I'm kinda new to Neural Networks and just started to learn coding them by trying some examples.
Two weeks ago I was searching for an interesting challenge and I found one. But I'm about to give up because it seems to be too hard for me... But I was curious to know if anyone of you is able to solve this?
The Problem: Assume there are ".htm"-files that contain tables about the same topic. But the table structure isn't the same for every file. For example: We have a lot ".htm"-files containing information about teachers substitutions per day per school. Because the structure of those ".htm"-files isn't the same for every file it would be hard to program a parser that could extract the data from those tables. So my thought was that this is a task for a Neural Network.
First Question: Is it a task a Neural Network can/should handle or am I mistaken by that?
Because for me a Neural Network seemed to fit for this kind of a challenge I tried to thing of an Input. I came up with two options:
First Input Option: Take the HTML Code (only from the body-tag) as string and convert it as Tensor
Second Input Option: Convert the HTML Tables into Images (via Canvas maybe) and feed this input to the DNN through Conv2D-Layers.
Second Question: Are those Options any good? Do you have any better solution to this?
After that I wanted to figure out how I would make a DNN output this heavily dynamic data for me? My thought was to convert my desired JSON-Output into Tensors and feed them to the DNN while training and for every prediction i would expect the DNN to return a Tensor that is convertible into a JSON-Output...
Third Question: Is it even possible to get such a detailed Output from a DNN? And if Yes: Do you think the Output would be suitable for this task?
Last Question: Assuming all my assumptions are correct - Wouldn't training this DNN take for ever? Let's say you have a RTX 2080 ti for it. What would you guess?
I guess that's it. I hope i can learn a lot from you guys!
(I'm sorry about my bad English - it's not my native language)
Addition:
Here is a more in-depth Example. Lets say we have a ".htm"-file that looks like this:
The task would be to get all the relevant informations from this table. For example:
All Students from Class "9c" don't have lessons in their 6th hour due to cancellation.
1) This is not particularly suitable problem for a Neural Network, as you domain is a structured data with clear dependcies inside. Tree based ML algorithms tend to show much better results on such problems.
2) Both you choices of input are very unstructured. To learn from such data would be nearly impossible. The are clear ways to give more knowledge to the model. For example, you have the same data in different format, the difference is only the structure. It means that a model needs to learn a mapping from one structure to another, it doesn't need to know any data. Hence, words can be Tokenized with unique identifiers to remove unnecessary information. Htm data can be parsed to a tree, as well as json. Then, there are different ways to represent graph structures, which can be used in a ML model.
3) It seems that the only adequate option for output is a sequence of identifiers pointing to unique entities from text. The whole problem then is similar to Seq2Seq best solved by RNNs with an decoder-encoder architecture.
I believe that, if there is enough data and htm files don't have huge amount of noise, the task can be completed. Training time hugely depends on selected model and its complexity, as well as diversity of initial data.
Related
I'm relatively new and am still learning the basics. I've used NVIDIA DIGITS in the past, and am now looking at Tensorflow. While I've been able to fumble my way around creating some models for a few projects I'm working on, I really want to start diving deeper into what I'm doing, how I'm doing it, and ultimately a better understanding of why.
One area that I would like to start with is the Images that I'm using for training and testing. Can anyone point me to a blog, an article, a paper, or give me some insight in what I need to consider when selecting images to train a new model on. Up until recently, I've been using datasets that have already been selected and that are available for download. Lets say I'm going to start working on a project that involves object detection of ships from a variety of distances and angles.
So my thoughts would be
1) I need a large quantity of images.
2) The images need to contain ships of the different types I would like to detect. (lets just say one class, ships, don't care what type of ships)
3) I also need to have images that have a great variety of distance perspective for the different types of ships.
Ultimately, my thoughts are that the images need to reflect the distance, perspective, and types of ships I would ideally want to identify from the video. Seems simple enough.
However, there are a number of questions
Does the images need to be the same/similar resolution as the camera I'll be using, for best results?
Does the images all need to be the same resolution?
Can I use a single image and just digitally zoom out on the image to give the illusion of different distances?
I'm sure there are a number of other questions that I'm not asking, or should be asking. Are there any guide lines available for creating a solid collection of images to use when creating the collection of images for training and validation?
I recommend thinking through end to end, like would you need to classify ship models as a next step? I recommend going through well known public datasets and actually work with the structure, how to store data, labels, how to handle preprocessing etc.
More importantly, what are you trying to achieve? Talking to experts in the topic does help greatly while preparing your own dataset.
Use open source images if you can, e.g. flickr, google, imagenet.
No, you don't need them to be the same resolution.
It is not ideal to zoom in/out images to use in different categories. Preprocessing images and data augmentation already does this to create more distant representations of the same class. This is why I would recommend hands on approach with an existing dataset first.
Yes, what you need is many, different representations of classes, and a roughly balanced dataset of classes. If you define your data structure well in the beginning, it will save you a ton of time as you won't have to make changes often.
Recently I stared toying with tensor flow, dnns etc. now I'm trying to implement something more serious, information retrieval from short sentences (doctor instructions).
Unfortunately the dataset I have is, as always, quite "dirty". As I'm trying to use word embeddings, I actually need "clean" data. Take one example:
"Take two pilleach day". There is a missing white space between pill and each. I am implementing "tokenizer improver" to look at each sentence and propose new tokenization based on joint probability of each word in sentence given the frequency of terms in whole document (tf) . As I was doing it today, a thought came to my mind: why bother writing suboptimal solution for this problem when I can employ powerful learning algorithms such as Lstm networks to do that for me. However, as of today, I have only a feeling that it's actually possible to do that. As we know, feelings are not best when it comes to architecting such complex problems. I don't know where to begin: what should be my training set and learning goal.
I know this is a broad question, but I know there are many brilliant people with more knowledge about tensorflow and neural nets, so I'm sure that somebody has either already solved similar problem or just knows how to approach this problem.
Any guidance is welcome, I do not except you to solve this for me of course:)
Besos and all the best to all the tensorflow community:)
Having the same issue. I solved it by using a character level net. Basically I rewrote Character-Aware Neural Language Models, kicked out the whole "words"-elements and just stayed with the caracter level.
Training Data: I took the data I had, as dirty as it was, used the dirty data as targets and made it even more dirty to create inputs.
So your "Take two pilleach day" will be learned as in many cases you do have a clean and similar phrase, e.g. "Take one pill each morning" that with the regime mentioned will serve as target and you train the net on destroyed inputs like "Take oe pileach mornin"
having read this article about a guy who uses tensorflow to sort cucumber into nine different classes I was wondering if this type of process could be applied to a large number of classes. My idea would be to use it to identify Lego parts.
At the moment, a site like Bricklink describes more than 40,000 different parts so it would be a bit different than the cucumber example but I am wondering if it sounds suitable. There is no easy way to get hundreds of pictures for each part but does the following process sound feasible :
take pictures of a part ;
try to identify the part using tensorflow ;
if it does not identify the correct part, take more pictures and feed the neural network with them ;
go on with the next part.
That way, each time we encounter a new piece we "teach" the network its reference so that it can better be recognized the next time. Like that and after hundreds of iterations monitored by a human, could we imagine tensorflow to be able to recognize the parts? At least the most common ones?
My question might sound stupid but I am not into neural networks so any advice is welcome. At the moment I have not found any way to identify a lego part based on pictures and this "cucumber example" sounds promising so I am looking for some feedback.
Thanks.
You can read about the work of Jacques Mattheij, he actually uses a customized version of Xception1 running on https://keras.io/.
The introduction is Sorting 2 Metric Tons of Lego.
In Sorting 2 Tons of Lego, The software Side you can read:
The hard challenge to deal with next was to get a training set large
enough to make working with 1000+ classes possible. At first this
seemed like an insurmountable problem. I could not figure out how to
make enough images and to label them by hand in acceptable time, even
the most optimistic calculations had me working for 6 months or longer
full-time in order to make a data set that would allow the machine to
work with many classes of parts rather than just a couple.
In the end the solution was staring me in the face for at least a week
before I finally clued in: it doesn’t matter. All that matters is that
the machine labels its own images most of the time and then all I need
to do is correct its mistakes. As it gets better there will be fewer
mistakes. This very rapidly expanded the number of training images.
The first day I managed to hand-label about 500 parts. The next day
the machine added 2000 more, with about half of those labeled wrong.
The resulting 2500 parts where the basis for the next round of
training 3 days later, which resulted in 4000 more parts, 90% of which
were labeled right! So I only had to correct some 400 parts, rinse,
repeat… So, by the end of two weeks there was a dataset of 20K images,
all labeled correctly.
This is far from enough, some classes are severely under-represented
so I need to increase the number of images for those, perhaps I’ll
just run a single batch consisting of nothing but those parts through
the machine. No need for corrections, they’ll all be labeled
identically.
A recent update is Sorting 2 Tons of Lego, Many Questions, Results.
1CHOLLET, François. Xception: Deep Learning with Depthwise Separable Convolutions. arXiv preprint arXiv:1610.02357, 2016.
I have started this using IBM Watson's Visual Recognition.
I had six different bricks to be recognized on the transport belt background.
I am actually thinking about tensorflow, since I can have it running locally.
The codelab : TensorFlow for Poets, describes almost exactly what you want to achieve,
For a demo of the Watson version:
https://www.ibm.com/developerworks/community/blogs/ibmandgoogle/entry/Lego_bricks_recognition_with_Watosn_lego_and_raspberry_pi?lang=en
I'm doing a research on the author name disambiguation problem. I want to make some experiments. I want to perform clustering on citation records. My dataset consist of 2000 xml records. I need testing data. The dataset that I'm using is not popular and I need to make testing data manually. I don't know how to do so. I need instruction of how to make testing data manually. Note: I want to compare the performance of a set of techniques in solving the author name disambiguation problem, So I must perform testing.
Even though it is not really clear what kind of testing you want to perform, but general answer to the issue at hand - trying to artificially create more data from the data you have at hand - is a bootstrap. In general it is technique when you perform sampling with replacement from your dataset as many times as you want. It randomly picks up some element from your data repetitively untill you get a sample of the size you want. The sample you get could be larger than your original dataset but should have similar (from statistical point of view) as your original dataset. Bootstrap sampling is available in sklearn.
P.S. You need to keep in mind that this solution is not optimal - best solution to this problem is to actually get more real data somehow.
Classification vs. Clustering
For author name disambiguation, I don't think you want clustering. What you want is classification.
You have a features for each author / publication. Now you give the classifier two of those feature vectors. It classifies "it is the same author" or "those are different authors".
Training / testing data
Having a binary classification problem, the testing suddenly becomes simple: Just use one of the measures used in literature so often (accuracy, precision, recall, confuscation matrix).
Getting the data might be a bit more complicated. You wrote that you have an XML file of 2000 records. I guess you can derive features from those records automatically and authors have an identifier? Then you can simply generate negative examples by having different authors and positive examples by checking if the identifier is the same.
Otherwise you can have a look at http://dblp.uni-trier.de/. Although there are likely many publications under the same author which should be different, they do distinguish authors not only by name but give them identifiers.
Alternatively, you can train a classifier to classify each of the known authors with e.g. > 30 publications. Then remove the softmax layer and use those features to distinguish the authors.
I have a question about this kind of situation.
If I have a black-box which contain only the code for one specific model,like Support Vector Machine,with no any other information in the box.
How should I test the model is still effective to use or not?
Thanks.
I would:
-first figure out if it works and how to train and generate predictions
-then pick a couple of datasets and divide it into your training and test data
-train and test the blackbox model and compare the results with a couple of known models
the point to stress here is to make sure you don't train your model(s) with your testing data...because that's the true test of how the model will generalize. If you're new to modelling, this is the most important thing.
It is common that certain models do well on some types of data and not others so that's the trick here...finding where the blackbox can be effective.
If your goal is to try and figure out the model in the box, then select datasets known to favour certain models and if it does well on it you can have an educated guess. But tricky to say for sure.
Not knowing the type of model is not good because it can be a time-waster if you are running a bunch of different algorithms on some data...you don't want to duplicate your efforts and it's nice to know how it can be regularized(unless it does that for you).