Black Raven Dragoons

[Grimblast]

Big edit to this post. The old forums for SWTOR had been wiped so the information I linked was lost. So, here's a nice alternative with even more added info on the secondary stats I'm sure some of us were trying to figure out.

I found the following information from Swtorhub.com that lays out what stats do as well as what classes have them as their primary stats.

Here's a summary of the information on their site.

Primary Stats
Strength

• Primary Stat for Jedi Knight/Sith Warrior
• Increases melee damage and critical strike chance.
• Class Bonus: Force Damage and Force Critical.

Presence

• Increases the effectiveness of your companion including, their health, damage, and healing.

Aim

• Primary Stat for Bounty Hunter/ Trooper
• Increases damage and critical chance with ranged weapons.
• Class Bonus: All advanced classes receive a bonus to tech damage and critical while Commando/Mercenary also gain a bonus to healing power.

Cunning

• Primary Stat for Smuggler/ Imperial Agent
• Increases your tech damage and critical chance.
• Class Bonus: All advanced classes receive a bonus to tech damage and critical while Scoundrel/ Operative also gain a bonus to healing power.

Endurance

• Increases your maximum health and health regeneration.

Willpower

• Primary Stat for Jedi Consular/ Sith Inquisitor
• Increases your damage and critical chance with force abilities.
• Class Bonus: Shadow/ Assassin gain melee damage and critical bonus. Sage/Sorcerer receive an increase in healing power.

Expertise

• Increases your effectiveness in PVP combat by reducing damage taken and increasing damage dealt when facing another player.

Secondary Stats
Accuracy Rating

• Increases the chance that any of your attacks will hit the target. Any accuracy over 100 percent will reduce the targets defense.

Power

• Provides an increase in damage and healing for all abilities. There are also Tech, Force, and Healing specific power stats available on certain gear and modifications.

Alacrity

• Decreases the activation time for all of your abilities both cast and channeled.

Surge

• Increases the percentage of damage dealt and amount healed during a critical.

Critical Rating

• Increases the chance of a critical attack or heal.

Defense Stats
Armor

• Reduces the amount of damage received from kinetic and energy based attacks.

Damage Reduction

• The four types of damage reduction in the game are kinetic, energy, internal, and elemental. While all four can be increased by finding gear with those specific reductions, kinetic and energy are also bolstered by your armor rating.

Shield Chance

• Any classes that are able to equip an off-hand shield will see this stat which represents the chance of that shield activating. You will also find an absorption rating, which depending on the shield, is how much damage it will take when activated.

Defense Chance

• Increases your chance to avoid attacks all together. It’s broken down into four categories including melee parry, ranged deflect, force resistance, and tech resistance.

Additional Info/Math
I found the following information on starwarsmmolevelingguide.com.

All primary stats give 1% crit for every 140 (at level 50)
Aim gives 0.2 ranged damage
Strength gives 0.2 melee damage
Cunning gives 0.2 tech damage
Will power gives 0.2 force damage

Assuming I understood the information correctly, for every 1 point of Aim, Strength, Cunning, and Will power, they boost respective damage by 0.2.

Hopefully all this posted information helps. As always, my sticky posts are works in progress and I try to make sure I post my sources. Sometimes the linked information changes so I still recommend following the links and checking those when you have time.