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https://issues.apache.org/jira/browse/SPARK-8522?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14601669#comment-14601669
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Apache Spark commented on SPARK-8522:
-------------------------------------

User 'holdenk' has created a pull request for this issue:
https://github.com/apache/spark/pull/7024

> Disable feature scaling in Linear and Logistic Regression
> ---------------------------------------------------------
>
>                 Key: SPARK-8522
>                 URL: https://issues.apache.org/jira/browse/SPARK-8522
>             Project: Spark
>          Issue Type: New Feature
>          Components: ML
>            Reporter: DB Tsai
>            Assignee: holdenk
>
> All compressed sensing applications, and some of the regression use-cases 
> will have better result by turning the feature scaling off. However, if we 
> implement this naively by training the dataset without doing any 
> standardization, the rate of convergency will not be good. This can be 
> implemented by still standardizing the training dataset but we penalize each 
> component differently to get effectively the same objective function but a 
> better numerical problem. As a result, for those columns with high variances, 
> they will be penalized less, and vice versa. Without this, since all the 
> features are standardized, so they will be penalized the same.
> In R, there is an option for this.
> `standardize` 
> Logical flag for x variable standardization, prior to fitting the model 
> sequence. The coefficients are always returned on the original scale. Default 
> is standardize=TRUE. If variables are in the same units already, you might 
> not wish to standardize. See details below for y standardization with 
> family="gaussian".



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