CONFIDENCE.TDAX Function (Statistical)

Returns the confidence interval for a population mean, using a Student’s t distribution.

Syntax

CONFIDENCE.T ( <Alpha>, <Standard_dev>, <Size> )
Parameter Attributes Description
Alpha

The significance level used to compute the confidence level. The confidence level equals 100*(1 – alpha)%, or in other words, an alpha of 0.05 indicates a 95 percent confidence level.

Standard_dev

The population standard deviation for the data range and is assumed to be known.

Size

The sample size.

Return values

Scalar A single decimal value.

Returns the confidence interval for a population mean, using a Student’s t distribution.

Examples

```--  CONFIDENCE.NORM returns the confidence interval
--  for a population mean, assuming a normal distribution
--  CONFIDENCE.T uses a Student's T distribution instead
--
--      CONFIDENCE.NORM ( Alpha, StandardDev, SampleSize )
--
--  Confidence level equals 100*(1-alpha)%
--  Alpha 0.05 indicates a 95% confidence level
DEFINE
TABLE SampleData = { 2, 4, 4, 4, 5, 5, 7, 9 }
VAR Mean         = AVERAGE ( SampleData[Value] )
VAR StandardDev  = STDEV.S ( SampleData[Value] )
VAR SampleSize   = COUNTROWS ( SampleData )
VAR Alpha        = 0.05 -- 95% confidence level
EVALUATE
{
( "AVERAGE",          Mean ),
( "STDEV.S",          StandardDev ),
( "CONFIDENCE.NORM",  CONFIDENCE.NORM ( Alpha, StandardDev, SampleSize ) ),
( "CONFIDENCE.T",     CONFIDENCE.T    ( Alpha, StandardDev, SampleSize ) )
}

```
Value1 Value2
AVERAGE 5.00
STDEV.S 2.14
CONFIDENCE.NORM 1.48
CONFIDENCE.T 1.79

Last update: Jul 12, 2024     » Show contributors

Contributors: Alberto Ferrari, Marco Russo

Microsoft documentation: https://docs.microsoft.com/en-us/dax/confidence-t-function-dax

Context Transition

This function performs a Context Transition if called in a Row Context. Click to read more.

Row Context

This expression is executed in a Row Context. Click to read more.

Not recommended

The use of this function is not recommended. See Remarks and Related functions for alternatives.

Not recommended

The use of this parameter is not recommended.

Deprecated

This function is deprecated. Jump to the Alternatives section to see the function to use.

Volatile

A volatile function may return a different result every time you call it, even if you provide the same arguments. Click to read more.

Deprecated

This parameter is deprecated and its use is not recommended.

DirectQuery compatibility

Limitations are placed on DAX expressions allowed in measures and calculated columns.
The state below shows the DirectQuery compatibility of the DAX function.

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