The TDIST function in Google Sheets is a powerful tool used for statistical analysis, specifically for calculating probabilities related to Student’s t-distribution. This function is essential for researchers and statisticians when performing hypothesis testing or assessing statistical significance in smaller sample sizes.

Syntax

TDIST(x, degrees_freedom, tails)

• x: The t-value for which you want to calculate the probability.
• degrees_freedom: The number of degrees of freedom associated with the data set.
• tails: Specifies the type of distribution. Use 1 for one-tailed tests or 2 for two-tailed tests.

Example #1

=TDIST(2.5, 10, 2)

This function calculates the two-tailed probability for a t-value of 2.5 with 10 degrees of freedom. The result is approximately 0.027.

Example #2

=TDIST(1.645, 30, 1)

This function returns the one-tailed probability for a t-value of 1.645 with 30 degrees of freedom. The result is about 0.05.

Example #3

=TDIST(-2.0, 25, 2)

Here, the function computes the two-tailed probability for a t-value of -2.0 with 25 degrees of freedom. The result is approximately 0.05.

Error handling

• NUM!: Occurs when the degrees of freedom are not a positive integer or if the tails argument is not 1 or 2.
• VALUE!: This error happens if any of the arguments are non-numeric, such as text or empty cells.

Conclusion

The TDIST function is crucial for statistical analysis, particularly for studies that rely on smaller sample sizes and require the use of t-distribution. By understanding how to implement TDIST correctly, researchers can evaluate hypotheses more effectively and make better data-driven decisions.