CONFIDENCE.T function - The function returns the confidence interval of the population by using the Student's t-distribution in Excel

The following article introduces you to the CONFIDENCE.T function - one of the functions in the statistical group is very popular in Excel.

CONFIDENCE.T function - The function returns the confidence interval of the population by using the Student's t-distribution in Excel Picture 1

Description: The function returns the confidence interval of the population by using the Student's t-distribution. Support functions from Excel 2010 onwards.

Syntax: CONFIDENCE.NORM (alpha, standard_dev, size)

Inside:

- alpha: The critical level to calculate the confidence level, with confidence level = 100 * (1- alpha) , is the required parameter .

- standard_dev: The overall standard deviation for the data range, and considered to have been determined, is the required parameter.

- size: Sample size , is a required parameter.

Attention:

- If any of the parameters' values ​​are not numeric -> the function returns the #VALUE! Error value .

- If alpha ≤ 0 or alpha ≥ 1 -> the function returns the #NUM! Error value

- If standard_dev ≤ 0 -> the function returns the #NUM! Error value

- If size is not an integer -> it is truncated to an integer.

- If size = 1 -> the function returns the # DIV / 0 error value !

For example:

Calculate the average overall confidence interval based on the Student's t-distribution with the data in the table below:

CONFIDENCE.T function - The function returns the confidence interval of the population by using the Student's t-distribution in Excel Picture 2

- In the cell to calculate, enter the formula: = CONFIDENCE.T (D6, D7, D8)

CONFIDENCE.T function - The function returns the confidence interval of the population by using the Student's t-distribution in Excel Picture 3

- Press Enter -> the overall confidence interval for the population is:

CONFIDENCE.T function - The function returns the confidence interval of the population by using the Student's t-distribution in Excel Picture 4

- Where alpha ≤ 0 or alpha ≥ 1 -> the function returns the #NUM! Error value

CONFIDENCE.T function - The function returns the confidence interval of the population by using the Student's t-distribution in Excel Picture 5

- Where size = 1 -> the function returns the error value #NUM!

CONFIDENCE.T function - The function returns the confidence interval of the population by using the Student's t-distribution in Excel Picture 6

Above are instructions and some specific examples when using the CONFIDENCE.T function in Excel.

Good luck!