BUILT-IN MATHEMATICA SYMBOL
PairedZTest
PairedZTest[data]
tests whether the mean of the data is zero.
PairedZTest[{data1, data2}]
tests whether the means of
and
are equal.
PairedZTest[dspec,
]
tests for zero or equal means assuming a population variance
.
- PairedZTest performs a hypothesis test on data with null hypothesis
that the true population mean is some value
, and alternative hypothesis
that
.
- Given
and
, PairedZTest performs a test on the paired differences of the two datasets.
- By default a probability value or
-value is returned.
- A small
-value suggests that it is unlikely that
is true.
- The data in dspec can be univariate
or multivariate
.
- The argument
can be any positive real number or a positive definite matrix with dimension equal to the dimension of data.
- The argument
can be a real number or a real vector with length equal to the dimension of the data.
- PairedZTest assumes that the data is normally distributed and that the variance is known and not estimated from the data.
- If variances or covariance matrices are not provided, PairedZTest treats the sample estimate as the known variance or covariance.
- PairedZTest[dspec,
,
0, "HypothesisTestData"] returns a HypothesisTestData object htd that can be used to extract additional test results and properties using the form htd["property"].
- PairedZTest[dspec,
,
0, "property"] can be used to directly give the value of
.
- Properties related to the reporting of test results include:
-
| "DegreesOfFreedom" | the degrees of freedom of a test |
| "PValue" | list of -values |
| "PValueTable" | formatted table of -values |
| "TestData" | list of pairs of test statistics and -values |
| "TestDataTable" | formatted table of -values and test statistics |
| "TestStatistic" | list of test statistics |
| "TestStatisticTable" | formatted table of test statistics |
- If a known variance
is not provided, PairedZTest performs a
-test assuming the sample variance is the known variance for univariate data and Hotelling's
test assuming the sample covariance is the known covariance for multivariate data.
- Options include:
-
- For tests of location, a cutoff
is chosen such that
is rejected if and only if
. The value of
used for the
and
properties is controlled by the SignificanceLevel option. This value
is also used in diagnostic tests of assumptions including tests for normality, equal variance and symmetry. By default
is set to
.
- Named settings for VerifyTestAssumptions in PairedZTest include:
-
| "Normality" | verify that all data is normally distributed |
Test whether the mean of a population is zero:
| Out[2]= |  |
The full test table:
| Out[3]= |  |
Test whether the means of two dependent populations differ:
The mean of the differences:
| Out[2]= |  |
| Out[3]= |  |
At the
level mean of the differenced data is not significantly different from 0:
| Out[4]= |  |
Compare the locations of dependent multivariate populations:
The mean of the differences:
| Out[2]= |  |
| Out[3]= |  |
At the
level the mean of the differenced data is not significantly different from 0:
| Out[4]= |  |
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