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https://issues.apache.org/jira/browse/SPARK-8518?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14634621#comment-14634621
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Meihua Wu commented on SPARK-8518:
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[~mengxr] [~yanboliang]
Sounds like to plan. We would start with something simple.

I agree that the Cox PH model is a non-parametric model. It is not easy to 
implement it efficiently in Spark: To determine the contribution of a 
particular row in the RDD to the objective function, you will need to reference 
to other rows in the RDD, effectively breaking the parallelism. 

The log-linear model of survival models are often called Accelerated Failure 
Time (AFT) model 
(https://en.wikipedia.org/wiki/Accelerated_failure_time_model). For AFT, there 
are again two favor: parametric vs non-parametric. For the parametric favor, 
the commonly used model is based on Weilbull / exponential distribution. Under 
these models, each row in the RDD contribute to the objective function 
independently, thus easily parallelizable. 



> Log-linear models for survival analysis
> ---------------------------------------
>
>                 Key: SPARK-8518
>                 URL: https://issues.apache.org/jira/browse/SPARK-8518
>             Project: Spark
>          Issue Type: New Feature
>          Components: ML
>            Reporter: Xiangrui Meng
>            Assignee: Yanbo Liang
>   Original Estimate: 168h
>  Remaining Estimate: 168h
>
> We want to add basic log-linear models for survival analysis. The 
> implementation should match the result from R's survival package 
> (http://cran.r-project.org/web/packages/survival/index.html).
> Design doc from [~yanboliang]: 
> https://docs.google.com/document/d/1fLtB0sqg2HlfqdrJlNHPhpfXO0Zb2_avZrxiVoPEs0E/pub



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