How to calculate the average with uncertainties?

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SUMMARY

The discussion focuses on calculating the average of measurements with associated uncertainties, specifically the values 8.70 ± 0.28, 9.680 ± 0.046, 9.700 ± 0.055, and 9.720 ± 0.067. To compute the weighted average, participants emphasize the necessity of using the formula for weights, which is defined as 1/σ², where σ represents the uncertainty of each measurement. The final calculated average is determined to be 9.45 ± 0.448 meters, highlighting the importance of accounting for varying uncertainties in the averaging process.

PREREQUISITES
  • Understanding of basic statistics and averaging techniques
  • Familiarity with the concept of measurement uncertainty
  • Knowledge of weighted averages and their calculation
  • Basic proficiency in mathematical notation and symbols
NEXT STEPS
  • Research the concept of weighted averages in statistics
  • Learn about different methods for calculating uncertainties in measurements
  • Explore the application of the formula 1/σ² in various statistical contexts
  • Study examples of averaging measurements with varying degrees of accuracy
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Students in physics or engineering, researchers dealing with experimental data, and anyone interested in accurately calculating averages with uncertainties.

Tyler S
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Homework Statement


How to calculate the average given the uncertainties in each measurement 8.70 +/- 0.28, 9.680 +/- 0.046, 9.700 +/- 0.055, 9.720 +/- 0.067?

Homework Equations

The Attempt at a Solution


I know I add the values and divide by 4. I also know I add the absolute uncertainties but idk if I divide them by 4. Please help I've gotten 9.45 +/- 0.448 meters
 
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Hello Tyler, :welcome:

In the case off different accuracies, you have to weight the measurements when averaging. The appropriate weight of a measurement is ##1\over \sigma^2##.
Here, ##\sigma## is the (estimated) inaccuracy
 
Last edited:
BvU said:
It's "weight the measurements".
BvU said:
Here, σ is the (estimated) accuracy
Well, it's not so much the accuracy as the inaccuracy.
 
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