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Comment by tidenly | Hacker News Reader

Your point doesnt refute OPs argument. Your final statement "you can say the latter is more likely random" is not the same as "you can say this sequence is not random". I think lots of people (especially programmers) who know about true RNG vs expectations of RNG might intentionally put in strings of same numbers, or not include the full set, because we know its what often happens during plain RNG. It isnt clear what the goal of the sequence is, hence the confusion in the comments.

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Exactly, and their "good" dice roll sequence, 3 1 5 6 2 6 3 4 4 1 contained the full set which should only happen ~1/4 of the time for 10 rolls. It also contained no number more than twice, which should happen < 7% of the time. This looks to me like they purposely tried to make this sequence look like their idea of "random".

I'm curious about how they scored this section because my overall age was reported to be 60+ with the sequence 2 1 5 2 6 2 2 4 6 6.

I also scored 60+ (actual age is in my 30s). I had similar thoughts and also did things like not use up all the numbers and repeat numbers more than twice exactly because I've looked at a lot of random number sequences in my life and I was trying to make it look like one of those.

> I've looked at a lot of random number sequences in my life and I was trying to make it look like one of those.

This is perhaps the difference between pseudo and statistically random. No idea which of those the study or the experiment is trying to validate btw.

And IIRC, interestingly they write that human capacity to create random numbers declines 25+. I can imagine that the older we are the more we look for something to make our decisions look more random based on what we've learned so far - more time, there was more time to look at more random number sequences - and the less random the outcome will be.

> And IIRC, interestingly they write that human capacity to create random numbers declines 25+. I can imagine that the older we are the more we look for something to make our decisions look more random based on what we've learned so far - more time, there was more time to look at more random number sequences - and the less random the outcome will be.

This is what they are testing, and at least based on the data they've got so far, it looks like it increases up to 25-ish and then stays pretty flat.

Another possibly interesting observation is that their preliminary data set (just eyeballing it, but) looks to have gotten

1) a flatter response

2) generally, less random responses

Which leads me to wonder if the live stats have been skewed more random as there might be some correlation between "interested in this sort of thing" and "has some idea what a random distribution ought to look like," and possibly this knowledge doesn't go away with age.

> This is what they are testing

(human capacity to create random numbers declines 25+)

Not really; what they're testing is what kinds of response differently-aged people give to their question. So it's important what the question actually is; and it's important if the question might, for example, seem to older people to be a waste of their time.

They're not measuring what they claim to be measuring.

My opinion is that "real" randomness looks less random than artificial randomness.

That's why Apple changed iTunes random music shuffle to be less random because people complained that it wasn't random enough and replayed songs too close together.

https://www.cultofmac.com/181517/why-itunes-shuffling-order-...

> This is perhaps the difference between pseudo and statistically random.

Not quite. Pseudo-randomness is defined as being indistinguishable from a uniform distribution, meaning if the next in a sequence is no more predictable than a statistically random selection.

1/4 of the time and <7% does not make it impossible. In fact thats kinda the whole point of RNG.

I always pressed the same button. Let's say 10x 1. You get a rating below 60 then. Just in case you need the sequence to come towards your real age group when you redo the experiment.

Perhaps to guess random is also in the property of the age of someone clicking on a website? Perhaps someone should create an experiment that finds their experiment flawed ^^

What does that mean, "you can tell this sequence is not random"? If you show me a blue hat, and ask me if it's blue, I'll say yes, I can say it's blue. But there is always a chance it's not actually blue. It's very conceivable that I'm in a situation where I say with confidence that something is blue, but it isn't.

You always only ever speak in probability. Of course you can't say the sequence isn't random, because every sequence can be the result of a random process. "can you tell which is random" to me is equivalent as asking "is one of the sequences such that it is rational to choose it over the other as being random".

It's about rational decisions. Consider the frequentist view, where a probability p for an event A means that out of k trials, pk will show A (in expectation), and fruthermore if k -> infty, then the portion of events that show A will converge to p. If you want to choose the right sequence as being random as often as possible, it is rational to choose the one I described above, because it will, overall, be the one that is MORE OFTEN the random one compared to the other.

For a blue hat, it either is or isn't blue (and there's some rather strong evidence - whether or not it looks blue). Like, with a sequence of 6 digits, if you don't know whether the source was random or not, then that's like NOT showing me your hat, and asking me whether it's red or blue.

For a single sequence of six digits, it might or might not have come from a random source. You can't get any edge on that judgement by just inspecting the sequence. Only inspecting the source (the hat, if you like) can give you an advantage. Perhaps you're colour-blind, or the lighting is weird; so there's still uncertainty. But that's equivalent to examining the source of the digits, determining that it's really a random source, but making a mistake in your determination. That's uncertainty on a different level.

Red-pill blue-pill is a sort of meta-uncertainty.

> "is one of the sequences such that it is rational to choose it over the other as being random"

Most people don't care about this shit; it doesn't matter to them what random means, nor whether it's sequences or sources that can be said to be random. But for some people it does matter, and they have to try to use language precisely.

All [red|blue] hats are either red or blue. But no sequence is random or non-random; it's the source of the sequence (the process, if you like) than can be random or non-random.

If 111111 is emitted by a random process, then you can call that a "random sequence" if you like. If I emit 126692 from my ass (not a random process), that's not a "random sequence" in any sense, whatever statistical properties it has. You can't tell which is of random origin by inspection. The experimental subjects face an impossible challenge, and I can't see what conclusions you can draw from their responses.

Regarding "random process": (and sorry for commenting to myself)

I'm not taking a position on what a "random process" is; for these purposes, a PRNG, a LFSR or even the last three bits of the system-clock would do as well as radioactive decay.

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