Split dataset to train and test for a LDA model - dataset

I have a dataset that contains about 17000 of user data scraped from twitter and I am working with the latent dirichlet allocation algorithm. I want to split my dataset but I am not sure what is the best way.
What are the criteria to split a dataset when it comes to train a LDA model.
I am using gensim to train LDA model.
Thank you

Related

How do I train model in Google NLP Sentiment Analysis correctly

I need to compare to sentiment models trained with different types of content. Google supplies you with a training dataset filled with tweets in a .csv file, As expected training with this went well however, when I decided to train a model using the Stanford NLP's dataset of IMDB reviews, I manage to upload the dataset without issue but when I train it the NLP, for some reason only predicts that the sentiment value is 2, regardless of what I write.
I figured that the dataset was diluted since, while there were 800-2000 examples of sentiment 0,1,3 and 4, there were 6000 examples of sentiment 2. Although after removing 4000 of these examples, the problem persisted.
I'm expecting my confusion matrix to not simply only have 100% prediction on each sentiment value. It should be distributed over the matrix w

multiple exponential and logarithmic regression (PYTHON)

I want to make data analysis. So, i searched and chose a dataset about automotive. Dataset includes 15 columns and 7500 rows. I used linear regression model(multiple) but now, i want to try another regression models like exponential and logarithmic. But i dont know how can i apply for 15 columns.
Can you lead about that ? Anyone has any idea? Firstable, i'll focus on the exponential regression.
Maybe, you can suggest a link or book or article about nonlinear regression models. (searched but i did not find exactly what i wanted)
Thank you for your interest.

What rule ILSVRC use to split into train and val datasets?

I am new to imagenet and the ILSVRC datasets.
In my previous studies, I often use k-fold validation to avoid overfitting, but it seem for the ILSVRC dataset, the train, val, test datasets are already split.
But I did not find any documents explaining how they split the datasets.
Is there any websites or paper for this question?
Thanks!
Training a deep neural network for image classification takes a lot of time. If your model trains for weeks you will not want to use k-fold cross validation.
See this link for a detailed description of train, validation and test datasets. For a good introduction to image classification with CNNs I also recommend you working through the whole course.

Neural network Dataset

I have been working on the neural network for that i need to train a data set in weka
but i dont have any data set to implement on weka can anyone help me in that
here is my paper in which im implementing
http://www.lcc.uma.es/~lfranco/A25-Gomez+Franco+09.pdf
Datasets are simple to create. All you need is to think of a scenario. For example, in a school, students would need to score 75 or higher in physical fitness test but this would vary according to weight and height. So your attributes in the table would be:
Weight - Height - Marks - Pass/Fail
Pass/Fail would be your Neural Net's label.

Datasets to test Nonlinear SVM

I'm implementing a nonlinear SVM and I want to test my implementation on a simple not linearly separable data. Google didn't help me find what I want. Can you please advise me where I can find such data. Or at least, how can I generate such data manually ?
Thanks,
Well, SVMs are two-class classifiers--i.e., these classifiers place data on either side of a single decision boundary.
Therefore, i would suggest a data set comprised of just two classes (that's not strictly necessary because of course an SVM can separate more than two classes by passing the Classifier multiple times (in series) over the data, it's cumbersome to do this during initial testing).
So for instance, you can use the iris data set, linked to in Scott's answer; it's comprised of three classes, Class I is linear separable from Class II and III; Class II and III are not linear separable. If you want to use this data set, for convenience-sake you might prefer to remove Class I (approx. the first 50 data rows), so what remains is a two-class system, in which the two remaining classes are not linearly separable.
The iris data set is quite small (150 x 4, or 50 rows/class x four features)--depending where you are with your SVM prototype testing, this might be exactly what you want, or you might want a larger data set.
An interesting family of data sets that are comprised of just two classes and that are definitely non-linearly separable are the the anonymized data sets supplied by the mega-dating site eHarmony (no affiliation of any kind). In addition to the iris data, I like to use these data sets for SVM prototype evaluation because they are large data sets with quite a few features yet still comprised of just two non-linearly separable classes.
I am aware of two places from which you can retrieve this data. The first Site has a single data set (PCI Code downloads, chapter9, matchmaker.csv) comprised of 500 data points (row) and six features (columns). Although this set is simpler to work with, the data is more or less in a 'raw' form and will require some processing before you can use it.
The second source for this data, contains two eHarmony data sets, one of them is comprised of over half million rows and 59 features. In addition, these two data sets have undergone substantial processing such that the only task required before feeding them to your SVM is routine rescaling of the features.
The particular data set you need will depend highly on your choice of kernel function, so It seems the easiest method is simply creating a toy data set yourself.
Some helpful ideas:
Concentric circles
Spiral-shaped classes
Nested banana-shaped classes
If you just want a random data set which is not linearly separable, may I suggest the Iris dataset? It is a multivariate data set where at least a couple of the classes in question are not linearly separable.
Hope this helps!
You can start with simple datasets like Iris or two-moons both of which are linearly non-separable. Once you are satisfied, you can move on to bigger datasets from the UCI ML repository, classification datasets.
Be sure to compare and benchmark against standard SVM solvers like libSVM and SVM-light.
If you program in Python, you can use a few functions in the package of sklearn.datasets.samples_generator to manully generate nested moon-shape data set, concentric circle data set etc. Here is a page of plots of these data sets.
And if you don't want to generate data set manually, you can refer to this website, where in the seciton of "shape sets", you can download these data set and test on them directly.

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