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1. Most neural networks are essentially very large correlation engines that will hone in on any statis-
tical, potentially spurious pattern that allows them to model the observed data more accurately.
2. Generative adversarial networks (GANs) have been extremely effective in approximating complex distributions
of high-dimensional, input data samples.
3. The learning objective is to learn the best parameterization of those embeddings such that the correct answer
has higher likelihood among all possible answers.
4. In contrast with past approaches in AI, modern deep learning methods (LeCun et al., 2015; Schmidhuber, 2015; Goodfellow et al.,
2016) often follow an “end-to-end” design philosophy which emphasizes minimal a priori representational and computational
assumptions, and seeks to avoid explicit structure and “hand-engineering”. This emphasis has fit well with—and has perhaps been
affirmed by—the current abundance of cheap data and cheap computing resources, which make trading off sample efficiency for more
flexible learning a rational choice. The remarkable and rapid advances across many challenging domains, from image
classification (Krizhevsky et al., 2012;Szegedy et al., 2017), to natural language processing (Sutskever et al., 2014;
Bahdanau et al., 2015), to game play (Mnih et al., 2015; Silver et al., 2016; Moravˇc ́ık et al., 2017), are a testament to this
minimalist principle. A prominent example is from language translation, where sequence-to-sequence approaches (Sutskever et al.,
2014; Bahdanau et al., 2015) have proven very effective without using explicit parse trees or complex relationships between
linguistic entities.
5. Bengio:没法立刻判断,都是几年后才能意识到。通常情况是双方的期望之间存在不匹配,与企业界的合作必须小心这一点,你需要明确告诉对方,学术界的人可以
为他们做什么而不能做什么。重要的是让他们明白学术不是廉价劳动力,也不会产出产品,而是可以创造一些能改变商业模式的想法。企业需要明白,这只是投资的一部
分。他们还需要让内部人员将算法和原型转变为产品,否则合作注定要失败。说实话很多人不愿意听到这些,因为这意味着企业要花更多的钱。但是这些话不得不说。
Bengio:倾听你的直觉。许多人缺乏自信,因此他们错过了机会。作为研究人员,我们的主要工作是提供有意义的想法来推动知识进步。这些想法隐藏在我们大脑某个
地方,我们需要培养一种能力,让这些想法能够发展成熟并发布出来,因此你需要有足够的时间来思考,而不是一直编程,写作甚至阅读。多考虑一下那些让你烦恼的大
问题。
6. https://www.zhihu.com/question/21342077
Elon Musk: Well, I do think there’s a good framework for thinking. It is physics. You know, the sort of first principles reasoning.
Generally I think there are — what I mean by that is, boil things down to their fundamental truths and reason up from there,
as opposed to reasoning by analogy. Through most of our life, we get through life by reasoning by analogy, which essentially
means copying what other people do with slight variations. And you have to do that. Otherwise, mentally, you wouldn’t be able
to get through the day. But when you want to do something new, you have to apply the physics approach. Physics is really
figuring out how to discover new things that are counterintuitive, like quantum mechanics. It’s really counterintuitive. So I
think that’s an important thing to do, and then also to really pay attention to negative feedback, and solicit it, particularly
from friends. This may sound like simple advice, but hardly anyone does that, and it’s incredibly helpful.
7. Goodfellow's twitter on opinion on deep learning and convex cost constraint, also another guy's rebuttal
https://twitter.com/goodfellow_ian/status/964168396072828928
8. Michael I. Jordan:
The developments which are now being called “AI” arose mostly in the engineering fields associated with low-level pattern recognition
and movement control, and in the field of statistics — the discipline focused on finding patterns in data and on making well-founded
predictions, tests of hypotheses and decisions.
...
One could simply agree to refer to all of this as “AI,” and indeed that is what appears to have happened. Such labeling may come as a
surprise to optimization or statistics researchers, who wake up to find themselves suddenly referred to as “AI researchers.”
...
Of course, classical human-imitative AI problems remain of great interest as well. However, the current focus on doing AI research via
the gathering of data, the deployment of “deep learning” infrastructure, and the demonstration of systems that mimic certain
narrowly-defined human skills — with little in the way of emerging explanatory principles — tends to deflect attention from major open
problems in classical AI.
...
We need to realize that the current public dialog on AI — which focuses on a narrow subset of industry and a narrow subset of
academia — risks blinding us to the challenges and opportunities that are presented by the full scope of AI, IA and II.
...
In the current era, we have a real opportunity to conceive of something historically new — a human-centric engineering discipline.
9. For thirty years, the state-of-the-art in speech recognition used hidden Markov models with Gaussian mixtures as output
distributions. These models were easy to learn on small computers, but they had a representational limitation that was
ultimately fatal: The one-of-n representations they use are exponentially inefficient compared with, say, a recurrent neural
network that uses distributed representations. To double the amount of information that an HMM can remember about the string it
has generated so far, we need to square the number of hidden nodes. For a recurrent net we only need to double the number of
hidden neurons.
Now that convolutional neural networks have become the dominant approach to object recognition, it makes sense to ask whether
there are any exponential inefficiencies that may lead to their demise.
10. The theory of reinforcement learning provides a normative account, deeply rooted in psychological and neuroscientific
perspectives on animal behaviour, of how agents may optimize their control of an environment. To use reinforcement learning
successfully in situations approaching real-world complexity, however, agents are confronted with a difficult task: they must
derive efficient representations of the environment from high-dimensional sensory inputs, and use these to generalize past
experience to new situations. Remarkably, humans and other animals seem to solve this problem through a harmonious combination
of reinforcement learning and hierarchical sensory processing systems, the former evidenced by a wealth of neural data revealin
g notable parallels between the phasic signals emitted by dopaminergic neurons and temporal difference reinforcement learning
algorithms.
11. Deep learning, Yann LeCun, Yoshua Bengio & Geoffrey Hinton
The key aspect of deep learning is that these layers of features are not designed by human engineers: they are learned from
data using a general-purpose learning procedure.
...
For classification tasks, higher layers of representation amplify aspects of the input that are important for discrimination
and suppress irrelevant variations.
...
The issue of representation lies at the heart of the debate between the logic-inspired and the neural-network-inspired
paradigms for cognition. In the logic-inspired paradigm, an instance of a symbol is something for which the only property
is that it is either identical or non-identical to other symbol instances. It has no internal structure that is relevant to
its use; and to reason with symbols, they must be bound to the variables in judiciously chosen rules of inference. By contrast,
neural networks just use big activity vectors, big weight matrices and scalar non-linearities to perform the type of fast
'intuitive' inference that underpins effortless commonsense reasoning.
...
Ultimately, major progress in artificial intelligence will come about through systems that combine representation learning
with complex reasoning. Although deep learning and simple reasoning have been used for speech and handwriting recognition
for a long time, new paradigms are needed to replace rule-based manipulation of symbolic expressions by operations on large
vectors.
12. About CapsuleNet
Equivariance and invariance are also useful properties when aiming to produce data representations that disentangle factors of
variation, which is one goal of capsule networks.
...
They aim to hard-wire the ability to disentangle the pose of an object from the evidence of its existence. This is done by
encoding the output of one layer as a tuple of a pose vector and an activation, leading to a clearer geometric interpretation
of learned representations. They are inspired by the human vision and detect linear, hierarchical relationships occurring in
the data.
...
The votes are used to compute a proposal for an output pose by a variant of weighted averaging. The weights are then
iteratively refined using distances between votes and the proposal. Last, an agreement value is computed as output
activation, which encodes how strong the transformed input poses agree on the output pose. The capsule layer outputs a set
of tuples (M, a), each containing pose matrix and agreement (as activation) for one output capsule.
...
During inference propagation, the principle of coincidence filtering is employed to activate higher-level capsules and set
up part-whole relationships among capsule entities. Such part-whole hierarchy lays a solid foundation for viewpoint-invariant
recognition, which can be implemented through dynamic routing or EM routing.
...
The success of capsule networks lies in their ability to preserve more information about the input by replacing max-pooling layers
with convolutional strides and dynamic routing, allowing for preservation of part-whole relationships in the data. This preservation
of the input is demonstrated by reconstructing the input from the output capsule vectors.
...
Viewpoint changes in capsule network are linear effects on the pose matrices of the parts and the whole between different
capsules layers.
...
Hinton wants to revamp the approach to AI because there is little evidence inside the natural sciences that "backprop" and
large "training data" are used during human learning. Unsupervised and reinforcement approaches share much more in common
with what we know about the human brain and its capacity to adapt to its environment. But the current approach to
unsupervised learning (for deep learning approaches) is really just converting an unsupervised problem into a supervised
one so that we can apply backdrop (e.g. GANs, autoencoders, etc.). So in some sense the progress to move towards human
learning is much slower than promoted. The issues become even more challenging when we realize the use of EM in generative
models usually degrades into an optimization problem that is best solved using backprop anyway. So Hinton's frustration
with the current approach is likely shared by others. The take home message is that the SOTA is not moving away from large
training sets, and is not moving towards how people learn.
...
Blending more traditional ML approaches with deep learning may in fact bring us closer to human intelligence (e.g. using
kNNs to implement the availability and anchoring heuristics, or perhaps even analogy). Real neurons are vastly more complex
than the dumb ANNs we construct with our models, and backprop is much too wasteful of training data to be the way forward.
Backprop is likely a placeholder until we find ways to realistically move towards unsupervised, reinforcement, and
human-heuristic approaches to learning.
13. Operator notation provides a higher level of mathematical abstraction, allowing the theorems derived below to express
the relationship between transformations that we are interested in (e.g. image formation) rather than being tied up in the
underlying functions being acted upon (e.g. light fields and photographs).
14. (optical flow) Small motion minimizes the correspondence problem between successive images, but sacrifices depth resolution
because of the small baseline between consecutive image pairs.
Life:
cross my/your heart and hope to die
A sexy voice is a sexy voice regardless of dailect
It's hopeless He lets me run away
dry humor
You keep telling yourself what you know, but what do you believe what do you feel
Deep down, I'm really superficial.
You want too much
Mirror mirror on the wall, who's the fairest of them all
side character
他死的很糟糕是因为过去活的很糟糕
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