Thanks for the feedback and sorry, it could have been clearer that we distinguish between "figure" and "toy". I didn't know how to add any extra explanations to the image in Reddit. Thus the blog post contains further details.

Agreed, I tried in https://mhoehle.github.io/blog/2016/12/23/surprise.html to calculate a functional shape.

The right hand plot gives an indication of such a plot. The blog post, where the figure is taken from, contains such a smoothed line obtained from applying some machine learning classification algorithm to the task (deliberate overkill! :-)).

http://staff.math.su.se/hoehle/blog/figure/source/2016-12-23-surprise/CLASSIFIEROUTPUT-1.png

Source: https://mhoehle.github.io/blog/2016/12/23/surprise.html

Not sure I fully understand the comment, but the content of the egg is either some kind of toy or a figure. So what varies is the content of the egg, not the chocolate. For some example pictures see https://mhoehle.github.io/blog/2016/12/23/surprise.html.

It's either "plastic junk" or a "cool" collectable figure, which is usually part of a figure series! Some of the figures are collector's items and can be quite valuable (see e.g. https://www.eierlei-shop.de/ (in German)).

Complete Blog Post text as well as Data Source for the n=79 eggs & R-Script to perform the analyses:

suRprise! - Classifying Kinder Eggs by Machine Learning