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SUMMARY

The discussion focuses on calculating the error uncertainty of a slope derived from data points using Excel. The user initially employed a method involving maximum and minimum slope calculations based on point uncertainties of +/-0.1, but recognized this approach as inaccurate. A recommended resource is the document on Weighted Least Squares Straight Line Fitting, which provides a more precise methodology for handling uncertainties in y-values when fitting a straight line to data.

PREREQUISITES
  • Understanding of linear regression concepts
  • Familiarity with Excel for data analysis
  • Knowledge of error propagation in measurements
  • Basic statistics, particularly regarding slope calculations
NEXT STEPS
  • Study the Weighted Least Squares method for linear regression
  • Learn about error propagation techniques in statistical analysis
  • Explore advanced Excel functions for statistical modeling
  • Review the document on Fitting Data for practical examples
USEFUL FOR

Data analysts, statisticians, researchers, and anyone involved in quantitative data analysis who needs to accurately calculate slope uncertainties in their datasets.

johnnnnyyy
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So I am a little confused about how to calculate the error uncertainty of a slope. Let's say I have data points (1,2), (2,2.75), (3,3.75), (4,4.7), (5,5.5) which when put in excel gives me a slope of .895. Let's say the error uncertainty for every point is +/-0.1. What I used to do is subtract the maximum possible slope of the first and last points and the minimum possible slope and divide it by 2 to find the error uncertainty. So the max slope would be ((5.5+.1)-(2-.1))/((5-.1)-(1+.1)) and then I would basically do the opposite to find the min slope. But recently I discovered that it is not an accurate way to find the uncertainty of the slope.

Does anybody else no how to find the error uncertainty of a slope?
 
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This appears to be what you're looking for:

https://www.che.udel.edu/pdf/FittingData.pdf‎

Since your data points have uncertainties associated with them (more precisely, with their "y-values"), scroll down to the section Weighted Least Squares Straight Line Fitting which begins on page 8. It might help to skim through the preceding pages first.
 
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