Dev Lakhani created SPARK-5273:
----------------------------------

             Summary: Improve documentation examples for LinearRegression 
                 Key: SPARK-5273
                 URL: https://issues.apache.org/jira/browse/SPARK-5273
             Project: Spark
          Issue Type: Improvement
          Components: Documentation
            Reporter: Dev Lakhani
            Priority: Minor


In the document:
https://spark.apache.org/docs/1.1.1/mllib-linear-methods.html

Under
Linear least squares, Lasso, and ridge regression

The suggested method to use LinearRegressionWithSGD.train()
// Building the model
val numIterations = 100
val model = LinearRegressionWithSGD.train(parsedData, numIterations)

is not ideal even for simple examples such as y=x. This should be replaced with 
more real world parameters with step size:

val lr = new LinearRegressionWithSGD()
lr.optimizer.setStepSize(0.00000001)
lr.optimizer.setNumIterations(100)

or

LinearRegressionWithSGD.train(input,100,0.00000001)

To create a reasonable MSE. It took me a while using the dev forum to learn 
that the step size should be really small. Might help save someone the same 
effort when learning mllib.





--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org

Reply via email to