Entropy Gain for per-receptor NPS

[RenegadeLucien]

Re: Entropy Gain for per-receptor NPS

Yeah I think we're talking about totally different concepts here. Per-receptor spikiness isn't something I ever really considered in my algorithm, at least not beyond "this note is really close to the last note for this receptor, therefore it should have a high value".

I can't think of any files off the top of my head where per-receptor spikiness plays a major factor in the difficulty of the file, so I can't judge how well the simple "this note is close" factor covers it. I do think such a metric would be valuable to have.

[xXOpkillerXx]

Re: Entropy Gain for per-receptor NPS

Yeah I think we're talking about totally different concepts here. Per-receptor spikiness isn't something I ever really considered in my algorithm, at least not beyond "this note is really close to the last note for this receptor, therefore it should have a high value".

I can't think of any files off the top of my head where per-receptor spikiness plays a major factor in the difficulty of the file, so I can't judge how well the simple "this note is close" factor covers it. I do think such a metric would be valuable to have.

Think Crowdpleaser, Death Piano ending, RAN's trilly bursts section or even party4u v1's 0-framers for more intense examples. Any jacks (per-receptor) faster than their surrounding notes basically. If you take total nps only, Death Piano's ending roll and trill are the same difficulty but obviously it's not the case. Per-receptor nps will clearly make the difference and rate the trill much higher than the roll.

[xXOpkillerXx]

Re: Entropy Gain for per-receptor NPS

Here's something I am wondering about per-hand stuff.

Is it safe to assume that any section with a high nps (x) on {3} and a lower nps on {4} is Harder than having x nps on both {3} and {4} ? Any counterexample is welcome.

More visually, I'm thinking that [34]4[34]4 is always harder than [34][34][34][34]. But only per-hand, so the same wouldn't apply with combinations of receptors like {2} and {3}, or {2} and {4}, etc. And by always I mean no matter what is before it, after it, and what's going on on the other receptors.

EDIT:
I will even go as far as claiming that if x is the nps on {3} and y is the nps on {4}, the peak of that per-hand difficulty is reached when x = 2y or 2x = y. When you lower small nps, you get things like [34]44[34]44[34]44, and when you raise it, you get [34][34]4[34][34]4, both of which I would argue are objectively easier than [34]4[34]4[34]4.

[RenegadeLucien]

Re: Entropy Gain for per-receptor NPS

If you take total nps only, Death Piano's ending roll and trill are the same difficulty but obviously it's not the case. Per-receptor nps will clearly make the difference and rate the trill much higher than the roll.

I wasn't talking about per-receptor NPS. Of course that is important, and my algorithm already covers it since it measures the distance between notes on the same receptor (in fact, in its current state, it freaks out at the DP megatrill and rates it higher than Undici). I was talking about the per-receptor spikiness that you had been describing in your last few posts. I don't know if there are any files where per-receptor spikiness add any difficulty that isn't accounted for by per-receptor NPS or distance between two notes on the same receptor.

Is it safe to assume that any section with a high nps (x) on {3} and a lower nps on {4} is Harder than having x nps on both {3} and {4} ? Any counterexample is welcome.

Mostly, as long as the nps on 4 is high enough. I don't really think, say, a long 3 jack with one random {34} jump (ex. AIM Anthem) in the middle is harder than a long {34} jack.

[xXOpkillerXx]

Re: Entropy Gain for per-receptor NPS

I wasn't talking about per-receptor NPS. Of course that is important, and my algorithm already covers it since it measures the distance between notes on the same receptor (in fact, in its current state, it freaks out at the DP megatrill and rates it higher than Undici). I was talking about the per-receptor spikiness that you had been describing in your last few posts. I don't know if there are any files where per-receptor spikiness add any difficulty that isn't accounted for by per-receptor NPS or distance between two notes on the same receptor.



Mostly, as long as the nps on 4 is high enough. I don't really think, say, a long 3 jack with one random {34} jump (ex. AIM Anthem) in the middle is harder than a long {34} jack.

Ok I get what you mean with that first paragraph. Indeed, there might not be a need for anything more than nps for per-receptor metrics. I will try to find any example where it would matter but on top of my head I dont see any either.

How high does your algo rate DP compared to Undici ? Those are really hard files and none have been AAA'd yet Right now, they're only 2 points apart from each other, and I would Not consider the opposite to be an error because it's only a single file (it's better to look at results as a whole first and then understand the difference between particular files, so not having your complete results, I can only assume things).

As for you AIM example, it would make no sense to put a long jack and a long jack with 1 jump in it at the same exact difficulty on a real numbers scale. The one with the jump Has to be harder, even if it's by a very small amount.

[leonid]

Re: Entropy Gain for per-receptor NPS

Does it also address the fact that difficulty differs based on what your goal is? Charts can be trivial to AA but impossible to AAA, or there's some stupid minefield that makes it really hard to pass but once you survive it's a guaranteed AA, etc

[xXOpkillerXx]

Re: Entropy Gain for per-receptor NPS

Does it also address the fact that difficulty differs based on what your goal is? Charts can be trivial to AA but impossible to AAA, or there's some stupid minefield that makes it really hard to pass but once you survive it's a guaranteed AA, etc

Right now I'm focusing solely on FFR. Since we use AAA equivalency, most of the difficulty will come from max values and length/stamina factors.

EDIT:
@leonid: stepmania is different obviously. What you describe as difficulty to AA, AAA, pass, are all very distinct values that may have a similar computing process but would have their own specific primitives. You can't possibly have a single metric for overall difficulty when your definition of difficulty is an undefined combination of 3 distinct aspects, otherwise you end up with obviously biaised results that are very hard to interpret. A fair comparison can be made with Etterna's calculator: if overall difficulty is some aggregate (like avg or weighted avg) of the per-pattern difficulties (jack, stream, js, etc), then it's not a surprise that they haveso many files to ban from leaderboards.

[RenegadeLucien]

Re: Entropy Gain for per-receptor NPS

How high does your algo rate DP compared to Undici ? Those are really hard files and none have been AAA'd yet Right now, they're only 2 points apart from each other, and I would Not consider the opposite to be an error because it's only a single file (it's better to look at results as a whole first and then understand the difference between particular files, so not having your complete results, I can only assume things).

Way higher. I haven't scaled it to match the 1-120 (or 1-99) FFR scale, but Undici is given a value of 49.5 (for some comparisons, RATO is 46.4, Magical 8bit Tour is 41.2, La Camp is 39.4). DP is given 62.7.

As for you AIM example, it would make no sense to put a long jack and a long jack with 1 jump in it at the same exact difficulty on a real numbers scale. The one with the jump Has to be harder, even if it's by a very small amount.

Yes, the 3 jack with the one 4 jump is harder than a 3 jack. But I question it being harder than a {34} jack. I don't know about you, but I can do faster 3 jacks than I can do {34} jacks.

[xXOpkillerXx]

Re: Entropy Gain for per-receptor NPS

Way higher. I haven't scaled it to match the 1-120 (or 1-99) FFR scale, but Undici is given a value of 49.5 (for some comparisons, RATO is 46.4, Magical 8bit Tour is 41.2, La Camp is 39.4). DP is given 62.7.



Yes, the 3 jack with the one 4 jump is harder than a 3 jack. But I question it being harder than a {34} jack. I don't know about you, but I can do faster 3 jacks than I can do {34} jacks.

Ok yes that is an odd result haha.

As for the jacks, the difficulty of perhand would be symmetric on both sides of of the 2:1 ratio, but the nps primitive would naturally make a [34] jumpjack harder than a 3 jack with a single [34] in it.

[blanky!]

Re: Entropy Gain for per-receptor NPS

I don't like difficulty being "one value".
It should vary in magnitude throughout the song, and be different kinds of difficulty.

Like, how do scores change if you're only slightly less good at hitting something than another player. Difficulty might not be that well, but if it means the difference between AAA'ing and good-rushing a difficult jumpstream, then the scores are highly sensitive to skill. Maybe that's a good measure? Change in score vs. change in skill in a certain direction? Dunno. Thoughts aren't fleshed out at all. Just food for thought.

[RenegadeLucien]

Re: Entropy Gain for per-receptor NPS

Like, how do scores change if you're only slightly less good at hitting something than another player. Difficulty might not be that well, but if it means the difference between AAA'ing and good-rushing a difficult jumpstream, then the scores are highly sensitive to skill. Maybe that's a good measure? Change in score vs. change in skill in a certain direction? Dunno. Thoughts aren't fleshed out at all. Just food for thought.

Thing is, for FFR specifically, this is a moot point because FFR difficulties are based strictly on the difficulty to AAA a song. It doesn't matter if a song is more prone to blackflags or 15g scores for people who are close to AAA'ing it, what matters is that the rating given to the song is higher then the rating that these players can AAA. Though I'd question that a player who consistently good-rushes a section of a song and ends up with 15g is close to AAA'ing it at all.

[xXOpkillerXx]

Re: Entropy Gain for per-receptor NPS

I don't like difficulty being "one value".
It should vary in magnitude throughout the song, and be different kinds of difficulty.

Like, how do scores change if you're only slightly less good at hitting something than another player. Difficulty might not be that well, but if it means the difference between AAA'ing and good-rushing a difficult jumpstream, then the scores are highly sensitive to skill. Maybe that's a good measure? Change in score vs. change in skill in a certain direction? Dunno. Thoughts aren't fleshed out at all. Just food for thought.

Could you elaborate on that bold part please ? I'm not sure I understand what you're asking for.

Also here's another idea, but I haven't found a way to make it fully non-trivial yet:
I can take the nps at every frame of a file (kinda like the nps generator), and figure out how long the file stays around its max nps. The only problem with that is I can't just put a random threshold like "time during which nps is at most 2nps away from max nps" or "time during which nps is higher than 95% of the max nps". Thoughts ?

[MinaciousGrace]

Re: Entropy Gain for per-receptor NPS

so did you get far enough to realize you have no idea what you're doing yet or did you just spout a bunch of bullshit and then do nothing

i swear you people that think everything can be solved with machine learning are worse than the people who think blockchain makes everything better

[xXOpkillerXx]

Re: Entropy Gain for per-receptor NPS

I didn't want to be pushy towards prawn because he seemed very busy already. I talked with him and for tests on the whole song db I need to ask him everytime. I have converted a few sm packs for basic tests but since those arent rated like ffr, I couldnt just accept/discard results (there also were some sketchy numbers with stuff like Beyond Bludgeonned, Big Black and Little piece of Heaven, stuff that extrapolation should still rate correctly). I still have formulas to try yet, but now I'm on vacation and not focusing on ffr at all. Will most likely get back to it when my semester starts (early september).

You seem to be in quite the hurry to see results for an arrogant ass. I think even if I manage to get good results I'll hide them from you.

[MinaciousGrace]

Re: Entropy Gain for per-receptor NPS

so basically you're in total denial still