pairwise comparison between arrays
of mean mean1
and mean2
, size n1
and n2
, and standard deviation (of
all vectors) sd
, where the total sample size is n
and the number of
populations is k
.
jStat.qtest( array1, array2, sd, n, k )
Same as above, but the means and sizes are calculated automatically from the arrays.
jStat.tukeyhsd( arrays )
Performs the full Tukey's range test returning p-values for every
pairwise combination of the arrays in the format of
[[[index1, index2], pvalue], ...]
For example:
> jStat.tukeyhsd([[1, 2], [3, 4, 5], [6], [7, 8]])
[ [ [ 0, 1 ], 0.10745283896120883 ],
[ [ 0, 2 ], 0.04374051946838586 ],
[ [ 0, 3 ], 0.007850804224287633 ],
[ [ 1, 2 ], 0.32191548545694226 ],
[ [ 1, 3 ], 0.03802747415485819 ],
[ [ 2, 3 ], 0.5528665999257486 ] ]
Confidence Intervals
jStat.normalci( value, alpha, sd, n )
Returns a 1-alpha confidence interval for value
given
a normal distribution with a standard deviation sd
and a
sample size n
jStat.normalci( value, alpha, array )
Returns a 1-alpha confidence interval for value
given
a normal distribution in the data from array
.
jStat.tci( value, alpha, sd, n )
Returns a 1-alpha confidence interval for value
given
the standard deviation sd
and the sample size n
.
jStat.tci( value, alpha, array )
Returns a 1-alpha confidence interval for value
given
the data from array
.
jStat.fn.oneSidedDifferenceOfProportions( p1, n1, p2, n2 )
Returns the p-value for a 1-sided test for the difference
between two proportions. p1
is the sample proportion for
the first sample, whereas p2
is the sample proportion for
the second sample. Similiarly, n1
is the sample size of the
first sample and n2
is the sample size for the second sample.
jStat.fn.twoSidedDifferenceOfProportions( p1, n1, p2, n2 )
Returns the p-value for a 2-sided test for the difference
between two proportions. p1
is the sample proportion for
the first sample, whereas p2
is the sample proportion for
the second sample. Similiarly, n1
is the sample size of the
first sample and n2
is the sample size for the second sample.