Explain to me a few things about loot.xml

[Hollowprime]

If I understand correctly, the gamestage affects the loot. So I have a few questions:

What do these lines do?

<lootprobtemplate name="probTemplate1.0">

<lootprobtemplate name="probTemplate0.75">

<lootprobtemplate name="probTemplate0.5">

<lootprobtemplate name="probTemplate0.5to1.0">

And I'd also like to know which line(s) of code affect the loot chance of the bags (the base is 0.02 in another xml file). Does the rarity of the items in the loot bag as well as its chance to drop from zombies increase with gamestage?

Thanks for your time.