98
votes
Crack CAPTCHA using deep learning
Here is one example using a convolutional neural network (CNN) to crack the CAPTCHA. We will use a CAPTCHA library to generate sample CAPTCHA images and then train a neural network to decode these ...
60
votes
What are the Wolfram Language's relative strengths for machine learning?
I have worked in pattern classification and machine learning for decades, taught the subject in a number of elite academic departments, am writing the third edition of Pattern classification by Duda, ...
59
votes
Object detection and localization using neural network
Introduction
An object detection problem can be approached as either a classification problem or a regression problem. As a classification problem, the image is divided into small patches, each of ...
48
votes
What are the Wolfram Language's relative strengths for machine learning?
Mathematica doesn't have the depth of algorithm support that is present in R or Python. Julia has much more limited algorithm support but does exhibit a good turn of speed.
The few algorithms that ...
38
votes
Accepted
Mathematica command that allows it to read my intentions
Indeed, this functionality still exists, but it has been moved into its own package.
Load the package:
Needs["aBetterProgrammer`"]
You will have access to such ...
Community wiki
37
votes
Q&A Mathematica v.11 Neural Networks: A comprehensive look at Layers, Net Functions, and pioneering into this [[experimental]] code
Thank you for your summary. I would like to clarify and correct a few of your points.
however, Mathematica - being proprietary - does not make it clear as to which algorithms they choose to use to ...
37
votes
Accepted
RNN in Mathematica?
This is actually a useful question, because it gives an opportunity for us to communicate with the community about what is coming, so we can get feedback. So here is some preliminary information about ...
33
votes
Accepted
How can I detect if an image is of poor quality?
As was correctly noted in comments, out-of-focus images cannot been correctly detected by a simple gradient filter since out-of-focus images can have sharp edges. I propose another simple idea to ...
29
votes
Accepted
How to perform document classification (i.e. extracting topics from text)?
What you're describing is Topic modeling. Your link describes Latent Dirichlet Allocation (LDA), which is a popular model. You mention that you would like to use an expectation-maximization algorithm ...
29
votes
Accepted
Generative Adversarial Network
I wrestled with this for a while and got some kind of results, but nowhere near the great performance for which GANs are famous. Ultimately, they're absurdly sensitive to hyperparameters and ...
27
votes
How to export an MXNet?
It seems the model file in MXNet (checkpoint) is defined by two files: a ".json" file and a ".params" file. The json file contains the definition of the network, and the params file contains the ...
26
votes
Accepted
Biased results when using Method -> "RandomForest" in Predict
Can anyone explain the source of this bias and how I might go about fixing it?
The source of the bias is the low number of features used to grow the trees (mtry in ...
26
votes
Accepted
Generalized Backpropagation for Neural Networks (e.g. DeepDream)
Sebastian mentioned in his answer that deepdream can be possible using NetDerivative. Here are my attempts following his outlines.
Instead of using the inception ...
25
votes
How can I export my learned ClassiferFunction[] and PredictorFunction[]s?
It's on our list of things to do, but there are many other areas we want to cover, such as custom feature functions, customizable feature selection, boosting, NLP, deep learning of neural networks, ...
24
votes
Accepted
How to know the internal algorithms of functions like Predict or Classify?
If you want to have a description of the method used by a given ClassifierFunction you can do:
...
22
votes
Mathematica command that allows it to read my intentions
Since version 11 most commands finally support the Interpretation option: Interpretation -> "Literal" being the classical (...
Community wiki
22
votes
Mathematica command that allows it to read my intentions
I tend to use a pattern matching approach:
myCode/.{x_?BugQ:>BugStrip[x],x_?TypoQ:>Detypo[x],x_?WrongSignQ:>-x,x_?OffBy2PiQ:>x*2\[Pi]}
With the usual ...
Community wiki
21
votes
Accepted
Machine learning. SVM algorithm
As of Version 10 , Mathematica has a built in function Classify, which implements support vector machines and some other common machine learning algorithms.
...
21
votes
Accepted
How to monitor the process of Neural Network Learning
You can pass the undocumented option "ShowTrainingProgress" -> False to turn off the training progress blob thing.
As for monitoring the progress yourself, ...
21
votes
Generalized Backpropagation for Neural Networks (e.g. DeepDream)
If you have an inception model, its mostly possible using hidden functionality (but without GPU training). The steps would look like this:
Cut the inception model at some level using ...
20
votes
Accepted
Trainable WEKA segmentation of images
Edit
The use of two median filters is the bottleneck of my method, and you indicated in a comment on nikie's answer that speed might be of importance to you.
You can replace ...
20
votes
Accepted
How to detect loops in a vector field?
Maybe you can transform this into an easier problem: If you were instead looking for lines that are at any point perpendicular to your vector field:
(that's easy, it's just a coordinate ...
20
votes
How can I determine the importance of variables from Classify?
General remarks
I am not aware of built-in functions for retrieval of the variable importance from/with Classify and related functions.
I implemented (and ...
19
votes
Accepted
What is behind experimental function: FindFormula?
The Experimental function FindFormula[] at the moment is using a combination of different methods: it combines non linear regression with Markov chain Monte Carlo ...
19
votes
Accepted
Using a Convolutional Neural Network for time series classification
Here's the code. What I mentioned in the Q&A session is using ReshapeLayer to turn the input vector into a 1-channel, flat tensor that ConvolutionLayer can operate on, not to actually use images, ...
19
votes
Q&A Mathematica v.11 Neural Networks: A comprehensive look at Layers, Net Functions, and pioneering into this [[experimental]] code
Layers
BatchNormalizationLayer
There are several layers introduced in v.11 that can not be used uninitialized, this is one of them. Input must be either a rank 1 or rank 3 tensor. To be honest, I do ...
19
votes
Mathematica command that allows it to read my intentions
This function was deprecated in V4.2, being succeeded by CellularAutomaton.
Since your answer is hidden somewhere in rules like 110, why reinvent the wheel with <...
Community wiki
18
votes
Accepted
Rapid density estimation and rendering of decision regions
The biggest issue you are running in to is that you have to recompute the density estimates each time you sample a new point. You need the estimators to be pre-evaluated.
...
18
votes
Accepted
Importing a grid of numbers from an image (sudoku like)
1 - Summary of a simple solution
In this particular DIGIT case there is a very simple solution based on neural nets (NNs)trained on MNIST Data. It is just a few lines of code:
...
17
votes
What are the Wolfram Language's relative strengths for machine learning?
From my perspective, (I was the original developer for Evolved Analytics' DataModeler Mathematica add-on package, www.evolved-analytics.com), what Mathematica brings to the table is the semi-seamless ...
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