All Questions
3,715
questions with no upvoted or accepted answers
14
votes
1
answer
244
views
Will parameter sweeping on one split of data followed by cross validation discover the right hyperparameters?
Let's call our dataset splits train/test/evaluate. We're in a situation where we require months of data. So we prefer to use the evaluation dataset as infrequently as possible to avoid polluting our ...
13
votes
3
answers
494
views
Can some one help me understand this paragraph from Nvidia's progressive GAN paper?
Furthermore, we observe that mode collapses traditionally
plaguing GANs tend to happen very quickly, over the course of a dozen mini-batches. Commonly
they start when the discriminator overshoots, ...
12
votes
0
answers
260
views
What is the number of neurons required to approximate a polynomial of degree n?
I learned about the universal approximation theorem from this guide. It states that a network even with a single hidden layer can approximate any function within some bound, given a sufficient number ...
10
votes
0
answers
276
views
Extending FaceNet’s triplet loss to object recognition
FaceNet uses a novel loss metric (triplet loss) to train a model to output embeddings (128-D from the paper), such that any two faces of the same identity will have a small Euclidean distance, and ...
9
votes
0
answers
149
views
Why is my GAN more unstable with bigger networks?
I am working with generative adversarial networks (GANs) and one of my aims at the moment is to reproduce samples in two dimensions that are distributed according to a circle (see animation). When ...
9
votes
2
answers
366
views
Back-of-the-envelope machine learning (specifically neural networks) calculations
There is a popular story regarding the back-of-the-envelope calculation performed by a British physicist named G. I. Taylor. He used dimensional analysis to estimate the power released by the ...
9
votes
0
answers
764
views
Are Cellular Neural Networks one type of Neural Networks?
I am researching Cellular Neural Networks and have already read Chua's two articles (1988). In cellular neural networks, a cell is only in relation with its neighbors. So it is easy to use them for ...
8
votes
1
answer
196
views
How to deal with a small amount of labeled samples?
I'm trying to develop skills to deal with very small amounts of labeled samples (250 labeled/20000 total, 200 features) by practicing on Kaggle "Don't Overfit" dataset (Traget_Practice have ...
8
votes
1
answer
179
views
Why are documents kept separated when training a text classifier?
Most of the literature considers text classification as the classification of documents. When using the bag-of-words and Bayesian classification, they usually use the statistic TF-IDF, where TF ...
7
votes
1
answer
111
views
Validation accuracy higher than training accurarcy
I implemented the unet in TensorFlow for the segmentation of MRI images of the thigh. I noticed I always get a higher validation accuracy by a small gap, independently of the initial split. One ...
7
votes
0
answers
200
views
Is the Bellman equation that uses sampling weighted by the Q values (instead of max) a contraction?
It is proved that the Bellman update is a contraction (1).
Here is the Bellman update that is used for Q-Learning:
$$Q_{t+1}(s, a) = Q_{t}(s, a) + \alpha*(r(s, a, s') + \gamma \max_{a^*} (Q_{t}(s',
...
7
votes
2
answers
256
views
How can I solve the zero subset sum problem with hill climbing?
I want to solve the zero subset sum problem with the hill-climbing algorithm, but I am not sure I found a good state space for this.
Here is the problem: consider we have a set of numbers and we want ...
7
votes
0
answers
76
views
Normalizing Normal Distributions in Thompson Sampling for online Reinforcement Learning
In my implementation of Thompson Sampling (TS) for online Reinforcement Learning, my distribution for selecting $a$ is $\mathcal{N}(Q(s, a), \frac{1}{C(s,a)+1})$, where $C(s,a)$ is the number of times ...
7
votes
1
answer
79
views
What is the impact of using multiple BMUs for self-organizing maps?
Here's a sort of a conceptual question. I was implementing a SOM algorithm to better understand its variations and parameters. I got curious about one bit: the BMU (best matching unit == the neuron ...
7
votes
1
answer
104
views
How does the network know which objects to track in the paper "Label-Free Supervision of Neural Networks with Physics and Domain Knowledge"?
I was reading the paper Label-Free Supervision of Neural Networks with Physics and Domain Knowledge, published at AAAI 2017, which won the best paper award.
I understand the math and it makes sense. ...
7
votes
1
answer
222
views
Why do layered neural nets struggle with continous data?
In this article here, the writer claims that a new type of neural net is required to deal with data that is both continuous, and also sparsely sampled.
It was my understanding that this was the ...
7
votes
0
answers
1k
views
Is there a difference in the architecture of deep reinforcement learning when multiple actions are performed instead of a single action?
I've built a deep deterministic policy gradient reinforcement learning agent to be able to handle any games/tasks that have only one action. However, the agent seems to fail horribly when there are ...
6
votes
0
answers
81
views
How can a neural network distinguish a rotated 6 and 9 digits?
Rotated MNIST is a popular dataset for benchmarking models equivariant to rotations on $\mathbb{R}^2$, described by $SO(2)$ group or its discrete subgroups like $\mathbb{Z}^{n}$:
Group equivariant ...
6
votes
1
answer
263
views
What are the state-of-the-art results in OpenAI's gym environments?
What are the state-of-the-art results in OpenAI's gym environments? Is there a link to a paper/article that describes them and how these SOTA results were calculated?
6
votes
1
answer
112
views
Are there transformer-based architectures that can produce fixed-length vector encodings given arbitrary-length text documents?
BERT encodes a piece of text such that each token (usually words) in the input text map to a vector in the encoding of the text. However, this makes the length of the encoding vary as a function of ...
6
votes
2
answers
80
views
Can training a model on a dataset composed by real images and drawings hurt the training process of a real-world application model?
I'm training a multi-label classifier that's supposed to be tested on underwater images. I'm wondering if feeding the model drawings of a certain class plus real images can affect the results badly. ...
6
votes
1
answer
157
views
How could an AI detect whether an enemy in a game can be blocked off/trapped?
Imagine a game played on a 10x10 grid system where a player can move up down left or right and imagine there are two players on this grid: An enemy and you. In this game, there are walls on the grid ...
6
votes
0
answers
100
views
How do neural network topologies affect GPU/TPU acceleration?
I was thinking about different neural network topologies for some applications. However, I am not sure how this would affect the efficiency of hardware acceleration using GPU/TPU/some other chip.
If, ...
6
votes
1
answer
315
views
An intuitive explanation of Adagrad, its purpose and its formula
It (Adagrad) adapts the learning rate to the parameters, performing smaller updates
(i.e. low learning rates) for parameters associated with frequently occurring features, and larger updates (i.e. ...
6
votes
0
answers
289
views
Why don't people use nonlinear activation functions after projecting the query key value in attention?
Why don't people use nonlinear activation functions after projecting the query key value in attention?
It seems like doing this would lead to much-needed nonlinearity, otherwise, we're just doing ...
6
votes
0
answers
196
views
What are the main benefits of using Bayesian networks?
I have some trouble understanding the benefits of Bayesian networks.
Am I correct that the key benefit of the network is that one does not need to use the chain rule of probability in order to ...
6
votes
0
answers
94
views
What are the current trends/open questions in logics for knowledge representation?
What are the future prospects in near future from a theoretical investigation of description logics, and modal logics in the context of artificial intelligence research?
6
votes
0
answers
4k
views
Does it make sense to use batch normalization in deep (stacked) or sparse auto-encoders?
Does it make sense to use batch normalization in deep (stacked) or sparse auto-encoders?
I cannot find any resources for that. Is it safe to assume that, since it works for other DNNs, it will also ...
6
votes
1
answer
300
views
Which neural networks are suitable for visual place recognition?
I am doing a project on visual place recognition in changing environments. The CNN used here is mostly AlexNet, and a feature vector is constructed from layer 3.
Does anyone know of similar work ...
5
votes
0
answers
58
views
Is there a venue to publish negative results in AI/ML domain?
Negative results occur frequently in AI/ML research (and perhaps in other domains too). Most of the time, these results are not published. This is mostly because your typical AI/ML conference doesn't ...
5
votes
0
answers
67
views
Proof that there always exists a dominating policy in an MDP
I think that it is common knowledge that for any infinite horizon discounted MDP $(S, A, P, r, \gamma)$, there always exists a dominating policy $\pi$, i.e. a policy $\pi$ such that for all policies $\...
5
votes
0
answers
103
views
Why can't cognitive architectures achieve general intelligence?
Newbie here.
I recently read about cognitive architectures (see: https://en.wikipedia.org/wiki/Cognitive_architecture). They are supposed to be modeled after the human mind and represent a promising ...
5
votes
0
answers
45
views
Are generative models actually used in practice for industrial drug design?
I just finished reading this paper MoFlow: An Invertible Flow Model for Generating Molecular Graphs.
The paper, which is about generating molecular graphs with certain chemical properties improved the ...
5
votes
0
answers
52
views
Origins of the name of convolutional neural networks
Convolutional neural networks (CNNs) contain convolutional layers. In modern deep learning libraries such as Tensorflow and PyTorch among others, convolutional layers are implemented by using the ...
5
votes
0
answers
54
views
It is possible to use deep learning to give approximate solutions to NP-hard graph theory problems?
It is possible to use deep learning to give approximate solutions to NP-hard graph theory problems?
If we take, for example, the travelling salesman problem (or the dominating set problem). Let's say ...
5
votes
0
answers
445
views
Wasserstein GAN: Implemention of Critic Loss Correct?
The WGAN paper concretely proposes Algorithm 1 (cf. page 8). Now, they also state what their loss for the critic and the generator is.
When implementing the critic loss (so lines 5 and 6 of Algorithm ...
5
votes
0
answers
81
views
Why is there a Uniform and Normal version of He / Xavier initialization in DL libraries?
Two of the most popular initialization schemes for neural network weights today are Xavier and He. Both methods propose random weight initialization with a variance dependent on the number of input ...
5
votes
0
answers
105
views
$\frac{P(x_1 \mid y, s = 1) \dots P(x_n \mid y, s = 1) P(y \mid s = 1)}{P(x \mid s = 1)}$ indicates that naive Bayes learners are global learners?
I am currently studying the paper Learning and Evaluating Classifiers under Sample Selection Bias by Bianca Zadrozny. In section 3. Learning under sample selection bias, the author says the following:
...
5
votes
0
answers
105
views
Why Pixel RNN (Row LSTM) can capture triangular contexts?
I'm reading the paper Pixel Recurrent Neural Network. I have a question about Row LSTM. Why Row LSTM can capture triangular contexts?
In this paper,
the kernel of the one-dimensional convolution ...
5
votes
1
answer
115
views
How to classify human actions?
I'm quite new to machine learning (I followed the Coursera course of Andrew Ng and now starting deeplearning.ai courses).
I want to classify human actions real-time like:
Left-arm bended
Arm above ...
5
votes
0
answers
2k
views
How many training data is required for GAN?
I'm beginning to study and implement GAN to generate more datasets. I'll just try to experiment with state-of-the-art GAN models as described here https://paperswithcode.com/sota/image-generation-on-...
5
votes
0
answers
117
views
Are there any easy ways to create annotated training images for object detection?
For the purposes of object detection, are there any easy ways to create annotated training images? For example, if we have $10,000$ images and want to draw bounding boxes on 2 objects for each image, ...
5
votes
2
answers
1k
views
What evaluation metric are used for sequence-to-sequence prediction problems?
I am solving many sequence-to-sequence prediction problems using RNN/LSTM.
What type of evaluation metrics can be used for sequence prediction problems?
One metric is the mean squared error (MSE) ...
5
votes
0
answers
431
views
How is the rollout from the MCTS implemented in both of the AlphaGo Zero and the AlphaZero algorithms?
In the vanilla Monte Carlo tree search (MCTS) implementation, the rollout is usually implemented following a uniform random policy, that is, it takes random actions until the game is finished and only ...
5
votes
1
answer
168
views
How do big companies, like Facebook, model individuals and their interaction?
As a layman in AI, I want to get an idea of how big data players, like Facebook, model individuals (of which they have so many data).
There are two scenarios I can imagine:
Neural networks build ...
5
votes
0
answers
63
views
What is meant by "model discriminability for local patches within the receptive field"?
In the abstract of the paper Network In Network, the authors write
We propose a novel deep network structure called "Network In Network"(NIN) to enhance model discriminability for local ...
5
votes
0
answers
309
views
What are the ways to calculate the error rate of a deep Convolutional Neural Network, when the network produces different results using the same data?
I am new to the object recognition community. Here I am asking about the broadly accepted ways to calculate the error rate of a deep CNN when the network produces different results using the same data....
5
votes
0
answers
114
views
Speciation in NEAT - Advantages of keeping stable number of species
I found several methods for setting the compatibility distance in NEAT: some normalize it, some don't, some automatically adjust it.
In a few tests I am running, using normalized static compatibility ...
5
votes
0
answers
210
views
Is a mathematical formula a form of intelligence?
Warning: This question takes us into VALIS territory, but I wouldn't underestimate the profundity of that particular philosopher.
There is a non-AI definition of intelligence which is simply "...
5
votes
1
answer
94
views
Correcting 'bad' translations in a sequence-to-sequence neural machine translation model
In working with basic sequence-to-sequence models for machine translation I have been able to achieve decent results. But inevitably some translations are not optimal or just flat-out incorrect. I am ...