Acceptable range for the goodness of fit

3 次查看（过去 30 天）

显示更早的评论

Mitra Taghizadeh 2022-4-15

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit

⋮

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit

评论： Star Strider 2022-4-16

Hello every one,

I have estimated sets of data that should be compared to the reference data. I used the MATLAB code of 'goodnessOfFit' with the NRMSE and I got these values: -0.1716 and 0.3712. I want to know what is the acceptable value range? and which one is better?

Is there any more underestandable way to know the goodness of fit?

7 个评论
显示 5更早的评论隐藏 5更早的评论

Walter Roberson 2022-4-15

此评论的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit#comment_2103770

⋮

链接

此评论的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit#comment_2103770

For this purpose we need to know if you were using R2020a or later, or if you are using an earlier version of MATLAB.

Star Strider 2022-4-15

此评论的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit#comment_2103795

⋮

链接

此评论的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit#comment_2103795

I would rely more on the confidence intervals for the parameters and the fitted curve, or other derived statistics (such as p-values).

Mitra Taghizadeh 2022-4-15

此评论的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit#comment_2103850

⋮

链接

此评论的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit#comment_2103850

@Walter Roberson

Hi Walter,

I'm using 2019b.

Mitra Taghizadeh 2022-4-15

此评论的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit#comment_2103855

⋮

链接

此评论的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit#comment_2103855

@Star Strider

Just for clarification I should say some more explenation.

Actually, I have two sets of experimental data for displacement and I have fitted two curves on them using cftool. Now obtained one graph by combination of these two obtained graphs and I want to know how much this new graph is fitted to the experimental data.

Do you think that I should use P-value? How can I use it?

Star Strider 2022-4-15

此评论的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit#comment_2104470

⋮

链接

此评论的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1697015-acceptable-range-for-the-goodness-of-fit#comment_2104470

The p-value should be less than 0.05 conventionally to determine significance.

The confidence intervals would be more revealing, because they easily determine if a parameter is significantly different from zero (both confidence intervals of the same sign).

If you are comparing two different models with the same number of parameters, use the Likelihood-ratio test to determine which is best.

If the two models have different numbers of parameters, this gets complicated quickly. See your Statistics Department for guidance in that event.

Mitra Taghizadeh 2022-4-15