Hi there!
I've tried to google some information about formulas of calculating melee hit chances and found out that there's no info.

I've started a new game with solo mod (Journey of the Lone Wolf). No glass cannon, hard difficulty, Source Difficulty mod. No restealth, but I use backstabs. Every fight is interesting cause I have to put alot of cc on enemies to prevent them freezing or stunning me and to avoid damage. I use full list of debuffing spells that I didnt use in previous games (when I got a tank) like curse, slow etc.
Now I got a lvl 6 rogue with some magic abilities (for cc, debuffs and buffs, no direct damage).
Stats: base: 5/15/9/5/7/5 with gear: 5/18/10/7/9/5
Attack rating 154, Defence rating 89

The problem is that even with 18 dex I get hit most of times in melee and by archers. In most turn-based RPGs like Neverwinter Nights when I maxed stats like dex I could evade many hits.
Is there a way to max dodge other than by putting more and more points in dex? What is the required defence rating for 50%/60%/70% dodging against most of enemies?
How much the chances change when there's a lvl difference between my character and enemies?

The best answer would be the calculation formula for attack/dodge chance, but every tip is welcomed ;)