Questions tagged [feature-selection]
Methods and principles of selecting a subset of attributes for use in further modelling
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Metrics to evaluate features' importance in classification problem (with random forest)
I want to evaluate the importance of each of the features of a 2000x60 dataset in a classification problem with random forest.
The most widely used ones apparrently are:
Cross Entropy-Information ...
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0
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Multiple Hypothesis Testing in feature selection process
I am doing feature selection of features which are of binary nature i.e. each feature represents presence or absence of a substructure in a molecule. And I have a target variable of two classes. My ...
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1
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BorutaShap implementation
I want to use BorutaShap for feature selection in my model. I have my train_x as an numpy.ndarray and I want to pass it to the ...
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1
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How do feature selection on a sparse matrix?
Say I want to do features selection on a sparse matrix, i.e., 10,000 rows x 1500 features, but the matrix is mostly sparse. Let's say the features are all numeric and the target is binary and discrete....
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Determine the most important documents for supervised learning
I have somewhat of a general/high level question.
Assume I'm doing supervised machine learning on some text data (tweets for example) and categorizing the documents to a certain taxonomy (multi-class ...
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Feature engineering: The more features I add the better RMSE I get?
I have a model with 7 features, I'm trying to figure out if I can improve the performance of this model by adding additional features. So I'm relying on the RMSE to measure the accuracy of my ...
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Is there a standard data science workflow/decision tree?
I'm looking for some kind of reference that essentially shows an example of an entire data analysis workflow beginning with feature engineering, and ending with analyzing the results.
I know the ...
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Feature engineering before splitting
This is a sister post to the original closed post (here). Since the data transformation part is done after data spliting on the TRAINING data only, I wonder wouldn't such transformation has dependency ...
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Change feature importance in a trained model
I am giving a toy example for describing a real world business problem. Let's say I am a publisher and I have some book stores to visit. By visiting those stores I will check whether they have ...
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Feature selection: ANOVA between features vs within a feature
I am currently performing feature selection on a dataset containing continuous and categorical features. The target is a continuous variable.
If I understand properly, ANOVA can be used between ...
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Feature selection on datasets with both categorical and numerical features
I'm proposing a novel methodology for feature selection in the context of tabular datasets that contain both numerical and categorical features. In order to prove the efficacy of my methodology, I ...
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1
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Information Gain & Gini Index for NLP
I know how Information Gain and Gini Index work in General.
I have problem figuring out how to apply these techniques in NLP and text feature extraction.
Can someone show me an example of how to ...
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Creating a complex featureset for regression modeling
I am currently working a on project that requires me to convert all of the categorical variables to continuous (or binary) variables to build a regression model. The problem is that I have more than ...
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2
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Regression performance with Feature Selection
I would like to ask you a theoretical question. In my project I am trying to get a better performance from my regression model by feature selection methods, especially with CatBoost feature ...
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1
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Literature on selecting specific dimensions in a word embedding vector
I am aware that the different dimensions in the word embedding represents different information and algebraic operations can be performed between two embeddings for example.
Can anyone point me to ...
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1
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Why the order of the fearures affects synapse LightGBM predictions?
I am using LighGBM Classifier and Regressor and it seems that the order of the features I am adding, affect the predictions of the model. Everytime I change the order, another result comes up and with ...
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sklearn - OneHotEncoding and SelectPercintile
in sklearn example there is a code
...
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SelectKBest and Correlation returns me excatly same feature selection. How?
Im working on selecting most effective features from a dataset with over that 2000 features. Im using different algorithms for that (selectKBest with chi-square, Extra Trees, Correlation etc.) But ...
2
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1
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Logistic Regression Model for categorical features with multiple values in each category
I am working on an insurance use case to build a logistic regression classifier to predict if a policy will lapse or not. The dataset has more than 20 categorical features for a policy. Each ...
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1
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Correlation with target variable for regression problem
Given the following dataframe
age job salary
0 1 Doctor 100
1 2 Engineer 200
2 3 Lawyer 300
...
with ...
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2
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How many features do I select when doing feature selection for regression algorithms? Is R2 and RMSE good measures of success for overfitting?
Context: I'm currently crafting and comparing machine learning models to predict housing data. I have around 32000 data points, 42 features, and I'm predicting housing price. I'm comparing Random ...
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Does sklearn perform feature selection within cross validation?
I would like to add a feature selector on my pipeline and use gridsearchcv to tune both the hyperparameters of the selector and the classifier(s).
I am wondering if sklearn performs feature selection ...
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0
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Feature selection for siamese network
I have a regression problem for which two observations are compared by a siamese-like Multilayer Perceptron.
Each observation 'O' is described by a feature vector 'X' of a certain number 'N' of ...
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Feature importance has more variables than included in .csv?
I have a .csv dataset with 26 variables, ranging from Age to Weight and so forth. I plotted a feature importance plot with;
...
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Feature selection methods when input data is continuous but target variable is categorical
I plan on extracting features from a univariate time series, and use a feature selection method to select relevant features to predict a binary target variable via logistic regression. But, I have 2 ...
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1
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Should I get dummies and then look at multicollinearity?
I have data that includes continuous and categorical features. The task is regression and I am looking to remove features that are high correlated with other features (multicollinearity). To do this, ...
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Minimum number of features for Naïve Bayes model
I keep on reading that Naive Bayes needs fewer features than many other ML algorithms. But what's the minimum number of features you actually need to get good results (90% accuracy) with a Naive Bayes ...
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1
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How to use hierarchical variable in a ML model
I am working on a binary classification problem with 1000 rows and 20 variables.
I have variables like product_id, city, ...
2
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1
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Is there a way to output feature importance based on the outputted class?
I'm running a random forest classifier in Python (two classes). I am using the feature_importances_ method of the ...
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1
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196
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Percentage of missing values so that we can't perform imputation
(This is not a question on ways to handle missing data)
I have a dataset with around $80$ or so features and around $100000$ rows. Several of those features have missing (NULL) values for a "large ...
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How is it called when instead of creating predective models finding patterns in observed data (ML) you tried to guess the model theorically...?
I'm a college student appasionated of machine learning and I've decided to my bachelor thesis about it. I thought that as an interesting introduction to machine learning, I could introduce it by ...
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How to interpret a specific feature importance?
Apologies for a very case specific question. I have a dataset of genes, with which I am using machine learning to predict if a gene causes a disease. One of the features I have is a beta value (which ...
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1
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Redundant feature after one hot encoding
I have a numerical feature called $x$ and a categorical feature called $y$.
$y$ is an ordinal feature (A,B,C,D,E,F).
I am using label encoding for my y feature and when I am seeing the correlation ...
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Rapidminer and decision tree weights
In Rapidminer, are the decision tree's weights a measure of the "importance" of attributes in the splitting procedure ?
If yes, why is useful to know these weights ?
Are there better methods to know ...
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How can I reduce the number of dimensions using a Clustering algorithm in a mixed dataset?
I am working with a mixed data set, corresponding to TV consumption data, with the aim of reducing the number of features to only those relevant to detect TV consumption patterns (or consumption ...
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1
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Variance threshold with python problem
i’am a beginner in scikit-learn and i’ve a little problem when using feature selection module VarianceThreshold, the problem is when i set the variance ...
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3
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How can we shorten our questionnaire to only ask the most informative question at each point?
Our product has an onboarding questionnaire which asks the same 58 questions (with numeric answers) to every new user. That’s a lot of questions, so we’d love to reduce the number of questions we ask ...
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Queries regarding feature importance for categorical features
Queries regarding feature importance for categorical features:
Context:
I have almost 185 categorical features and these categorical features have either 2 or 3 or 8 or 1 or sometimes 4 categories, ...
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1
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How should I engineer features for Named Entity Identification task?
I was working on Named Entity Identification (not recognition) task. In this NLP task, given a sentence, model has to predict whether each word (aka token) is named entity or not. The dataset used ...
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1
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Feature selection for propensity model
I'm trying to build a propensity model for whether or not a customer will buy a second product. I was given data that looks like this:
| Age | Income | DaysSince1stPurchase | Bought2ndProduct |
|:---- ...
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How to represent facial features from video and classify high/low personality traits from facial features?
The dataset has 3-minute 30fps video conversations (no audio) of 150 extroverted and 150 introverted individuals. The goal is to classify them as "introverts" or "extroverts" based ...
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how to test if labels have actual dependencies on features?
I am trying to train an LSTM(many to one) model with multivariate time series input and a categorical output.
after training for quite some time, the resulting model still has low accuracy and high ...
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Simultaneous Feature Selection and Time Series Selection
I have about 2000 features and 14 times series for them to predict. I am trying to reduce my feature count, but also my time series count. The goal is to find the 30 core features best at predicting ...
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1
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Brute-force feature selection and cross-validation
There is an existing score made of 10 parameters; each parameter is equally weighted & the total score is found by summing the score for each parameter.
I want to try to reduce the number of ...
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1
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Using cross validation score to perform feature selection
So to perform my feature selection I ran cross validation over and over again, each time trying different subsets of my attributes and repeated this until I got the best cross validation score I could ...
2
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1
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scikit-learn OMP mem error
I tried to use OMP algorithm available in scikit-learn. My net datasize which includes both target signal and dictionary ~ 1G. However when I ran the code, it exited with mem-error.
The machine has ...
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How to use scikit-learn to extract features from text when I only have positive and unlabeled data?
I'm looking for something similar to this
https://scikit-learn.org/stable/auto_examples/text/plot_document_classification_20newsgroups.html#sphx-glr-auto-examples-text-plot-document-classification-...
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Feature Selection on Aggregated Targetdata
I have a question about feature selection on a dataset where the target variable is aggregated by the sum of different data points. I want to predict the number of sales depending on a variety of ...
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Why is the feature direction chosen in the direction associated with largest eigenvalue of $Σ_T$ in case of more than two classes?
Why is the feature direction chosen in the direction associated with largest eigenvalue of $Σ_T$ in case of more than two classes? Please see the following.
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Feature importance in neural networks
Hello I am using keras to develop a neural network model and I have a data of 45 numerical predictor variables, 2 categorical targets that will be predicted each with a different model. As I found, ...