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StatsTtestResult

Namespace: STSLIB  ·  Library: Statistics Library

#include <sts/sts_ttest.h>

struct STSLIB::StatsTtestResult

Result structure for t-tests.

Per-call output of a Student t-test: t-statistics, p-values and degrees of freedom.

src/examples/ex_sts_statistics/main.cpp
const StatsTtestResult oneSample = StatsTtest::oneSample(a);        // H0: column mean = 0
const StatsTtestResult paired = StatsTtest::paired(a, b);           // H0: mean(a - b) = 0
const StatsTtestResult independent = StatsTtest::independent(a, b); // pooled variance, df = 10
const StatsTtestResult rightTail = StatsTtest::oneSample(a, 0.0, StatsTailType::Right);

Example​

Used in examples​

ex_sts_statistics​

Statistics library on small literal data sets with known answers.

src/examples/ex_sts_statistics/main.cpp, line 94
const StatsTtestResult oneSample = StatsTtest::oneSample(a);        // H0: column mean = 0
const StatsTtestResult paired = StatsTtest::paired(a, b);           // H0: mean(a - b) = 0
const StatsTtestResult independent = StatsTtest::independent(a, b); // pooled variance, df = 10
const StatsTtestResult rightTail = StatsTtest::oneSample(a, 0.0, StatsTailType::Right);
// scipy.stats.ttest_1samp / ttest_rel / ttest_ind
ok &= expectRow(oneSample.matTstat, {10.285912696499036, 0.24544034683690788, -0.12327841818038444}, 1e-10, "one-sample t = scipy");
ok &= expectRow(oneSample.matPval, {0.00014930867649425364, 0.8158714843641037, 0.9066888237538449}, 1e-10, "one-sample p = scipy");
ok &= expectRow(paired.matTstat, {26.0, 0.0, -0.7254762501100115}, 1e-10, "paired t = scipy");
ok &= expectRow(paired.matPval, {1.5724552146685355e-06, 1.0, 0.5006803901900951}, 1e-10, "paired p = scipy");
ok &= expectRow(independent.matTstat, {5.918268896877812, 0.0, -0.34452048127477725}, 1e-10, "independent t = scipy");
ok &= expectRow(independent.matPval, {0.0001473880425533016, 1.0, 0.7375904333691938}, 1e-10, "independent p = scipy");
ok &= expect(oneSample.degreesOfFreedom == 5 && independent.degreesOfFreedom == 10, "df 5 and 10");
ok &= expect(std::fabs(rightTail.matPval(0, 0) - oneSample.matPval(0, 0) / 2.0) < 1e-12, "right-tailed p is half the two-tailed p");

Authors of this file​