Hi, I’m Oscar H. L. Henrichs, I’m a student at Pontifícia Universidade Católica do Paraná - Brazil, and I’ve been studying and implementing an study on Data Streams using Apache Samoa, under the supervision of Jean Paul Barddal. Our initial goal is to test and validate the benefits of using Apache Samoa, when comparing it with MOA and Spark.
So far we locally tested a few of the main learners of Apache Samoa, but we had some trouble when using NaiveBayes, Boosting and AdaptiveBoosting. We are not sure if the issues raised below have been solved in the new release, so we believe this is worthy of bringing up. With NaïveBayes, we think the problem is the implementation of LocalLearner, as the LocalLearner files seems incomplete or not extending the classes it should. For instance, we are trying to run the following snippet, but it fails: Comand: $ bin/samoa local target/SAMOA-Local-0.5.0-incubating-SNAPSHOT.jar "PrequentialEvaluation -l classifiers.NaiveBayes -s (ArffFileStream -f ARFFFfile/With_Change/SEA_wch_500k.arff) -f 100000" Error: "... Caused by: java.lang.Exception: Class named 'classifiers.NaiveBayes' is not an instance of org.apache.samoa.learners.Learner ...".*It's just a cut of the full error log. I've annexed the full log in the email. As for the Boosting I believe that I do not know how to call it properly, as it seems as it is really close to the Bagging process, but with a few extra steps that either it’s not defined or not properly called. This is the command we are trying to run, but again, it fails: Comand: $ bin/samoa local target/SAMOA-Local-0.5.0-incubating-SNAPSHOT.jar "PrequentialEvaluation -l classifiers.NaiveBayes -s (ArffFileStream -f ARFFFfile/With_Change/SEA_wch_500k.arff) -f 100000" Error: "Successfully instantiating org.apache.samoa.tasks.PrequentialEvaluation Exception in thread "main" java.lang.NullPointerException at org.apache.samoa.learners.classifiers.ensemble.BaggingDistributorProcessor.process(BaggingDistributorProcessor.java:63) at org.apache.samoa.topology.impl.SimpleProcessingItem.processEvent(SimpleProcessingItem.java:84) at org.apache.samoa.topology.impl.SimpleStream.put(SimpleStream.java:72) at org.apache.samoa.topology.impl.SimpleStream.put(SimpleStream.java:61) at org.apache.samoa.topology.LocalEntranceProcessingItem.injectNextEvent(LocalEntranceProcessingItem.java:45) at org.apache.samoa.topology.LocalEntranceProcessingItem.startSendingEvents(LocalEntranceProcessingItem.java:63) at org.apache.samoa.topology.impl.SimpleTopology.run(SimpleTopology.java:44) at org.apache.samoa.topology.impl.SimpleEngine.submitTopology(SimpleEngine.java:33) at org.apache.samoa.LocalDoTask.main(LocalDoTask.java:88) Process finished with exit code 1" As for, we’re sending you this e-mail because we need help to figure out how to resolve this issues in order to run those tasks. Sincerely, Oscar Henrichs
Naive_Bayes_Log.docx
Description: Naive_Bayes_Log.docx
