[ 
https://issues.apache.org/jira/browse/LUCENE-8647?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16745452#comment-16745452
 ] 

Sambhav Kothari edited comment on LUCENE-8647 at 1/17/19 8:04 PM:
------------------------------------------------------------------

Example implementation of a possibly useful subclass in contrib/ltr  -

 

 
{code:java}
/**
 * A special explanation class that stores feature scores for a specific doc 
that a model is scoring.
 */
public class ModelExplanation extends Explanation {

  private Map<String, Float> featureImportance = new HashMap<>();
  private Map<String, Float> featureValues = new HashMap<>();

  public Map<String, Float> getFeatureImportance() {
    return featureImportance;
  }

  public void setFeatureImportance(Map<String, Float> featureImportance) {
    this.featureImportance = featureImportance;
  }

  public Map<String, Float> getFeatureValues() {
    return featureValues;
  }

  public void setFeatureValues(Map<String, Float> featureValues) {
    this.featureValues = featureValues;
  }

  @Override
  public LinkedHashMap<String, Object> toMap() {
    LinkedHashMap<String, Object> data = super.toMap();
    data.put("featureImportance", getFeatureImportance());
    data.put("featureValues", getFeatureValues());
    return data;
  }
}
{code}
 


was (Author: samj1912):
Example implementation of a subclass -

 

 
{code:java}
/**
 * A special explanation class that stores feature scores for a specific doc 
that a model is scoring.
 */
public class ModelExplanation extends Explanation {

  private Map<String, Float> featureImportance = new HashMap<>();
  private Map<String, Float> featureValues = new HashMap<>();

  public Map<String, Float> getFeatureImportance() {
    return featureImportance;
  }

  public void setFeatureImportance(Map<String, Float> featureImportance) {
    this.featureImportance = featureImportance;
  }

  public Map<String, Float> getFeatureValues() {
    return featureValues;
  }

  public void setFeatureValues(Map<String, Float> featureValues) {
    this.featureValues = featureValues;
  }

  @Override
  public LinkedHashMap<String, Object> toMap() {
    LinkedHashMap<String, Object> data = super.toMap();
    data.put("featureImportance", getFeatureImportance());
    data.put("featureValues", getFeatureValues());
    return data;
  }
}
{code}
 

> Create a generic method in the Explanation class to get explanation attributes
> ------------------------------------------------------------------------------
>
>                 Key: LUCENE-8647
>                 URL: https://issues.apache.org/jira/browse/LUCENE-8647
>             Project: Lucene - Core
>          Issue Type: Improvement
>          Components: core/search
>    Affects Versions: 7.5
>            Reporter: Sambhav Kothari
>            Priority: Minor
>
> Initial proposal and discussion can be found here - 
>  
> [http://mail-archives.apache.org/mod_mbox/lucene-java-user/201901.mbox/%3CCADitDkmnv4Vup5VG2ZwLUOv5VM=itu-y8eugxxmtoppzpcy...@mail.gmail.com%3E]
>  
> Currently the Explanation class has a toString method, but it doesn't seem to 
> have any method to output the explanation as a NamedList. Part of the reason 
> is that NamedList is a Solr only concept and it cannot exist in lucene. But 
> this leads to utility functions like 
> ([https://github.com/apache/lucene-solr/blob/1d85cd783863f75cea133fb9c452302214165a4d/solr/core/src/java/org/apache/solr/response/transform/ExplainAugmenterFactory.java#L115]
>  and 
> [https://github.com/apache/lucene-solr/blob/1d85cd783863f75cea133fb9c452302214165a4d/solr/core/src/java/org/apache/solr/util/SolrPluginUtils.java#L400-L466]
>  which assume a particular structure about explanations.
>  
> Explanation should instead have a toMap method which returns a Map of 
> key-value pairs which can then be converted to a NamedList in Solr. This can 
> be exceptionally useful if we have a class inheriting from Explanation that 
> adds more attributes.
>  
> For example for Learning to Rank model explanations we can have a 
> ModelExplanation class which adds doc-specific feature scores and other 
> machine learning model explanations to the output. It also allows the 
> ExplainAugmenter and other classes to have a more generic way of getting an 
> Explanation's data in a structured format.
>  
> The way it currently does so is very ugly - 
> [https://github.com/apache/lucene-solr/blob/1d85cd783863f75cea133fb9c452302214165a4d/solr/core/src/java/org/apache/solr/response/transform/ExplainAugmenterFactory.java#L115]
>  
> This also implies that we shouldn't keep Explanation as a final class 
> anymore. Storing and parsing things like feature values in the explanation 
> description doesn't seem like the right way.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

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

Reply via email to