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### Is it a good practice to always scale/normalize data for machine learning? [duplicate]

My understanding is that when some features have different ranges in their values (for example, imagine one feature being the age of a person and another one being their salary in USD) will affect ...
43k views

### When should I apply feature scaling for my data [duplicate]

I had a discussion with a colleague and we started to wonder, when should one apply feature normalization / scaling to the data? Let's say we have a set of features with some of the features having a ...
52k views

### When to normalize data in regression? [duplicate]

Under what circumstances should the data be normalized/standardized when building a regression model. When i asked this question to a stats major, he gave me an ambiguous answer "depends on the data". ...
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### Do I need to standardize data before doing regression with python statsmodels.OLS [duplicate]

Sorry if this is a naive question. The independent variables are truly having different scale. They need to be standardized. The question is, does statsmodels.OLS do standardization for us as its ...
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### Why and When Do We Need Standardization for Machine Learning [duplicate]

When and why do we need standardization for machine learning? What's the benefit for doing so? For example, we replace $y_i$ with $(y_i - u_y)/ \sigma _y$ we also replace $x_i$ with \$x_ij - u_j / \...
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### Multicollinearity and centering [duplicate]

I read nearly all topics about collinearity but still have some questions... I know: multicollinearity is a problem because if two predictors measure approximately the same it is nearly impossible to ...
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### Normalization Interval variable [duplicate]

I have to perform a regression. My data set is composed of 12 independent(ration) variables and 1 dependent(interval) variable. After having performed a Normality test(kolmogorov-Smirnov) it resulted ...
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### Do I center an already transformed variable? [duplicate]

My chair would like me to center my data for my hierarchical multiple regression, including several moderators and interaction effects. It seems recommended to do this, if not to help minimize ...
518 views

### What are the pros and cons of standardizing variable in presence of an interaction? [duplicate]

I put this question because while reading the benefits of standardizing explanatory variables or not, I read good but contrasting opinions about standardizing when there are interaction in the model. ...
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### Normalization of 'change variables' in logistic regression [duplicate]

I am running a logit model trying to predict purchases on a dataset including change variables, i.e. I have a dataset of this kind: ...
183 views

### Why centering the data for machine-learning? [duplicate]

earners, I thought Friday was a good excuse to do a very basic question, which still makes me wonder. Why do we need the centering part in standard normalization? Assuming normalization means here, ...
120 views

### When to standardize data [duplicate]

I have a big dataset of sensor data (body temperature) acquired on a lot of people and each person is assessed for several days. ...
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### How do I know when to normalize my data or not for prediction purposes? [duplicate]

I have a dataset with 100 predictor variables (95 continuous, and 5 categorical) and 1 target variable (continuous). After plotting the density plots of the continuous predictor variables, they are ...