You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@datafu.apache.org by "Matthew Hayes (JIRA)" <ji...@apache.org> on 2014/08/23 16:24:10 UTC

[jira] [Commented] (DATAFU-60) Support NDCG calculation within a UDF

    [ https://issues.apache.org/jira/browse/DATAFU-60?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14108012#comment-14108012 ] 

Matthew Hayes commented on DATAFU-60:
-------------------------------------

Tried running TestRange tests and I saw a failure:

{code}
PASSED: testFloatingBuckets
PASSED: testIntegerBuckets
PASSED: testMalformedBuckets1
PASSED: testMalformedBuckets2
PASSED: testNegInfinity
PASSED: testScientificBuckets
FAILED: testInfinity
{code}

> Support NDCG calculation within a UDF
> -------------------------------------
>
>                 Key: DATAFU-60
>                 URL: https://issues.apache.org/jira/browse/DATAFU-60
>             Project: DataFu
>          Issue Type: New Feature
>            Reporter: Joshua Hartman
>              Labels: features
>         Attachments: DATAFU-60-v2.patch, DATAFU-60.patch
>
>   Original Estimate: 48h
>  Remaining Estimate: 48h
>
> Ndcg is a common evaluation metric for the quality of a list of items presented to a user. It is an especially common metric used in the search literature.
> This feature request is to implement a udf to calculate ndcg. 
> NDCG can be calculated using any function to represent the value of a position. Several useful functions should be available as part of the datafu library. First is the standard 1/logarithmic discounting factor. Another option should be the ability to supply a custom positional value for any range of positions in the case that a positional "value" is already well understood. However, the actual discounting function used should be easily pluggable in the event something custom is needed



--
This message was sent by Atlassian JIRA
(v6.2#6252)