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Opinion: Artificial Intelligence Hits the Barrier of Meaning (nytimes.com)

Machine learning algorithms don't yet understand things the way humans do -- with sometimes disastrous consequences. Melanie Mitchell, a professor of Computer Science at Portland State University, writes: As someone who has worked in A.I. for decades, I've witnessed the failure of similar predictions of imminent human-level A.I., and I'm certain these latest forecasts will fall short as well. The challenge of creating humanlike intelligence in machines remains greatly underestimated. Today's A.I. systems sorely lack the essence of human intelligence: understanding the situations we experience, being able to grasp their meaning. The mathematician and philosopher Gian-Carlo Rota famously asked, "I wonder whether or when A.I. will ever crash the barrier of meaning." To me, this is still the most important question.

The lack of humanlike understanding in machines is underscored by recent cracks that have appeared in the foundations of modern A.I. While today's programs are much more impressive than the systems we had 20 or 30 years ago, a series of research studies have shown that deep-learning systems can be unreliable in decidedly unhumanlike ways. I'll give a few examples. "The bareheaded man needed a hat" is transcribed by my phone's speech-recognition program as "The bear headed man needed a hat." Google Translate renders "I put the pig in the pen" into French as "Je mets le cochon dans le stylo" (mistranslating "pen" in the sense of a writing instrument). Programs that "read" documents and answer questions about them can easily be fooled into giving wrong answers when short, irrelevant snippets of text are appended to the document.

Similarly, programs that recognize faces and objects, lauded as a major triumph of deep learning, can fail dramatically when their input is modified even in modest ways by certain types of lighting, image filtering and other alterations that do not affect humans' recognition abilities in the slightest. One recent study showed that adding small amounts of "noise" to a face image can seriously harm the performance of state-of-the-art face-recognition programs. Another study, humorously called "The Elephant in the Room," showed that inserting a small image of an out-of-place object, such as an elephant, in the corner of a living-room image strangely caused deep-learning vision programs to suddenly misclassify other objects in the image.

11 of 217 comments (clear)

  1. So it's basically an old-school overtraining by Impy+the+Impiuos+Imp · · Score: 5, Interesting

    I wonder if these AI vision systems that input millions of images are actually doing a deep learning, or are just canvassing pretty much every image possibility such that any possible live image is just a tiny automated delta calculation away from an answer.

    This would explain why tweaking the input in the described ways would throw the AI into a tizzy -- the tweaked input isn't within a tiny delta of any of the millions of categorized images.

    --
    (-1: Post disagrees with my already-settled worldview) is not a valid mod option.
    1. Re:So it's basically an old-school overtraining by taustin · · Score: 5, Interesting

      There was a military experiment years ago trying to teach a computer to distinguish between friendly and enemy tanks. They showed it thousands of photos of each, and in the test bed, it was very, very accurate. When used under battlefield conditions, however, it went to hell in a handbasket.

      Turned out they hadn't taught it to distinguish between US and Russian tanks, they had taught it to distinguish between high quality photos (used for marketing meetings with Congresscritters for funding), and crappy, grainy Polaroids (which was all they had of the Russian tanks).

      They'll learn what you teach them, but what you teach them may not have anything to do with what you want them to learn.

    2. Re:So it's basically an old-school overtraining by dj245 · · Score: 4, Interesting

      There was a military experiment years ago trying to teach a computer to distinguish between friendly and enemy tanks. They showed it thousands of photos of each, and in the test bed, it was very, very accurate. When used under battlefield conditions, however, it went to hell in a handbasket.

      Turned out they hadn't taught it to distinguish between US and Russian tanks, they had taught it to distinguish between high quality photos (used for marketing meetings with Congresscritters for funding), and crappy, grainy Polaroids (which was all they had of the Russian tanks).

      They'll learn what you teach them, but what you teach them may not have anything to do with what you want them to learn.

      That's a great story and perfectly illustrates the pitfalls of machine learning. I (a mechanical engineer) took a data science class and the main takeaway I got was that machine learning basically fits a curve of predicted behavior based on input variables. The "training" dataset is what you feed it to figure out the curve. Then you test it on a different dataset to make sure it isn't bonkers. Removing or adding one input variable can dramatically change the influence strength or even the sign (+/-) of the other variables in the prediction formula that the process generates. If you have hundreds of input variables it becomes completely impossible for a human to understand all the relationships between the variables in the prediction function. So even if the machine learning software can generated a good predictive function, a human may not be able to understand how that predictive function works if few or none of the input variables are dominant.

      --
      Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
    3. Re:So it's basically an old-school overtraining by es330td · · Score: 3, Informative

      My youngest son is on the autism scale. One trait of some people with autism is that for them there is no such thing as a general case. A room with furniture does not have a "delta" wherein a moved chair is "previous room with a chair in a different place"; instead, every arrangement of the room is a different room. No number of different arrangements will ever coalesce into them being understood as variations on the same base room.

  2. Great! by Locke2005 · · Score: 3

    "...programs that recognize faces and objects, lauded as a major triumph of deep learning, can fail dramatically when their input is modified even in modest ways by certain types of lighting, image filtering and other alterations that do not affect humans' recognition abilities in the slightest." Now tell me again what a great idea self-driving cars are!

    --
    I've abandoned my search for truth; now I'm just looking for some useful delusions.
    1. Re:Great! by ganv · · Score: 3, Insightful

      Yes, that is what learning systems do. They continuously use new data to revise their responses, and most of the failures described in the post can be handled if they are included in the training data set. The great question is whether extracting 'meaning' is in some sense simply a deep learning system that is better trained and able to use additional layers to provide context or whether 'meaning' is some categorically new thing that current approaches to machine learning are fundamentally missing. I suspect that meaning is not something categorically new, but that the complexity of the integration of current input with learned processing in humans is not soon to be replicated. We'll probably create some other kinds of intelligence that can do many more things humans find unimaginable (similar to the way computers currently do computations) while still being unable to do many things that human toddlers do with ease.

    2. Re:Great! by Layzej · · Score: 3, Interesting

      The question (which the writer didn't ask or answer) is how the machine learning systems can be improved to be more resistant against such simple modifications.

      https://www.quantamagazine.org...

      When human beings see something unexpected, we do a double take. It’s a common phrase with real cognitive implications — and it explains why neural networks fail when scenes get weird.

      ...

      Most neural networks lack this ability to go backward. It’s a hard trait to engineer. One advantage of feed-forward networks is that they’re relatively straightforward to train — process an image through these six layers and get an answer. But if neural networks are to have license to do a double take, they’ll need a sophisticated understanding of when to draw on this new capacity (when to look twice) and when to plow ahead in a feed-forward way. Human brains switch between these different processes seamlessly; neural networks will need a new theoretical framework before they can do the same.

    3. Re:Great! by religionofpeas · · Score: 4, Insightful

      When human beings see something unexpected, we do a double take

      Of course, you first need to see something unexpected. In the famous video of white/black people passing a ball, very few people noticed the gorilla. They never did a double take. https://www.youtube.com/watch?... This happens all the time in real life.

  3. Finally, a comment on AI that I can support by TomGreenhaw · · Score: 4, Interesting

    The Turing test has led us down a rocky road and we have a very long way to go. Artificial human-like intelligence IMHO is still a long way away. Most people make shoot from the hip assumptions about how the brain works and after doing some basic math about Moore's law assume super intelligence is right around the corner.

    The brain is way more complicated than we know.

    For example: there are two stable isotopes of lithium. Chemically they are identical, but they do not have the same effect on the brain. One is useful as a drug to treat mental illness and the other is not. This means there is something more subtle about how our brain works than interconnections and electrochemistry.

    It is however a worthy challenge because the journey will teach us much about who we really are and how we work.

    --
    Greed is the root of all evil.
  4. Re:They say... by CanHasDIY · · Score: 3, Interesting

    Thanks for the link. I read the article and many of the comments.
    What do you think about this one?

    The same thing I think about anyone who claims that a major moment in human history boils down to 1 factor - it's bullshit, man.

    Yes, slavery was a factor, but not the only factor. Consider the tariffs I linked to, then ask yourself: under those trade rules, how would the Southern states have managed to survive without the use of slave labor? The fact is, they wouldn't have, so in a way the Northern states forced the South to rely on slavery, then punished those states for it.

    The fact is, our American Civil War was complicated, both the reasons for it's beginning and continuation (fun fact - Lincoln floated the idea of leaving slavery legal in some states, to preserve the union). What's interesting as an American is that the angle historians take on the conflict tends to be defined by where you get the education: Northern states tend to teach the "Civil War was about slavery" concept, Southern states lean towards the "state's rights" ideology, and Border states (like where I'm from) tend to take a more middle-of-the-road, "both of you are assholes" mentality.

    --
    An enigma, wrapped in a riddle, shrouded in bacon and cheese
  5. It's about compression. Everything in fact is. by goombah99 · · Score: 3, Interesting

    Entropy. Compression. Same thing. The whole world is thermodynamics and your state of knowledge about the world is also limited by thermodynamics. There will never be a computer that can predict the future of the universe before the universe arrives simply because you can't store a representation of the universe inside the universe itself.

    Lossy Compression is therefore how we get around that and be able to compute/think/predict what an approximate future state of the universe is.

    What the goal is to align the losses of the compression into the input space which does not exist. For example, if there is no possibly image of a living room of size smaller than an elephant that could contain the elephant then any mapping of images with and without elephants to the same compressed reprensention is a good compression. To say it differently the compresses state is a many to one mapping back to the original state. If for every compressed state there is only one realizable original state then it's invertable. THe images in the original space that could never happen are also mapped to the same compressed state but because they could never exist we lose nothing by ignoring them.

    Thus compression and prediction are the same thing.

    AI fails when it either over-compresses to a space too small to hold every realizable state. Or it compresses poorly so that in unnessarily conflates two possible real states. For example, the uber car that thought the woman in the road was blowing trash.

    On the otherhand, it's often very valuable to overcompress as long as you are tolerant of mistakes on the prediction. That is, the uber car in question was able to do a great job of driving most of the time because it made fact choices that were nearly always good enough. The Cheetah can't just chase the antelope, it needs to try to guess and cut corners a bit. As long as most of it's guesses are good it wins. In the case of the cheetah, a mistake just means a missed meal, which is tolerable. But in the case of the uber driver or an ICBM nuclear missile failsafe system, then our tolerance for error is a bit lower.

    Thus a little overcompression is acutally good for generalizing rather than parroting.
    A lot of overcompression leads to bad predictions.

    --
    Some drink at the fountain of knowledge. Others just gargle.