Solved – Use Empirical CDF vs Distribution CDF

cumulative distribution functiondata visualizationdensity functiondistributions

NOTE: I purposely did not label the axis due to pending publications. The line colors represent the same data in all three plots.
I fitted my data using a negative binomial distribution to generate a pdf. I am happy with the pdf and meets my research needs. PDF plot:

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For when reporting the CDF, should I use the empirical or fitted CDF? There are slight differences between the empirical and fitted CDF, specifically at x = 40, the yellow and cyan lines intersect in the empirical distribution, but not the fitted.

Empirical:
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Negative Binomial CDF:
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Best Answer

Personally, I'd favour instead showing the fit of the theoretical to the empirical distribution using a set of P-P plots or Q-Q plots.

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