How can I fairly compare a socketed and unsocketed weapon?

Occasionally I'll happen across a new weapon with a socket but "worse" stats than my current, ruby-socketed weapon. How can I compare the two fairly without giving Shen my money?

(This example is probably too easy because the attack speeds are equal...)

Rubies add a flat amount of damage to weapons.

So take the average damage of the weapon, add the bonus for whatever Ruby you're looking to compare it to (11 in this example), then multiply by the attacks per second. Voila! Now you can compare the two weapons equally!

((WeaponMin + Weapon Max) / 2)  + RubyBonus = Average Damage
Average Damage * AttacksPerSecond = DPS

The math gets a great deal more calculated if your weapon has your class' primary stat on it. In that case, I'd suggest paying Covetous Shen - gold is easy to earn, after all.