0
votes
0answers
5 views

Bi-normal separation feature selection (BNS) in R

I'm doing binary classification on highly dimensional text data, with a biased class distribution. After reading this paper, i found out about BNS feature selection. Is there any package that ...
0
votes
0answers
25 views

Is subtracting the mean from PCA necessary when using an SVD result that is feature scaled?

I've applied SVD to the original data matrix and eliminated insignificant columns and rows from U and V^T respectively using the Sigma values. I multiplied together my optimized U, Sigma, and V^T ...
0
votes
0answers
24 views

Feature selection from wavelet transformation in R

I am new to wavelets. Currently, I am developing a prediction model using time series data. I am using the wavelets package in R. I am taking part of the time ...
1
vote
1answer
58 views

Number of components in PCA

I believe I have a problem understanding PCA: I would like to use this technique to reduce the number of features of my problem. I originally have 10,000 features and 500 samples. However, the use of ...
1
vote
0answers
71 views

Feature extraction for customer churn data

I have a customer churn data, and would be implementing algorithms (decision tree, logistic regression, segment analysis). I have doubt on feature extraction procedure though. The training sample has ...
2
votes
1answer
37 views

Selecting features manually and proving the rest are redundant

I'm working with a gesture dataset, where each gesture has a variable number of frames, and each frame has the 3d position of 20 joints, so that each gesture is represented by a matrix of size frames ...
0
votes
1answer
77 views

Identify original features corresponding to high singular/principal component values [duplicate]

In MATLAB, while SVD gives a diagonal matrix S of decreasing singular values, PCA gives a column vector LATENT of decreasing principal component values. How can S be used to obtain a subset of ...
0
votes
0answers
11 views

Error trying to reduce my data dimentions [duplicate]

I'm trying to produce a linear regression model, but I only have 25 observations and 34 predictors. I'm trying feature selection, ...
3
votes
2answers
77 views

Advice for interpolating a model

I'm new in Stack Exchange, so I hope no to be off topic. I'm also new in bioinformatics and I was asked to perform an analysis. Briefly, I have a dataset of 29 cell lines and the IC50 values of a test ...
1
vote
1answer
153 views

Using principal component analysis (PCA) for feature selection in regression [duplicate]

I have a dataset $D$ made of $m$ samples and $n$ features with $n \gg m$. For each sample I have a score $s$ which I would like to be able to predict. As the number of features is very high (compared ...
0
votes
0answers
83 views

equivalent of PCA explained variance ratio for SVD ?

i am wondering if there is an equivalent of PCA explained variance ratio for SVD. What are the measures I can get to monitor the number of columns I keep after the SVD ? Are any of these metrics ...
2
votes
0answers
75 views

Confusion related to feature selection

Well my objective is to predict solar energy radiation at a particular location given some features like wind, temperature, humidity ... I have a total data for 10 years where I have the measurement ...
11
votes
5answers
396 views

What can cause PCA to worsen results of a classifier?

I have a classifier that I'm doing cross-validation on, along with a hundred or so features that I'm doing forward selection on to find optimal combinations of features. I also compare this against ...
3
votes
0answers
174 views

Sensible to include ratio as a variable in logistic regression?

I'm creating a generalised linear regression using a binomial link function for two variables A and B. From looking at the data it appears that A/B may have discriminatory effect. Is it sensible to ...
17
votes
5answers
3k views

Detecting significant predictors out of 300 independent variables

In a dataset of two non-overlapping populations (patients & healthy, total $n=60$) I would like to find (out of $300$ independent variables) significant predictors for a continuous dependent ...
7
votes
2answers
5k views

Using principal component analysis (PCA) for feature selection

I'm new to feature selection and I was wondering how you would use PCA to perform feature selection. Does PCA compute a relative score for each input variable that you can use to filter out ...
3
votes
4answers
793 views

How to know when to stop reducing dimensions with PCA?

I'm using PCA to reduce dimensionality before I feed the data into a classifier. My bootstrap/cross-validation has shown a significant reduction in test error as a result of applying PCA and keeping ...
1
vote
3answers
2k views

Use of PCA analysis to select variables for a regression analysis

I have too many environmental variables to use in a multiple regression analysis. If I use all the variables the models are just too complex. The use of the PCA axes in the regression analysis was ...
1
vote
2answers
1k views

How to integrate principal components with GLM?

How would I integrate the output of a principal components analysis with a GLM (assuming the PCA is used for variable selection for the GLM)?
3
votes
1answer
450 views

Which are the most effective methods for selecting independent variables?

Some clustering algorithms require independence of variables but (especially working with real data) variables are often highly correlated. I have been suggested to apply a Principal Component ...
5
votes
2answers
824 views

Is it possible to use kernel PCA for feature selection?

Is it possible to use kernel principal component analysis (kPCA) for Latent Semantic Indexing (LSI) in the same way as PCA is used? I perform LSI in R using the prcomp PCA function and extract the ...