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Questions tagged [som]

A self-organizing map (SOM) is a type of artificial neural network that is trained using unsupervised learning to produce a map reprensenting the input space of the training samples.

A self-organizing map (SOM) is a type of artificial neural network that is trained using unsupervised learning to produce a map representing the input space of the training samples. Also, some supervised and semi-supervised SOMs exist.

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How to map/plot new data onto a trained SOM map?

After training a SOM, how can you plot new data onto the SOM and visualise how it maps onto the SOM? Ideally, I would like for it to be plotted with the corresponding classification colour and node location. identify() has the capability of…
Spencer Trinh
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Self-Organizing Maps (SOM) problem in MATLAB

I have a text file that include data. My text file: young, myopic, no, reduced, no young, myopic, no, normal, soft young, myopic, yes, reduced, no young, myopic, yes, normal, hard young, hyperopia, no, reduced, no young, hyperopia, no, normal,…
Serdar Demir
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How can I use SOM algorithm for classification prediction

I would like to see If SOM algorithm can be used for classification prediction. I used to code below but I see that the classification results are far from being right. For example, In the test dataset, I get a lot more than just the 3 values that I…
mql4beginner
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Clustering using SOM in python

I am trying to perform test summarize using self organizing map (SOM) as the clustering model. Do we have any libraries for performing SOM in python.
Koteswara
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Is dimensionality reduction reversible?

I have implemented a dimentionality reduction algorithm using ENCOG, that takes a dataset (call it A) with multiple features and reduces it to a dataset (B) with only one feature (I need that for time series analisys). Now my question is, I have a…
Corneliu Maftuleac
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Kohonen SOM Maps: Normalizing the input with unknown range

According to "Introduction to Neural Networks with Java By Jeff Heaton", the input to the Kohonen neural network must be the values between -1 and 1. It is possible to normalize inputs where the range is known beforehand: For instance RGB (125, 125,…
S.N
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how to display som map with rshiny

I'm trying to implement som map with rshiny in rstudio , so I have this function : som(data,code , 6,6, init="linear", alpha=c(0.05,0.01), alphaType="inverse", neigh="gaussian", topol="hexa", radius=NULL, rlen=1000, err.radius=1, …
user3603831
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Labelling a plotmap of self organizing map in Matlab(edited)

I want to label the plothitmap plotsomhits(net,inputs) of the iris dataset found in the neural network toolbox. How would I do that. I want the class labels to be superimposed on the plothitmap. Any ideas?It would look something like this: Is it…
motiur
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Formulation of the U-matrix (unified distance matrix) as a matrix operation?

I am computing the u-matrix in parallel, and am concerned with the computational cost of traversing matrices in Python, as opposed to computing values by means of matrix operations using Numpy. When computing the u-matrix, you need the distance to…
user1603472
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Kohonen SOM Maps in R Tutorial

I am simply looking for a good tutorial that will walk me through how to create a SOM in R. I am reading Kohonen and Kaski's paper on using the maps to identify the structure of Welfare, and want to try the technique my self. I think many of the…
Btibert3
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How to train a SOM with multiple vectors of different length ? (Using R package kohonen or else)

I'm looking to train one self-organizing map on different trajectories which are basically data frames of different lengths. It works very well with one trajectory but it leads to massive overfitting and doesn't help to recognize different types of…
Baptiste Van Brandt
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How can I know which cluster of self-organizing map (SOM) an element belongs to in python?

I am new with clustering and neural nets, and I have just started using Self-Organizing Maps (SOM) to perform some clustering. I have a 15 dimensional dataset and I created a som with the next code: size = 20 from minisom import MiniSom som =…
jartymcfly
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R, SOM, Kohonen Package, Outlier Detection

With SOM I experimented a little. First I used MiniSOM in Python but I was not impressed and changed to the kohonen package in R, which offers more features than the previous one. Basically, I applied SOM for three use cases: (1) clustering in 2D…
Tamas
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how to visualize/plot SOM in python?

I want to create a map for my cluster result (this kind of map).For example, this is the result that I generate using SOM. Example of my input (based on DNA sequence motif): motif 1 = 0.19,0.95,0.01,0,0.76,0,1.04,0,0,0.05,0,1,0,0,1,0 motif 2…
Alaska
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Activation function in self organizing map

What is the activation function used by self organizing map? Is it the same sigmoid or tansig activation.
user6460588
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