Standard deviation from measures with different uncertainty

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SUMMARY

The discussion focuses on calculating the standard deviation of measurements with varying uncertainties, specifically for the values L=5±0.2, L=5.1±0.1, L=5.2±0.3, L=5.3±0.1, and L=5.4±0.2. The user initially calculated the arithmetic mean, variance, and standard deviation assuming uniform uncertainty, but sought guidance on handling differing uncertainties. The recommended approach involves using the formula ΔL=√(V(L)+U²(L)), where U(L) represents the measurement uncertainty for each result. However, the user requires further clarification on applying this method when uncertainties differ.

PREREQUISITES
  • Understanding of basic statistics, including mean, variance, and standard deviation.
  • Familiarity with measurement uncertainty concepts in experimental physics.
  • Knowledge of combining uncertainties in measurements.
  • Ability to interpret and apply formulas related to statistical analysis.
NEXT STEPS
  • Research methods for combining uncertainties in measurements with different variances.
  • Learn about the propagation of uncertainty in experimental results.
  • Explore statistical software tools for calculating weighted averages and standard deviations.
  • Study the principles of error analysis in physical measurements.
USEFUL FOR

Students in physics or engineering, researchers conducting experiments with varying measurement uncertainties, and anyone involved in statistical analysis of experimental data.

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Homework Statement


i have a few results of measurements, with different measurement uncertainty: L=5\pm0,2, L=5,1\pm0,1,L=5,2\pm0,3,L=5,3\pm0,1,L=5,4\pm0,2 and how can i count standard deviation and final result of measurement with uncertainty?

The Attempt at a Solution


i counted arithmetic mean, variance and standard deviation of all results, if they were the same I would just do this like this \Delta L=\sqrt{V(L)+U^2(L)} where U(L) is measurement uncertainty of a single result, but what to do when they are different?
 
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There's a good explanation of how to treat the uncertainty here
http://www.rit.edu/cos/uphysics/uncertainties/Uncertaintiespart1.html#estimate
 
Last edited by a moderator:
thanks for this link, it is very helpful, but there arent solution for what to do with this thing that i mentioned, do you have any other idea?
 

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