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Does lasso remove variables?
This actually already give us a hint that it might be necessary to remove some of the variables. Then, Lasso forces the coefficients of the variables towards zero. This is now the process of shrinkage. This is to make the model less sensitive to the new data set.
The potential solutions include the following:
- Remove some of the highly correlated independent variables.
- Linearly combine the independent variables, such as adding them together.
- Perform an analysis designed for highly correlated variables, such as principal components analysis or partial least squares regression.
How to add correlated variables to LASSO model?
LARS Step 1 : Variable 1 added LARS Step 2 : Variable 2 added LARS Step 3 : Variable 4 added LARS Step 4 : Variable 3 added LARS Step 5 : Variable 5 added It adds both of the correlated variables to the model in the first two steps. This is the opposite from what I read in several papers.
Can a lasso be used to remove a variable?
In many analyses, some variables should be in the model REGARDLESS of any measure of significance. Sometimes they are necessary control variables. Other times, finding a small effect can be substantively important. LASSO encourages shrinking of coefficients to 0, i.e. dropping those variates from your model.
How does Lasso make sense to do OLS?
Often, LASSO will prefer the weak variable over the strong causal variable. Also, it may at times even cause to shift the directional signs of variables (shifting from one direction that makes sense to an opposite direction that does not).
Which is better, a relaxed lasso or a standard lasso?
There is a whole zoo of sparse learning methods though, most of which are better than LASSO. E.g. there is Meinhausen’s relaxed LASSO, adaptive LASSO and SCAD and MCP penalized regression as implemented in the ncvreg package, which all have less bias than standard LASSO and so are preferrable.