How does the base Defense stat get calculated for PC/NPCs?

[Mellowtron11 180]

Basically, how do your player character and party members get their final base Defense stat at low levels? I know there's a few things that add to it, like the modifiers from your dexterity stat (e.g. 14 DEX has a +2 modifier) and feats like Jedi Sense and Scoundrel's Luck add to defense over time. However, most of your party still have high defense scores even at low levels like 3 or 6, as seen below. 

 

http://www.gamebanshee.com/starwarskotorii/npcs/handmaiden.php

 

http://www.gamebanshee.com/starwarskotorii/npcs/attonrand.php

 

I know that 3.5 D&D had a formula for this stat:

 

10+armor bonus+ shield bonus+ dexterity modifier+ size modifier

 

http://www.dandwiki.com/wiki/SRD:Armor_Class

 

I know there are a few differences (no size modifier or shield bonus in KOTOR1/2), but is that pretty much how defense was calculated in both games? Were other modifiers added to the final defense stat, aside from the starting number of 10 and the dex. modifier?

[bead-v 251]

DEF = 10 + Natural AC [1] + Class AC (acbonus.2da) [2] + DEX [3] + (PlayerLevel * armormult(autobalance.2da) +2) _{(only if mult > 0)}

 

http://deadlystream.com/forum/topic/5540-character-stat-guide/