Originally Posted by Darun
Originally Posted by DragonSnooz
It's 3.5 if you don't account for critical rolls, Natural 1's always missing and Natural 20's always hitting bring the value to +5.

Wrong. If you don't have a clue about a subject matter, don't try to lecture people who do. I admit I did not account for criticals, but that effect would be negligible, especially considering criticals will often deal overkill damage (Goblins).

Lol dude who's trying to lecture who? There's nothing wrong about the statement "it's 3.5 if you don't account for critical rolls", you don't even need Wolfram Alpha to see rolling two lone D20's approaches a value of 3.5. You can do it with two dice and scratch paper. I did that when I first go on the forum here, but instead of telling people, "You're wrong" I went to Google:
A Source
Other Sources

There's no reason to be crass because you used Wolfram Alpha. Some of us studied probability and statistics over a decade ago, but we don't flex on a forum community about it. (Because who cares, it's a forum). There already are more in-depth analysis on advantage online. Internet forums are full of anecdotes and often there was prior discussion before the anecdote became popular. Some even remember the story behind the anecdote better than I do. (Forums are great that way).

Originally Posted by dwig
The +5 comes from assuming a 50% chance to hit. That means that you miss on 0.5*0.5=0.25 (or 25% of the time) and you therefor hit 75% of the time. This is equivalent to +5.

Now, you would be correct in pointing out that this is the maximum benefit possible from advantage. It declines as you both raise and lower your chance to hit. It does overestimate the value of advantage a bit.

However, it is almost certainly a better estimate than assuming an even distribution of hit chances. In a well balanced game you will not see very many situations where you hit on a 2, or very many situations where you only hit on a 19 or 20. Given the actual to-hit chances that you will encounter in BG3 the value is probably between +4 and +5.

Sorry for not being perfect wink

Advantage being valued at +5 is an anecdote that has been used in good faith because a natural 20 can double the damage, always hit, etc. I'm glad that you're willing to admit that you did not account for critical rolls, but you can't consider double damage and a guaranteed hit negligible. During an entire campaign you will be fighting more than goblins. There are also other external factors to consider in Baldur's Gate 3 with mechanics such a shove, disadvantage on incoming attacks, enemies with lowered AC, etc. adding even more value to high ground. So is it just +3.5? It's a magnitude greater than 3.5.
Statisticians have to account for external factors, you cannot call it 3.5 and walk away.

I'd rather say it's about +5 than calculate values for each of those, I do have a day job and I've been playing Baldur's Gate 3 in my free time.