TTEST

TTEST is the pre-2010 spelling of T.TEST and Microsoft's TTEST page carries the same worked example: a paired, two-tailed test on the nine pairs above, published as 0.196016. DERIVATION (nothing here comes from a statistics package's t-test routine): the paired t-statistic is dbar/(sd/sqrt(n)) over the nine pairwise differences -3,-15,2,6,-5,-3,-3,-13,4, whose mean is -30/9 and whose sample standard deviation uses the n-1 divisor; that gives t = -1.4106912317171967 on 8 degrees of freedom. The p-value is then 2*(1 - F(|t|)) evaluated on this batch's doubly-cross-checked Student t CDF -- the regularized incomplete beta AND an independent numerical quadrature of the t density, agreeing to 25 digits -- giving 0.1960157849252821063357. scipy.stats.ttest_rel reproduces both the statistic and the p-value to double precision as a third check. Microsoft's page was read live on 2026-08-31 at https://support.microsoft.com/en-us/excel/functions/ttest-function. FETCH NOTE FOR THIS BATCH: batch F recorded every /en-us/office/<name>-function-<guid> URL returning Microsoft's 'Sorry, the page you're looking for can't be found' body; today BOTH paths serve the article again -- the GUID form redirects to /en-us/excel/functions/<slug>-function -- and every page cited in this batch came back complete (217-223 KB) in one or two attempts, with no 87 KB stub responses. Nothing here is sourced from a search snippet or a mirror.

Asserted at twelve places from the derivation: 0.196015784925.

The TTEST page's Important box directs readers to T.TEST, and the two are documented as the same test with the same argument order. A structural assertion with no derived constant, checking the engine's two spellings against each other. THIS IS THE CASE THE LEGACY NAMES EXIST IN THIS CORPUS FOR: batch F found NEGBINOMDIST and NEGBINOM.DIST disagreeing with each other on a documented-invalid input, so a compatibility alias drifting from its modern twin is a real and observed failure, not a hypothetical one.

The alias check repeated on the argument combination the published examples never exercise -- one-tailed, unequal variance -- because that is where a drifted alias would most plausibly survive undetected.

The TTEST Remarks publish the same rule as T.TEST: "If array1 and array2 have a different number of data points, and type = 1 (paired), TTEST returns the #N/A error value."

The Remarks publish: "If tails is any value other than 1 or 2, TTEST returns the #NUM! error value."

TTEST is the pre-2010 spelling of T.TEST and Microsoft's TTEST page carries the same worked example: a paired, two-tailed test on the nine pairs above, published as 0.196016. DERIVATION (nothing here comes from a statistics package's t-test routine): the paired t-statistic is dbar/(sd/sqrt(n)) over the nine pairwise differences -3,-15,2,6,-5,-3,-3,-13,4, whose mean is -30/9 and whose sample standard deviation uses the n-1 divisor; that gives t = -1.4106912317171967 on 8 degrees of freedom. The p-value is then 2*(1 - F(|t|)) evaluated on this batch's doubly-cross-checked Student t CDF -- the regularized incomplete beta AND an independent numerical quadrature of the t density, agreeing to 25 digits -- giving 0.1960157849252821063357. scipy.stats.ttest_rel reproduces both the statistic and the p-value to double precision as a third check. Microsoft's page was read live on 2026-08-31 at https://support.microsoft.com/en-us/excel/functions/ttest-function. FETCH NOTE FOR THIS BATCH: batch F recorded every /en-us/office/<name>-function-<guid> URL returning Microsoft's 'Sorry, the page you're looking for can't be found' body; today BOTH paths serve the article again -- the GUID form redirects to /en-us/excel/functions/<slug>-function -- and every page cited in this batch came back complete (217-223 KB) in one or two attempts, with no 87 KB stub responses. Nothing here is sourced from a search snippet or a mirror.

Asserted at twelve places from the derivation: 0.196015784925.

The TTEST page's Important box directs readers to T.TEST, and the two are documented as the same test with the same argument order. A structural assertion with no derived constant, checking the engine's two spellings against each other. THIS IS THE CASE THE LEGACY NAMES EXIST IN THIS CORPUS FOR: batch F found NEGBINOMDIST and NEGBINOM.DIST disagreeing with each other on a documented-invalid input, so a compatibility alias drifting from its modern twin is a real and observed failure, not a hypothetical one.

The alias check repeated on the argument combination the published examples never exercise -- one-tailed, unequal variance -- because that is where a drifted alias would most plausibly survive undetected.

The TTEST Remarks publish the same rule as T.TEST: "If array1 and array2 have a different number of data points, and type = 1 (paired), TTEST returns the #N/A error value."

The Remarks publish: "If tails is any value other than 1 or 2, TTEST returns the #NUM! error value."

TTEST is the pre-2010 spelling of T.TEST and Microsoft's TTEST page carries the same worked example: a paired, two-tailed test on the nine pairs above, published as 0.196016. DERIVATION (nothing here comes from a statistics package's t-test routine): the paired t-statistic is dbar/(sd/sqrt(n)) over the nine pairwise differences -3,-15,2,6,-5,-3,-3,-13,4, whose mean is -30/9 and whose sample standard deviation uses the n-1 divisor; that gives t = -1.4106912317171967 on 8 degrees of freedom. The p-value is then 2*(1 - F(|t|)) evaluated on this batch's doubly-cross-checked Student t CDF -- the regularized incomplete beta AND an independent numerical quadrature of the t density, agreeing to 25 digits -- giving 0.1960157849252821063357. scipy.stats.ttest_rel reproduces both the statistic and the p-value to double precision as a third check. Microsoft's page was read live on 2026-08-31 at https://support.microsoft.com/en-us/excel/functions/ttest-function. FETCH NOTE FOR THIS BATCH: batch F recorded every /en-us/office/<name>-function-<guid> URL returning Microsoft's 'Sorry, the page you're looking for can't be found' body; today BOTH paths serve the article again -- the GUID form redirects to /en-us/excel/functions/<slug>-function -- and every page cited in this batch came back complete (217-223 KB) in one or two attempts, with no 87 KB stub responses. Nothing here is sourced from a search snippet or a mirror.

Asserted at twelve places from the derivation: 0.196015784925.

The TTEST page's Important box directs readers to T.TEST, and the two are documented as the same test with the same argument order. A structural assertion with no derived constant, checking the engine's two spellings against each other. THIS IS THE CASE THE LEGACY NAMES EXIST IN THIS CORPUS FOR: batch F found NEGBINOMDIST and NEGBINOM.DIST disagreeing with each other on a documented-invalid input, so a compatibility alias drifting from its modern twin is a real and observed failure, not a hypothetical one.

The alias check repeated on the argument combination the published examples never exercise -- one-tailed, unequal variance -- because that is where a drifted alias would most plausibly survive undetected.

The TTEST Remarks publish the same rule as T.TEST: "If array1 and array2 have a different number of data points, and type = 1 (paired), TTEST returns the #N/A error value."

The Remarks publish: "If tails is any value other than 1 or 2, TTEST returns the #NUM! error value."