T.DIST.2T in Collabora Office: Calculate a Two-Tailed Student t Probability
Use Collabora T.DIST.2T for symmetric outside-tail probability, compare one-tail results and audit critical values.
Verification status: See the evidence and test scope described in this guide. How formula examples are checked
Quick answer: =T.DIST.2T(1;10) has independently expected result approximately 0.340893132. It is the total probability outside the interval from -1 to 1 under a ten-degree t model.
Syntax and the nonnegative magnitude
=T.DIST.2T(Number; DegreesFreedom)
Number is the nonnegative magnitude of a t threshold. DegreesFreedom selects the distribution. Both arguments are required; there is no cumulative-or-density option. The function returns a probability from the two symmetric tails together.
The dedicated Collabora help documents a two-tailed distribution. Current source corroboration approximately floors the degree count and rejects degrees below one or a negative Number. Use positive integer degrees and a nonnegative threshold rather than passing a signed statistic directly.
If a separately calculated t statistic is signed and the intended test is genuinely two-sided, ABS(t) expresses its magnitude. This transformation is appropriate because of that chosen test, not a universal way to repair any unexpected sign.
Example 1: reproduce the official result
=T.DIST.2T(1;10) targets approximately 0.340893132. The right-tail probability above +1 is approximately 0.170446566; symmetry places the same probability below -1.
The sum of those two probabilities gives the documented two-tail result. Do not multiply T.DIST.2T by two again: the function has already included both tails.
The result does not say that a hypothesis has a 34.1% chance of being true. It describes how much probability lies in the specified model’s outside regions.
Example 2: build a decreasing magnitude table
Put 0, 1 and 2 in A2:A4. Enter =T.DIST.2T(A2;10) in B2 and fill down. Independent targets are approximately 1, 0.340893132 and 0.073388035.
Larger magnitudes leave less probability beyond the two thresholds. At zero, the two tails together cover the whole continuous distribution, giving a mathematical target of one.
For these nonnegative inputs, =2*T.DIST.RT(A2;10) in C2 provides a matching independent control. For a signed negative input to the right-tail function, that doubled right tail would answer a different question and can exceed one.
Advanced application: compare central and outside probability
At magnitude two with ten degrees, the central interval from -2 to 2 has probability approximately 0.926611965. Adding this to the two-tail value approximately 0.073388035 targets one.
The central calculation can be written =T.DIST(2;10;1)-T.DIST(-2;10;1). Both calls must request cumulative mode. Subtracting two equal density values would yield zero and would not calculate area.
Keep labels such as “Central interval” and “Outside both tails” next to the respective outputs. This avoids confusing a large central probability with a large p-value.
Advanced application: check a two-sided critical value
Put =T.INV.2T(0.05;10) in F2. The independent threshold is approximately 2.228138852. =T.DIST.2T(F2;10) should target 0.05.
The matching upper-tail probability is 0.025, and the left-tail cumulative probability at the positive threshold is 0.975. These are different encodings of the same symmetric boundary, not three competing significance levels.
If an observed t value is -2.228138852, its magnitude reaches the corresponding lower boundary. Preserve the original signed statistic elsewhere so the estimated effect direction is not lost.
Errors and troubleshooting
A negative threshold follows the current source’s illegal-argument path for this two-tail function. The guide does not certify the exact localized error display. Use an explicitly justified magnitude and check the degree count rather than silently changing the scientific question.
A two-tail probability does not validate independence, normality of the relevant errors or a sample design. These assumptions and any decision rule must be established separately. Extreme probabilities, native convergence and all text/blank conversions remain outside the independent examples.
Availability and evidence
The exact function is documented in Collabora Office 26.04 desktop help. That documentation snapshot was retrieved on 2026-10-13 and hash-verified on October 15, 2026. It does not establish Online or mobile support. First introduction and last functioning release are unknown in this evidence.
Additional implementation statements come from Collabora’s current engine source, retrieved October 15, 2026. This moving-main source is corroboration, not a pinned desktop 26.04 binary or a native execution. No native Collabora Office run occurred. Worked outputs are independent mathematical expectations.
Formulas use English names and semicolon separators. The help identifies namespace COM.MICROSOFT.T.DIST.2T, outside its cited OpenFormula 1.3 standard; that does not establish identical behavior in another application.