How does auto-selection work?

Boss movesets are considered but attacker movesets don't seem to be factored in.

Poorly

My observations:

It chooses double resists over single resists even if the stats would make the single better. ((Level 28 Omastar vs Level 38 Vaperon))

It chooses one bar moves over 2 bar moves even when same species and the 2 bar move one is higher level. Dracometer and even Hurricane Dragonites will show even if you have higher level Outrage ones.

The auto select algorithm seems to highly favor mons with good survivability and resistances to whatever you're going up against. My Lugia, Aggron, and Metagross get auto selected all the time.

From my experience it seems to consider in order of importance:
1. Resistance against boss charge move (double resistance heavily preferred like someone said already)
2. Resistance against boss fast move (I observed this with Suicune where it would give me a maxed Espeon if the fast move was ES)
3. General tankiness (loves Lugia, Ho-Oh, Tyranitar, Rhydon etc.)
4. Attacker charge move (Prefers 1-bar moves, the faster the better. My theory is that the game calculates raw charge move DPS because that explains why Stone Edge and Hydro Pump are its absolute favorites)
5. Attacker fast move (Maybe, I think I've seen it prefer RS Rhydons against gym Blisseys)

I think Niantic designed it that way so that the chance of wasting the pass is higher.
Raid: should focus on DPS whereas the autoselect pick survivablity and 1 bar charge move. I always correct my raid team

I've had 5 Tyranitars selected in a gym battle, where the first defender was a Hariyama with double fighting moves.