4 ms·

> The space of possible avatars (2^256, in this case) is far, far larger than the number of distinct objects that humans can distinguish between. That sounds i

by sva_ 6y ago

> The space of possible avatars (2^256, in this case) is far, far larger than the number of distinct objects that humans can distinguish between. That sounds intriguing to me. Are you aware of any research into this?

nemo1618 6y ago
To be honest, I have no idea how many distinct objects humans can distinguish between, but I am 99% confident that it is fewer than 2^128, much less 2^256. I suppose it's a somewhat nuanced question, though. For example, if I were shown every avatar in sequence, I'm quite sure I would always notice the "diff" between two consecutive avatars. But the bar that I have in mind is much, much higher: given a sequence of avatars, can I recognize my friend's avatar with 100% accuracy? Given that we can't even do this within the set of <8 billion human faces (we occasionally accost a stranger as though they were a friend), I have to conclude that doing so within a set of 2^256 abstract shapes is entirely hopeless.
- dwpdwpdwpdwpdwp 6y ago
  It is definitely a nuanced question. The definition of object is surely up for debate as well. A silly example: if one were to define an object as a string of 64 hex characters, even non-literate people could distinguish between any two distinct objects. echo "hello" | sha256sum >> 5891b5b522d5df086d0ff0b110fbd9d21bb4fc7163af34d08286a2e846f6be03 echo "world" | sha256sum >> e258d248fda94c63753607f7c4494ee0fcbe92f1a76bfdac795c9d84101eb317 But were I to briefly glance at a computer screen, I'd probably confuse these next two: e258d248fda94c63753607f7c4494ee0fcbe92f1a76bfdac795c9d84101eb317 e258d248fda94c63753607f7c4494ee0fcbe92f1a76bfaac795c9d84101eb317
- sva_ 6y ago
  Yeah, I should've been more clear. There's no doubt that humans can't distinguish/memorize 2^256 abstract shapes. However, only a small subset of those would have to be memorized - those which are relevant to the individual. I'd agree that this particular pattern doesn't have enough variability for each pattern to be unique enough to reliably identify it, but I'd conjecture that its possible to make such a pattern, which has enough variability and unique characteristics to be recognizable (ignoring the fact that an adversary could make a very similar pattern to mislead the individual - I'm not curious about it for verification.) Your example of the fact that we can't reliably recognize every face on this planet is very interesting. Let's imagine we know n faces which I can reliably distinguish from one another, but now there is a (n+1)th face which I mix up with one of the previous ones. Now lets assume this face would instead have a very unique characteristic, unlike all previous faces - lets imagine for example, the nose on this face is upside down. Surely I'd be able to differentiate it from the previous n faces, hence the issue of identifying it might've been the limited variability/characteristics in the various previous instantiations of a face. So there are a number of characteristics in a face, which have a certain degree of variability, which enable us to distinguish from a number of them. I've been pondering on how many of those characteristics could be combined in an object, and how high the variability could be; to create uniquely identifiable patterns. It probably depends a lot on the meaning we attribute to the pattern, different associations we have to it. I apologize - quite the tangent, I guess. I've just been pondering a lot on this for a project I've been working on for some time.
- deleted 6y ago
  [deleted]
- nemo1618 6y ago
  FOLLOW-UP: It occurs to me that, actually, plenty of humans could definitely clear my "higher bar." All you need to do is memorize a 64-character hex string, which is difficult but completely doable using a memory palace or similar technique. Practically speaking, though, this isn't something that the average person is capable of doing. Even memorizing one hex string, let alone multiple (for each of your friends), requires a lot of effort for little benefit. Furthermore -- if you can memorize the hex directly, you don't need the avatars in the first place! :P
  - stock_toaster 6y ago
    People memorize digits of pi. An outlier for sure, but a 7 year old memorized over 1k digits a few years ago. Pretty crazy!
HideousKojima 6y ago
https://www.researchgate.net/publication/236023905_Color_difference_Delta_E_-_A_survey https://www.researchgate.net/publication/236023905_Color_dif...
g_sch 6y ago
It's a simple order of magnitude calculation. 2^256 is greater than one billion to the eighth power, times 100,000. There are probably several possible ways you could estimate how many different objects a person could distinguish between, but I think it's unlikely you'd come up with even a single billion.
- littlestymaar 6y ago
  > but I think it's unlikely you'd come up with even a single billion. One billion is really really tiny though, let's just play a game : - Unless you're colorblind, you can easily tell ten hues apart. Let's pick two colors, one with a saturated hue, and the other with a pastel one. That's 100 possibilities. - I'm pretty sure you can easily recognize pictures of a hundred people you've met at some point in your life. Let's pick two of them, that's 10 thousand combinations. - can you recognize ten different road signs? Ten country shapes ? Ten animals ? Ten fictional character? Ten books cover? Ten celebrities? Just pick three categories, and you've got a thousand combinations. Now I'm pretty sure you can tell your grandma sitting under a vivid pink UK shape next to your 9th grade math teacher staring at Bruce Willis holding a giant light blue stop sign apart from any other imaginable combinations. An untrained[1] human brain probably cannot distinguish between 2^256 items, but it's still able to do it for massive numbers. [1]: but maybe it's possible with training: for instance, chess professionals might be able to do it.

by sva_ 6y ago

nemo1618 6y ago

To be honest, I have no idea how many distinct objects humans can distinguish between, but I am 99% confident that it is fewer than 2^128, much less 2^256. I suppose it's a somewhat nuanced question, though. For example, if I were shown every avatar in sequence, I'm quite sure I would always notice the "diff" between two consecutive avatars. But the bar that I have in mind is much, much higher: given a sequence of avatars, can I recognize my friend's avatar with 100% accuracy? Given that we can't even do this within the set of <8 billion human faces (we occasionally accost a stranger as though they were a friend), I have to conclude that doing so within a set of 2^256 abstract shapes is entirely hopeless.

dwpdwpdwpdwpdwp 6y ago
It is definitely a nuanced question. The definition of object is surely up for debate as well. A silly example: if one were to define an object as a string of 64 hex characters, even non-literate people could distinguish between any two distinct objects. echo "hello" | sha256sum >> 5891b5b522d5df086d0ff0b110fbd9d21bb4fc7163af34d08286a2e846f6be03 echo "world" | sha256sum >> e258d248fda94c63753607f7c4494ee0fcbe92f1a76bfdac795c9d84101eb317 But were I to briefly glance at a computer screen, I'd probably confuse these next two: e258d248fda94c63753607f7c4494ee0fcbe92f1a76bfdac795c9d84101eb317 e258d248fda94c63753607f7c4494ee0fcbe92f1a76bfaac795c9d84101eb317
sva_ 6y ago
Yeah, I should've been more clear. There's no doubt that humans can't distinguish/memorize 2^256 abstract shapes. However, only a small subset of those would have to be memorized - those which are relevant to the individual. I'd agree that this particular pattern doesn't have enough variability for each pattern to be unique enough to reliably identify it, but I'd conjecture that its possible to make such a pattern, which has enough variability and unique characteristics to be recognizable (ignoring the fact that an adversary could make a very similar pattern to mislead the individual - I'm not curious about it for verification.) Your example of the fact that we can't reliably recognize every face on this planet is very interesting. Let's imagine we know n faces which I can reliably distinguish from one another, but now there is a (n+1)th face which I mix up with one of the previous ones. Now lets assume this face would instead have a very unique characteristic, unlike all previous faces - lets imagine for example, the nose on this face is upside down. Surely I'd be able to differentiate it from the previous n faces, hence the issue of identifying it might've been the limited variability/characteristics in the various previous instantiations of a face. So there are a number of characteristics in a face, which have a certain degree of variability, which enable us to distinguish from a number of them. I've been pondering on how many of those characteristics could be combined in an object, and how high the variability could be; to create uniquely identifiable patterns. It probably depends a lot on the meaning we attribute to the pattern, different associations we have to it. I apologize - quite the tangent, I guess. I've just been pondering a lot on this for a project I've been working on for some time.
deleted 6y ago
[deleted]
nemo1618 6y ago
FOLLOW-UP: It occurs to me that, actually, plenty of humans could definitely clear my "higher bar." All you need to do is memorize a 64-character hex string, which is difficult but completely doable using a memory palace or similar technique. Practically speaking, though, this isn't something that the average person is capable of doing. Even memorizing one hex string, let alone multiple (for each of your friends), requires a lot of effort for little benefit. Furthermore -- if you can memorize the hex directly, you don't need the avatars in the first place! :P
- stock_toaster 6y ago
  People memorize digits of pi. An outlier for sure, but a 7 year old memorized over 1k digits a few years ago. Pretty crazy!

HideousKojima 6y ago

https://www.researchgate.net/publication/236023905_Color_difference_Delta_E_-_A_survey https://www.researchgate.net/publication/236023905_Color_dif...

g_sch 6y ago

It's a simple order of magnitude calculation. 2^256 is greater than one billion to the eighth power, times 100,000. There are probably several possible ways you could estimate how many different objects a person could distinguish between, but I think it's unlikely you'd come up with even a single billion.

littlestymaar 6y ago
> but I think it's unlikely you'd come up with even a single billion. One billion is really really tiny though, let's just play a game : - Unless you're colorblind, you can easily tell ten hues apart. Let's pick two colors, one with a saturated hue, and the other with a pastel one. That's 100 possibilities. - I'm pretty sure you can easily recognize pictures of a hundred people you've met at some point in your life. Let's pick two of them, that's 10 thousand combinations. - can you recognize ten different road signs? Ten country shapes ? Ten animals ? Ten fictional character? Ten books cover? Ten celebrities? Just pick three categories, and you've got a thousand combinations. Now I'm pretty sure you can tell your grandma sitting under a vivid pink UK shape next to your 9th grade math teacher staring at Bruce Willis holding a giant light blue stop sign apart from any other imaginable combinations. An untrained[1] human brain probably cannot distinguish between 2^256 items, but it's still able to do it for massive numbers. [1]: but maybe it's possible with training: for instance, chess professionals might be able to do it.