Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Images altered to trick machine vision can influence humans too

deepmind.google

Post reply on HN
Print view View original

41–50 of 86 posts

Re: Images altered to trick machine vision can influence humans too

#41

Post by riwsky »

nyrikki wrote: post #23

"In our example, we may see a vase of flowers, but some activity in the brain informs us there’s a hint of cat about it." IMHO this is not the same as computer vision thinking a rolled over school bus is a snow plow. This is asking if someone sees an elephant or a unicorn in a cloud. Asking if a picture of a stop light at an intersection is "cat like" seems to be pretty suspectable to over fitting. Rorschach inkblot…

This is different because you’re not asking if one picture is feline, you’re asking which of two (basically identical) pictures is more feline; you would expect the pareidolia to be just as strong for each version.

Re: Images altered to trick machine vision can influence humans too

#42

Post by jaschasd »

_ogrr wrote: post #15

In case you were wondering what N was, their first experiment involved 16 undergrads psych students and the second experiment involved 12. https://link.springer.com/article/10.3758/BF03206939 Edit: I believe this linked survey is not the subject of the OP.

This comment is incorrect.

For experiments 1 through 4, N was 38, 389, 396, and 389. The subjects were not undergrad psych students.

The article linked in the parent comment does not correspond to any experiment in the blog post or the Nature Comms paper.

Re: Images altered to trick machine vision can influence humans too

#43

Post by [deleted] »

smeej wrote: post #31
_ogrr wrote: post #15

In case you were wondering what N was, their first experiment involved 16 undergrads psych students and the second experiment involved 12. https://link.springer.com/article/10.3758/BF03206939 Edit: I believe this linked survey is not the subject of the OP.

So when they say "more than half the time," they could very well be 9 and 7 people? No wonder they didn't cite the actual numbers in this summary write-up.

[deleted]

Re: Images altered to trick machine vision can influence humans too

#44

Post by riwsky »

glitchc wrote: post #11

This is a poor bit of research. The question "is it more cat-like?" Is leading as it specifically instructs the participant to look for cat-like features. The experimenters neglect to establish the null hypothesis.

The null hypothesis is that the participants are just as able to find those cat-like features in either perturbation of the image, and would pick the “right” one only 50% of the time.

Re: Images altered to trick machine vision can influence humans too

#46

Post by riwsky »

RandomLensman wrote: post #30
hervature wrote: post #28

Earlier quoted context omitted.

I think you misunderstand the experiment. They take an image of the flower, they perturb it so that the neural network classifies it as a "cat". They take another copy, perturb it so that the neural network classifies it as a "truck". They ask the subjects which one is more cat-like. A coin will choose the correct image 50% of the time. Likewise, a human that is not influenced by the pertubations will also pick corre…

Not clear if they had asked for "butterfly" instead of "cat" if 50/50 would have been the result. Similarly, if random perturbations influence choice, the baseline should include the noise from that.

The null hypothesis is 50/50 for butterfly, as well. From our conscious perception, it’s two copies of the same picture of a vase.

Re: Images altered to trick machine vision can influence humans too

#47

Post by jaschasd »

pain2022 wrote: post #17

> If brain activations are insensitive to subtle adversarial attacks, we would expect people to choose each picture 50% of the time on average. However, we found that the choice rate—which we refer to as the perceptual bias—was reliably above chance for a wide variety of perturbed picture pairs Ok, but the article doesn’t say what was the actual rate?

It does! See the effect strength plot near the bottom of the blog post, or Figures 2b and 3d in the paper.

The effect strength on humans ranges from a few percent deviation of human judgements from chance for subtle adversarial perturbations (epsilon=2), to ~15% deviations of human judgement from chance for large magnitude perturbations in the largest magnitude experimental condition.

Re: Images altered to trick machine vision can influence humans too

#48

Post by pbhjpbhj »

Caption on the first image :

>when perturbed by a seemingly random pattern across the entire picture (middle), with the intensity magnified for illustrative purposes

I don't understand? The pattern is not "seemingly random", it is "seemingly chosen to have subtle cat-features". One sees the ears at the top of them image and face-like features below.

So, is it "we perturbed images to overlay cat-like features on a visual level that humans don't generally perceive but ML models were able to perceive; and then ML models perceived them"?

Can someone précis the results and why they're interesting because on the face of it this seems like a very obvious outcome?

Do I need to make a new year resolution to actually read the articles?

Re: Images altered to trick machine vision can influence humans too

#49

Post by krisoft »

ShamelessC wrote: post #19
_ogrr wrote: post #15

In case you were wondering what N was, their first experiment involved 16 undergrads psych students and the second experiment involved 12. https://link.springer.com/article/10.3758/BF03206939 Edit: I believe this linked survey is not the subject of the OP.

Am I the only one who finds this to be a sort of wasteful experiment for one of the supposed top research labs in the country to be publishing in such a (supposedly) prestigious journal? The findings aren't super shocking although they would be interesting enough if they had managed to collect a large enough sample. Instead they barely grasp at straws and come to an obviously inflated conclusion that neural nets and…

> findings aren't super shocking

Aren’t they? Are you sure you understand what is the finding?

> they would be interesting enough if they had managed to collect a large enough sample

They did. The grand parent comment failed to read the right paper.

> obviously inflated conclusion that neural nets and human brains are similar in some way

But that is what they find. The human looks at two almost identical looking images of flowers. And yet when they are asked which one is more cat like they pick the one which the neural network thinks is cat-like too.(Or at least they pick it more often than if they were just selecting randomly in this seemingly nonsense task.) That is exactly “similar in some way”. Similar in which image they find more cat-like. That is the similarity.

Re: Images altered to trick machine vision can influence humans too

#50

Post by refulgentis »

pbhjpbhj wrote: post #48

Caption on the first image : >when perturbed by a seemingly random pattern across the entire picture (middle), with the intensity magnified for illustrative purposes I don't understand? The pattern is not "seemingly random", it is "seemingly chosen to have subtle cat-features". One sees the ears at the top of them image and face-like features below. So, is it "we perturbed images to overlay cat-like features on a vis…

You're not wrong, but this is interesting insomuch as it's it's more from 100% bug on the bug-feature axis to...well, wetware has this bug too it's just subconcious.
Post reply on HN