# Tagged Questions

78 views

### What is the time complexity of Lasso regression

What is the asymptotic time complexity of Lasso regression as either the number of rows or columns grows?
30 views

### Reducing data size to cross correlate with another data set?

I have three matrices A, B, C. A is a matrix of 200 X 32. There are 2000 such different A matrices which make up the B matrix. B is a matrix of 2000 x A. That is there are 2000 x 200 rows in matrix B ...
167 views

### Machine learning on big data: capability of generalization

I have being working applying different ML Algorithms oriented to Big Data and I have some open questions that I find interesting to think about. One of the first lectures about statistics begins ...
256 views

### Which machine learning algorithms can be scaled using hadoop/map-reduce

Scalable machine learning algorithms seem like the buzz these days. Every company is handling nothing short of big data. Is there a textbook which discusses what machine learning algorithms can be ...
82 views

### Machine learning for multi-level response

I have a dataset with ~90000 observations and less than 10 features (all continuous). The problem is that the response variable has ~300 categories. Currently I would try to fit a multinomial linear ...
181 views

### How to handle high dimensional feature vector in probability graph model?

I was doing some NLP related stuff which involves training a hidden Markov model, and use the model to segment sentences. For every sentence, I translate the tokens into feature vectors. The features ...
77 views

### what's the challenge in big data analysis? [closed]

Could you guys give me a review on the challenges and common techniques in dealing with big data problem? For example, what I know is that in when sample size is limited and dimension is high, the ...
61 views

### How to find important features in this problem

I was just thinking how ML techniques can be applied in the retail industry. Suppose we have data from a retailer who deals with apparel and cloth in this format and for each item there are ...
240 views

### Polynomial regression using scikit-learn

I am trying to use scikit-learn for polynomial regression. From what I read polynomial regression is a special case of linear regression. I was hopping that maybe one of scikit's generalized linear ...
218 views

### Test for linear separability

Is there a way to test linear separability of a two-class dataset in high dimensions? My feature vectors are 40-long. I know I can always run logistic regression experiments and determine hitrate vs ...
305 views

### Algorithm for price optimization [closed]

I'm trying to figure out a way for calculating price optimization in a commerce environment. In other words, I'm trying to analyze how a company can increase revenue and profitability by analyzing ...
607 views

### k-fold cross-validation strategy for large data set in statistical learning

I'm trying to learn the Bayesian network structure from a very large data set, and the R package I used for learning can only handle a very small portion of the data set (~10%) at one time due to the ...
144 views

### What are Effective Regression Techniques for Linguistic Analysis of Linked Data?

Cross-post from MathOverflow where it was suggested that I might get better results here. I am in the early stages of a problem that involves parsing a large number ($\approx 5 \times 10^9$) of ...
380 views

### Hybrid (K-means + Hierarchical ) clustering

I have a huge dataset (50,000 2000-dimensional sparse feature vectors). I want to cluster them in to k (unknown)clusters. As hierarchical clustering is very expensive in terms of time complexity ...
666 views

### Gaussian Process regression for high dimensional data sets

Just wanted to see if anyone has any experience applying Gaussian process regression (GPR) to high dimensional data sets. I'm looking into some of the various sparse GPR methods (e.g. sparse ...
191 views

### What software (paid or free) exists for learning large datasets?

Is there available software (or even just relevant papers) that can perform multiclass learning on datasets of 200m+ samples with 50+ classes and 1000+ features? What are the limits on dataset sizes ...
612 views

### First step for big data ($N = 10^{10}$, $p = 2000$)

Suppose you are analyzing a huge data set at the tune of billions of observations per day, where each observation has a couple thousand sparse and possibly redundant numerical and categorial ...
367 views

### Divide-and-conquer approach for hierarchical clustering

I have a huge data set (33K), each represented as a bit-vector of 275-dimensions. basically my data set can be represented as a 33000 x 275 matrix. I want to cluster these bit-vectors. I have tried ...
290 views

### Dealing with very large time-series datasets

I have access to a very large dataset. The data is from MEG recordings of people listening to musical excerpts, from one of four genres. The data is as follows: 6 Subjects 3 Experimental repetitions ...
217 views

### Learning on huge datasets

Basically, there are two common ways to learn against huge datasets (when you're confronted by time/space restrictions): Cheating :) - use just a "manageable" subset for training. The loss of ...
389 views

### How to decrease training set size?

I have a large training set, and it is too big to apply some algorithms due to computation limits. What are the common methods to decrease training set size without losing significant amount of ...
2k views

### How to quickly select important variables from a very large dataset?

I have a dataset with about 2,000 binary variables/200,000 rows and I'm trying to predict a single binary dependent variable. My chief goal at this stage isn't getting accuracy of prediction, but ...