How to Calculate Absolute Error

Step-by-Step Guide

1. 1

   Step 1: Set up the formula for calculating the absolute error.

   The formula is Δx=x0−x{\displaystyle \Delta x=x_{0}-x}, where Δx{\displaystyle \Delta x} equals the absolute error (the difference, or change, in the measured and actual value), x0{\displaystyle x_{0}} equals the measured value, and x{\displaystyle x} equals the actual value., The actual value should be given to you.
   
   If not, use a standardly accepted value.
   
   Substitute this value for x{\displaystyle x}.
   
   For example, you might be measuring the length of a football field.
   
   You know that the actual, or accepted length of a professional American football field is 360 feet.
   
   So, you would use 360 as the actual value:Δx=x0−360{\displaystyle \Delta x=x_{0}-360}. , This will be given to you, or you should make the measurement yourself.
   
   Substitute this value for x0{\displaystyle x_{0}}.
   
   For example, if you measure the football field and find that it is 357 feet long, you would use 357 as the measured value:Δx=357−360{\displaystyle \Delta x=357-360}. , Since absolute error is always positive, take the absolute value of this difference, ignoring any negative signs.This will give you the absolute error.
   
   For example, since Δx=357−360=−3{\displaystyle \Delta x=357-360=-3}, the absolute error of your measurement is 3 feet.
2. 2

   Step 2: Plug the actual value into the formula.

3. 3

   Step 3: Find the measured value.

4. 4

   Step 4: Subtract the actual value from the measured value.

Detailed Guide

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