I guess it is very hard to have a good understanding of the paper without learning your model in detail. I guess there are something general I can ask about:
When do you decide to develop your own model instead of using those already developed? It looks it takes much effort to develop a good and reliable model that can simulate data.
When you compare your model against others, what do you weight heavily? Do you have anything to share with us? Thanks!
I guess it is very hard to have a good understanding of the paper without learning your model in detail. I guess there are something general I can ask about: