Recent content by Koen Van de moortel

  1. Koen Van de moortel

    Is there a good tool for finding the best curve to fit my data?

    I don't know all the inventions of the number crunchers who are - in my modest opinion - making things often way too complicated, but I did get the courses we needed in physics, about probability, distributions, error propagation, least squares regression, numerical analysis, etc. And I do have...
  2. Koen Van de moortel

    Is there a good tool for finding the best curve to fit my data?

    You said "THE" empirical distribution. I can only imagine AN empirical distribution. And that doesn't explain anything about the underlying mechanism, just fitting a polynome doesn't explain anything. Seriously. And my graphs in #42 are just normal OLS fittings of the given data with the...
  3. Koen Van de moortel

    Is there a good tool for finding the best curve to fit my data?

    All I can say is that it fits a lot obviously better than the author's graph. I just wondered how that could be so strange, so I tried it myself. I'm not claiming to know if this has to be a normal distribution; that will not be an easy thing to calculate I guess, and as above mentioned, it...
  4. Koen Van de moortel

    Is there a good tool for finding the best curve to fit my data?

    I know all this. It's not the same as my MDLS method. What 's wrong with the Deming method is that it treats x and y as if they have the same dimension and units. But how can you define an orthogonal distance if e.g. x=current and y=voltage?
  5. Koen Van de moortel

    Is there a good tool for finding the best curve to fit my data?

    This is what I get, 1) including the zeroes (for which I had to give an error of 1), 2) without the zeroes, and in each case with fixed parameter N (should be the total of wins = 464) and with free N. BTW, this is ordinary least squares regression with iteration.
  6. Koen Van de moortel

    Is there a good tool for finding the best curve to fit my data?

    @GretaGarbo What do you mean? "The distribution for the data"? This is an example of a fitted Gauss distribution, included with the program.
  7. Koen Van de moortel

    Is there a good tool for finding the best curve to fit my data?

    It's published in the above mentioned journal, and I can assure you that I have done extensive research to test it. See: https://www.researchgate.net/profile/Koen-Van-De-Moortel/research And, you can test the software 25 days for free, with your own data. I'm curious to see your findings!
  8. Koen Van de moortel

    Comparing two means derived from the same sample

    BTW, Corpulence index (m/h³) is a better variable than BMI (m/h²); see: https://www.researchgate.net/publication/358736303_The_Body_Mass_Index_recalculated
  9. Koen Van de moortel

    Is there a good tool for finding the best curve to fit my data?

    @GretaGarbo Yes, the software is meant to find the best fitting parameters for a number of models, by iteration and taking measurement imprecisions into account (most of the others just neglect that). In the current version, you can also find the best fitting Gauss distribution or a mix of two...
  10. Koen Van de moortel

    Regression Checklist

    The most important is that you have an idea what kind of function describes the relationship between your data! Otherwise you are just guessing around.
  11. Koen Van de moortel

    Help! What analysis should be performed on a dataset like this?

    Maybe it's too late, but this is what I would do: a linear fit of heat output vs work level/mass. What do think? Does it make sense?
  12. Koen Van de moortel

    Help! What analysis should be performed on a dataset like this?

    I would add to this: you can't nor shouldn't force the residuals to be normally distributed. If they are not normally distributed, it's just an indication that another variable is influencing your dependent variable.
  13. Koen Van de moortel

    How to find the best regression model

    The only good model is one that is supported by a physical theory! All the others are just guessing work.
  14. Koen Van de moortel

    Plotting Error Bars

    This is automatically done in this software: www.lerenisplezant.be/fitting.htm