Physics Experiment Linear Regression Issue

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SUMMARY

The forum discussion centers on a physics experiment involving electron diffraction and the analysis of data through linear regression. The user reports that the slope of their linear regression is lower than expected and diverges significantly from individual calculated values. The analysis suggests that the linear regression may not accurately represent the data due to potential misfit or underlying trends not captured by the model. Alternative methods such as non-linear regression or logarithmic fitting are recommended for more accurate data representation.

PREREQUISITES
  • Understanding of linear regression analysis
  • Familiarity with electron diffraction experiments
  • Knowledge of statistical data fitting techniques
  • Basic proficiency in using data analysis software (e.g., Python with NumPy and SciPy)
NEXT STEPS
  • Explore non-linear regression techniques using Python's SciPy library
  • Learn about logarithmic fitting methods for data analysis
  • Investigate the assumptions and limitations of linear regression models
  • Review best practices for data visualization to identify trends
USEFUL FOR

Students conducting physics experiments, data analysts working with regression models, and researchers seeking to improve data fitting accuracy in experimental results.

tsumi
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Homework Statement



Hello, I have done a laboratorial experiment (electron diffraction) and I've been doing the analysis of the obtained data.

I have plotted the data obtained experimentally, and the slope of the obtained linear regression should give a certain value.

What's happening is that the slope of the linear regression gives a value inferior to any of the individually calculated values, is this normal? and this value is quite different from the theoretically expected one, while all the individual values are much closer to the expected one. This is my only question.

Thank you for your attention

Homework Equations





The Attempt at a Solution

 
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It is possible that the linear regression line does not accurately depict the data points, since it is designed to fit the data in a way that minimizes the sum of the squares of the vertical distances between the points and the regression line. It could be that the points are not well-suited for a linear regression, or that there is an underlying trend that is not being properly captured by the linear regression. Additionally, it is possible that the linear regression is giving an accurate representation of the data, but that the individual values are not. You may want to consider other forms of analysis, such as non-linear regression or a logarithmic fit.
 

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