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PearsonChiSquareTest
BUILT-IN MATHEMATICA SYMBOL
PearsonChiSquareTest
PearsonChiSquareTest[data]
tests whether data is normally distributed using the Pearson
test.
PearsonChiSquareTest[data, dist]
tests whether data is distributed according to dist using the Pearson
test.
PearsonChiSquareTest[data, dist, "property"]
returns the value of
.
Details and OptionsDetails and Options
- PearsonChiSquareTest performs the Pearson
goodness-of-fit test with null hypothesis
that data was drawn from a population with distribution dist, and alternative hypothesis
that it was not. - By default, a probability value or
-value is returned. - A small
-value suggests that it is unlikely that the data came from dist. - The dist can be any symbolic distribution with numeric and symbolic parameters or a dataset.
- The data can be univariate
or multivariate
. - The Pearson
test effectively compares a histogram of data to a theoretical histogram based on dist. The bins are chosen to have equal probability in dist. » - For univariate data the test statistic is given by
, where
and
are the observed and expected counts for the 
histogram bin, respectively. - For multivariate tests, the sum of the univariate marginal
-values is used and is assumed to follow a UniformSumDistribution under
. - PearsonChiSquareTest[data, dist, "HypothesisTestData"] returns a HypothesisTestData object htd that can be used to extract additional test results and properties using the form htd["property"].
- PearsonChiSquareTest[data, dist, "property"] can be used to directly give the value of
. - Properties related to the reporting of test results include:
-
"DegreesOfFreedom" the degrees of freedom used in a test "PValue"
-value"PValueTable" formatted version of 
"ShortTestConclusion" a short description of the conclusion of a test "TestConclusion" a description of the conclusion of a test "TestData" test statistic and
-value"TestDataTable" formatted version of 
"TestStatistic" test statistic "TestStatisticTable" formatted 
- The following properties are independent of which test is being performed.
- Properties related to the data distribution include:
-
"FittedDistribution" fitted distribution of data "FittedDistributionParameters" distribution parameters of data - The following options can be given:
-
Method Automatic the method to use for computing
-valuesSignificanceLevel 0.05 cutoff for diagnostics and reporting - For a test for goodness of fit, a cutoff
is chosen such that
is rejected only if
. The value of
used for the
and
properties is controlled by the SignificanceLevel option. By default,
is set to
. - With the setting Method->"MonteCarlo",
datasets of the same length as the input
are generated under
using the fitted distribution. The EmpiricalDistribution from PearsonChiSquareTest[si, dist, "TestStatistic"] is then used to estimate the
-value.
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