How do pokemon stats relate to attack power?

Question

The question: How do the stats of an individual pokemon relate to its abilities' damage?

For example: Let's say i have a pokemon that has 110 Atk and 100 Sp Atk. He knows 2 attacks: 1 is a Physical Attack with 80 power, and 1 is a Special Attack with 90 power. How do i determine which would deal more damage in the end?

Is the damage calculated by:

1. Adding the power to the stats (110 + 80 = 190, 100 + 90 = 190), meaning both attacks are equally powerful?
2. Are the powers a % based off of the stats (110 * 0.8 = 88, 100 * 0.9 = 90), meaning the special attack is better?
3. Some other way?

For the scope of the question, i would like to overlook things like damage boosting items, opponent's defense stats, STAB/Effectiveness, and other outside influences.

How does this work? And if too long, where can I read more about this?

Answer 1

Bulbapedia has the Pokemon damage formula. But the short answer is that it is multiplicative.

Which attack is better depends on your opponent's defenses, but lets assume they have 100 in both Defense and Special Defense. You didn't specify a level, so I'm going to assume 50. Results below with differences in bold.

For attack = (2*50 + 10)/250 * (110/100) * 80 + 2 = 40.72 * Modifier
For Special Attack = (2*50 + 10)/250 * (100/100) * 90 + 2 = 41.6 * Modifier

This shows your special move will be slightly stronger, which is expected for multiplicative factors (For any 2 numbers adding to the same sum, you will get the largest product when they have the least difference between them)

Note that pokemon has an element of randomness in the Modifier , and this can result in a 15% variance in practice.