Returns the t-value of the Student's t-distribution as a function of the probability and the degrees of freedom.
Probability is the probability associated with the two-tailed Student's t-distribution.
Degrees_freedom is the number of degrees of freedom with which to characterize the distribution.
- If either argument is nonnumeric, TINV returns the #VALUE! error value.
- If probability < 0 or if probability > 1, TINV returns the #NUM! error value.
- If degrees_freedom is not an integer, it is truncated.
- If degrees_freedom < 1, TINV returns the #NUM! error value.
- TINV returns that value t, such that P(|X| > t) = probability where X is a random variable that follows the t-distribution and P(|X| > t) = P(X < -t or X > t).
- A one-tailed t-value can be returned by replacing probability with 2*probability. For a probability of 0.05 and degrees of freedom of 10, the two-tailed value is calculated with TINV(0.05,10), which returns 2.28139. The one-tailed value for the same probability and degrees of freedom can be calculated with TINV(2*0.05,10), which returns 1.812462.
Note In some tables, probability is described as (1-p).
Given a value for probability, TINV seeks that value x such that TDIST(x, degrees_freedom, 2) = probability. Thus, precision of TINV depends on precision of TDIST. TINV uses an iterative search technique. If the search has not converged after 100 iterations, the function returns the #N/A error value.
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||Probability associated with the two-tailed Student's t-distribution
||Degrees of freedom
||t-value of the Student's t-distribution for the terms above (1.959999998)