Linear Regression Error on Excel

Click For Summary

Discussion Overview

The discussion revolves around calculating the uncertainties associated with the coefficients of a linear regression model in Excel, particularly in the context of experimental physics homework. Participants explore methods to derive these uncertainties and the significance of related statistical measures.

Discussion Character

  • Homework-related
  • Technical explanation

Main Points Raised

  • One participant seeks guidance on how to determine the uncertainties for the coefficients a and b from their linear regression analysis in Excel.
  • Another participant suggests that uncertainties can be calculated manually by setting up the appropriate equations in Excel, referencing external resources for details.
  • A different viewpoint mentions that uncertainty can be inferred from "Goodness of Fit" measures, specifically recommending the use of the R² value available in Excel for assessing the fit quality.
  • Additionally, a participant recommends a textbook that provides an introductory explanation of data fitting and uncertainty, suggesting it may be useful for understanding the concepts better.

Areas of Agreement / Disagreement

Participants present various methods for calculating uncertainties, indicating that there is no consensus on a single approach. Multiple competing views on how to assess uncertainties and the significance of statistical measures remain evident.

Contextual Notes

Some participants reference external resources and textbooks, suggesting that the discussion may depend on the definitions and methods presented in those materials. The discussion does not resolve the specific steps needed to calculate uncertainties directly within Excel.

Who May Find This Useful

This discussion may be useful for students and researchers in experimental physics who are using Excel for data analysis and are interested in understanding how to calculate uncertainties in linear regression coefficients.

Calabi_Yau
Messages
35
Reaction score
1
This is for an experimental physics homework,I am using the latest version of MS Excel. I have a set of data, I perform linear regression on them and it gives me a line y=ax + b.

Given that both a and b have physical significance I would like to know how could I know the uncertainty associated with both a and b, so I could get meaningful results.

How do I do this? The statistics pack seems to give everything but these values.

Any help would be appreciated.
 
Technology news on Phys.org
Uncertainty with regards to coefficients of a model fit to data can be inferred from so called "Goodness of Fit" measures. There are many different ways to approach this however, since you are using Excel, the easiest for way for you is to have Excel display the R2 value. You can do this by either right clicking on your line, selecting Format Trendline and checking off the box next to "Display R-squared value on chart." If you are fitting the line then the same dialog box will have that option on the bottom. Interpretation of the value is fairly straight-forward, a quick Google search will gives lots of discussions.
 
useful textbook

There is a useful textbook explaining things in an introductory manner. Have a look at: "Data Fitting and Uncertainty (A practical introduction to weighted least squares and beyond)", ISBN 978-3-8348-1022-9.
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
Replies
7
Views
2K
  • · Replies 28 ·
Replies
28
Views
3K
  • · Replies 11 ·
Replies
11
Views
5K
  • · Replies 8 ·
Replies
8
Views
3K
Replies
3
Views
3K
  • · Replies 30 ·
2
Replies
30
Views
5K
  • · Replies 23 ·
Replies
23
Views
4K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 64 ·
3
Replies
64
Views
6K