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How to use the CONFIDENCE.NORM function in Excel office 365?

#tousetheconfidenceno #excel #excelfunctions

CONFIDENCE.NORM takes the 3 numerical argument values of alpha, standard deviation, and size of the sample dataset. The function returns the margin of error for the given alpha value. In this post, we will explain to you how to use CONFIDENCE.NORM Function In Excel Office 365. Let’s see them below!! Get an official version of MS Excel from the following link: https://www.microsoft.com/en-in/microsoft-365/excel

CONFIDENCE.NORM Function syntax 

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

  • alpha : value calculated using confidence level. 1 – confidence level.
  • standard_dev : standard deviation for the given dataset.
  • size : sample size for the dataset.

Example

  • Firstly, you need to create the sample data with mean, standard deviation and size of the dataset.

Sample data

  • You have to calculate the margin of error for the confidence level 90%.
  • Here, Alpha would be calculated using the formula (1-confidence level) and use this alpha argument in the formula.

The formula for 90% confidence level:

=CONFIDENCE.NORM ( E2, B2, B3)
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confidence level 90%

  • Now, the function returns the value 0.6579 which will be the margin of error for the 90% confidence level.
  • You need to calculate the margin of error for the confidence level 95%.

The formula for 95% confidence level:

=CONFIDENCE.NORM ( E3, B2, B3)
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Confidence level 95%

  • The function returns the value 0.7839 which will be the margin of error for the 95% confidence level.
  • Now, you need to calculate the margin of error for the confidence level 99%.

The formula for 99% confidence level:

=CONFIDENCE.NORM ( E4, B2, B3)
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The confidence level for 99%

  • Then, you can see the increasing the confidence level value, and alpha value gets decreases but the margin of error increases.
  • Now, you need to calculate the confidence interval around the mean for the dataset.

The formula for the lower limit of interval:

= 36 - H2
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Lower limit value

The formula for the upper limit of interval:

= 36 + H2
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Upper limit value

  • At last, you have to calculate the confidence interval around the mean of the dataset for both confidence level 95% and 99%.

For all confidence level

NOTE:

  • The CONFIDENCE.NORM Function only works with numbers.
  • If any argument other than cumulative is non-numeric , the function returns #VALUE! error.
  • The function returns #NUM! Error.
    • If alpha < 0
    • and If alpha > 1
  • The value in decimal and value in percentage is the same value in Excel and convert the value to percentage , if required.
  • Finally, you can feed the arguments to the function directly or using the cell reference, as explained in the example.

Wrap-Up

Hope you understood how to use CONFIDENCE.NORM Function In Excel Office 365. Please feel free to state your query or feedback for the above article. Thank you for Reading!! To learn more, check out Geek Excel!! *and Excel Formulas *!!

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