I'm trying to get a feel for strategy with PS and wrap my head around top, middle and bottom feeding.

Assuming technology is exactly the same between the two countries, is it just army vs army? Or 1.5army vs army when PS?

I couldn't find it in the wiki, but I seem to remember there being a attacking or defending bonus depending on the size of the two countries.

Anyone have formulas or general pointers to share?

1.5 army vs 1 army when ps, no att/def bonuses depending country size.

if you are looking for attack formula its your forces + possible govt bonus (dict +25%, rep -10%) + weap tech + ps + off allies forces (max 25% of their available forces and can't more than double your forces) and defending is same except no ps and off allies are def allies.

So is a turret defense against 2 troops in PS and SS? The only time it makes a difference what types of military one has is in specialty attacks?

51 troops attacking 50 turrets (with 0 troops and tanks) in PS would be a victory for the attacker?

51 troops with ps would break 50 turrets

troops 1 att/def
jet 2 att
turret 2 def
tank 4 att/def

in special attacks its troops vs troops and jets vs turrets and tanks vs tanks.

Sorry, I don't follow how 75 troops would break 50 turrets.

How does the game determine how many units are lost by each side? (negate tech, please)

exact formula isn't known.

Erring on the side of more as opposed to less, I found through my own short experiment that it's roughly 10% to 11% of the forces used for the offense. Sound close?

yea it varies around 10%, sometimes its more (~15%) sometimes its less (way under 10%). medical tech makes it even more random.