Sometimes performing feature reduction reduces number of features with methods like PCA and then we could scale only the relevant variables. Is there a rule that we need to do normalization/scaling first and then the feature reduction?
Should we always first perform feature normalization and then the feature reduction?
700 views Asked by Sharat Ainapur At
1
There are 1 answers
Related Questions in MACHINE-LEARNING
- C++ using std::vector across boundaries
- Linked list without struct
- Connecting Signal QML to C++ (Qt5)
- how to get the reference of struct soap inherited in C++ Proxy/Service class
- Why we can't assign value to pointer
- Conversion of objects in c++
- shared_ptr: "is not a type" error
- C++ template using pointer and non pointer arguments in a QVector
- C++ SFML 2.2 vectors
- Lifetime of temporary objects
Related Questions in DATA-SCIENCE
- C++ using std::vector across boundaries
- Linked list without struct
- Connecting Signal QML to C++ (Qt5)
- how to get the reference of struct soap inherited in C++ Proxy/Service class
- Why we can't assign value to pointer
- Conversion of objects in c++
- shared_ptr: "is not a type" error
- C++ template using pointer and non pointer arguments in a QVector
- C++ SFML 2.2 vectors
- Lifetime of temporary objects
Related Questions in FEATURE-ENGINEERING
- C++ using std::vector across boundaries
- Linked list without struct
- Connecting Signal QML to C++ (Qt5)
- how to get the reference of struct soap inherited in C++ Proxy/Service class
- Why we can't assign value to pointer
- Conversion of objects in c++
- shared_ptr: "is not a type" error
- C++ template using pointer and non pointer arguments in a QVector
- C++ SFML 2.2 vectors
- Lifetime of temporary objects
Related Questions in MACHINE-LEARNING-MODEL
- C++ using std::vector across boundaries
- Linked list without struct
- Connecting Signal QML to C++ (Qt5)
- how to get the reference of struct soap inherited in C++ Proxy/Service class
- Why we can't assign value to pointer
- Conversion of objects in c++
- shared_ptr: "is not a type" error
- C++ template using pointer and non pointer arguments in a QVector
- C++ SFML 2.2 vectors
- Lifetime of temporary objects
Related Questions in FEATURE-SCALING
- C++ using std::vector across boundaries
- Linked list without struct
- Connecting Signal QML to C++ (Qt5)
- how to get the reference of struct soap inherited in C++ Proxy/Service class
- Why we can't assign value to pointer
- Conversion of objects in c++
- shared_ptr: "is not a type" error
- C++ template using pointer and non pointer arguments in a QVector
- C++ SFML 2.2 vectors
- Lifetime of temporary objects
Popular Questions
- How do I undo the most recent local commits in Git?
- How can I remove a specific item from an array in JavaScript?
- How do I delete a Git branch locally and remotely?
- Find all files containing a specific text (string) on Linux?
- How do I revert a Git repository to a previous commit?
- How do I create an HTML button that acts like a link?
- How do I check out a remote Git branch?
- How do I force "git pull" to overwrite local files?
- How do I list all files of a directory?
- How to check whether a string contains a substring in JavaScript?
- How do I redirect to another webpage?
- How can I iterate over rows in a Pandas DataFrame?
- How do I convert a String to an int in Java?
- Does Python have a string 'contains' substring method?
- How do I check if a string contains a specific word?
Popular Tags
Trending Questions
- UIImageView Frame Doesn't Reflect Constraints
- Is it possible to use adb commands to click on a view by finding its ID?
- How to create a new web character symbol recognizable by html/javascript?
- Why isn't my CSS3 animation smooth in Google Chrome (but very smooth on other browsers)?
- Heap Gives Page Fault
- Connect ffmpeg to Visual Studio 2008
- Both Object- and ValueAnimator jumps when Duration is set above API LvL 24
- How to avoid default initialization of objects in std::vector?
- second argument of the command line arguments in a format other than char** argv or char* argv[]
- How to improve efficiency of algorithm which generates next lexicographic permutation?
- Navigating to the another actvity app getting crash in android
- How to read the particular message format in android and store in sqlite database?
- Resetting inventory status after order is cancelled
- Efficiently compute powers of X in SSE/AVX
- Insert into an external database using ajax and php : POST 500 (Internal Server Error)
I would suggest first do your normalization/scaling on your feature data and then performing feature selection. This is because most of the feature selection techniques require a meaningful representation of your data. By normalizing your data your features have the same order of magnitude and scatter, which makes it easier to find which one of those is more relevant.
For example, for PCA the computation is based on the standard deviation (SD) of your features to find the relevant axis of a new projection of your data. If you do not normalize your data, features with a high SD will have a higher weight compared to features with a small SD distorting their relevance when computing the PCA.