How good is Advantage in D&D?

Can we equate rolling with advantage in Dungeons and Dragons to a flat modifier? Let's ask this kenku we pulled off the street. Oh no, they're going on a long-winded tangent on probability...

(Note for commenters: I am aware that rolling a 1 is automatically a failure for attack rolls; however in 5th edition fail-on-1 for ability checks and saving throws is an optional rule, not an official one.)

0:00 Modifiers vs advantage
2:05 Equating advantage to a flat modifier
4:51 Other questions about interpreting probabilities
6:42 Odds as a way of comparing probabilities
9:06 Conclusions

[altejoh]

I think its also worth mentioning that, in 5e, anything above a +1 or +2 modifier is a *significant* improvement from what you would get normally. So "only" getting effectively +3 or +4 is still pretty huge. Additionally, there is never any downside to advantage, so you should always be trying to seek it - which (in theory) leads to more interaction with the environment and creative solutions to problems.

[jumperpro]

My favorite quote from my time playing pokemon is "if it isn't 100% accurate its 50% accurate" this comes from focus blast seeming to miss more times then it hits.

[PainMaker]

One thing you’re forgetting is that advantage nearly eliminates a critical miss, while disadvantage nearly eliminates critical hits. To get either, you need to roll both 1s or both 20s, respectively. When compared with the likelihood of rolling any other combination of rolls, the odds of rolling a critical miss or critical hit are 1 in 400.

[fluffyllama]

I've taken master's level statistics classes and this is the first time "odds" vs "probability" made sense to me

[cameronmahler]

There is one case that I know of where the rules of 5e DO convert the advantage/disadvantage system to a direct modifier. That is with passive scores: "If the character has advantage on the check, add 5. For disadvantage, subtract 5" (Player's Handbook p. 175)

[edoardocaccia]

The mention to Pokémon when you brought up the perspective of looking into thw chance to fail is spot on. A 95% accuracy move is only slightly worse than a 100% one but the same 5% drop from 90% to 85% feels like a ravine

[YanYanicantbelievethistakenffs]

How to lie with statistics.
A classic.
All the numbers mean the same but our perception is what is changing.
10/10 explanation i loved to revisit this topic.

[vorquel]

"or you can just not over-engineer your character like an absolute nerd"
Sir, you are talking about TTRPG players. We are all nerds here.

[c]

Another fun one comes from the RPG realm outside of D&D. Some games, like the "kids on bikes" system, use "exploding dice", where if you roll the maximum of an n-sided die, you get to roll again and sum the results, and this can repeat.

This has a number of fun effects: on a D4, it's impossible to roll any multiple of 4. Exploding with a D4 _twice_ is more likely than exploding once with a D20. The probability of getting any given number is never 0, as the exploding has the potential to go on forever.

[NinjaOfLU]

I love how the Kenku must have put time and effort into getting people to say all the things like 'Taylor expansion' to make this rant.

[josephnewton]

I had to do a sneaky re-upload to fix an error, so apologies if your comment or like got overwritten or if you got double notifications. Feel free to re-comment or re-like!

[lake]

07:52 this felt like that moment when you're looking at your math book for too long and look up to see what the teacher has drawn on the board.

[VladimirE.-isee]

The graph at 8:02 is exactly why I Iike advantage (as a long term 3.5 player to boot), simply because it accurately models the actual 'advantage''s meaning. Like, say you're shooting at someone who has been webbed. Even a lousy shot is going to have an easier time shooting at a target that doesn't move, but for an experienced shot, it makes it go from 'this will go well, trust me' to 'I can do it with both hands up my arse'. Which makes advantage a very apt go-to tool for resolving unknown situations.

[Maltiez]

There is a Stand-up Maths video on this topic, called The unexpected logic behind rolling multiple dice and picking the highest.

[musiclistener]

Lol I sent this to a friend saying "first time ever I've seen someone be comprehensive on each of these angles and he does it in under 10 minutes" then GASPED when youtube recommended me "more from..." and I realized you were the cursed units guy.

This is another amazing vid.

[mmefett]

Wow, this is so well made. You explained how the different probability conversations worked so intuitively that anyone could understand

[patrickburke]

I appreciate this video because I’ve never heard anyone else complain about the phrase “twice as likely” but I’ve always hated when people say that, this made me feel less insane

[negativerainbow]

My immediate reaction to this information is "let's just use both depending on the situation", but I just like having lots of knobs to tweak.

[Nickname]

An Xcom player wouldn't be able to explain the difference between 5% and 99% propability of success, they might aswell be the same probabliity.

[elbruces]

The ratio of how informative this video is to how much I learned from it, is off the charts.