Hi,

Wonderful. I was sampling the output, but with a bug. Your comment brought
the realization :). I was indeed victimized by the complete separability
issue :).

Thanks a lot.
with regards,
Nikhil

On Tue, Nov 17, 2015 at 5:26 PM, DB Tsai <dbt...@dbtsai.com> wrote:

> How do you compute the probability given the weights? Also, given a
> probability, you need to sample positive and negative based on the
> probability, and how do you do this? I'm pretty sure that the LoR will
> give you correct weights, and please see the
> generateMultinomialLogisticInput  in
>
> https://github.com/apache/spark/blob/master/mllib/src/test/scala/org/apache/spark/mllib/classification/LogisticRegressionSuite.scala
>
> Sincerely,
>
> DB Tsai
> ----------------------------------------------------------
> Web: https://www.dbtsai.com
> PGP Key ID: 0xAF08DF8D
>
>
> On Tue, Nov 17, 2015 at 4:11 PM, njoshi <nikhil.jo...@teamaol.com> wrote:
> > I am testing the LogisticRegression performance on a synthetically
> generated
> > data. The weights I have as input are
> >
> >    w = [2, 3, 4]
> >
> > with no intercept and three features. After training on 1000
> synthetically
> > generated datapoint assuming random normal distribution for each, the
> Spark
> > LogisticRegression model I obtain has weights as
> >
> >  [6.005520656096823,9.35980263762698,12.203400879214152]
> >
> > I can see that each weight is scaled by a factor close to '3' w.r.t. the
> > original values. I am unable to guess the reason behind this. The code is
> > simple enough as
> >
> >
> > /*
> >  * Logistic Regression model
> >  */
> > val lr = new LogisticRegression()
> >   .setMaxIter(50)
> >   .setRegParam(0.001)
> >   .setElasticNetParam(0.95)
> >   .setFitIntercept(false)
> >
> > val lrModel = lr.fit(trainingData)
> >
> >
> > println(s"${lrModel.weights}")
> >
> >
> >
> > I would greatly appreciate if someone could shed some light on what's
> fishy
> > here.
> >
> > with kind regards, Nikhil
> >
> >
> >
> >
> > --
> > View this message in context:
> http://apache-spark-user-list.1001560.n3.nabble.com/Spark-LogisticRegression-returns-scaled-coefficients-tp25405.html
> > Sent from the Apache Spark User List mailing list archive at Nabble.com.
> >
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>



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