1. © 2019 The MITRE Corporation. All rights reserved.
Quaerite – Search Relevance Toolkit
Tim Allison
tallison@apache.org, @_tallison
April 24, 2019
Haystack Conference
Approved for Public Release;
Distribution Unlimited. Case
Number 18-3138-5

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© 2019 The MITRE Corporation. All rights reserved.
Debt of Gratitude
▪ Thank you Doug Turnbull, John Berryman and Open Source
Connections for the inspiration/examples/training with tmdb and for
sharing your ground truth set!

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© 2019 The MITRE Corporation. All rights reserved.
Yet Another Toolkit? Why!?
▪ How many parameters do we have?
▪ How many permutations of those parameters are available?

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© 2019 The MITRE Corporation. All rights reserved.
Available Parameters
▪ 14 tokenizers https://lucene.apache.org/solr/guide/7_1/tokenizers.html
▪ ~45 token filters (not including language-specific token filters – see next slide)
https://lucene.apache.org/solr/guide/7_1/filter-descriptions.html
▪ Query parsers
▪ Query operators, minimum should match, should, must, not
▪ Token/field based scoring – best_fields, most_fields, cross_fields
▪ Field boosting
▪ Phrasal boosting/shingling
▪ Synonym lists, taxonomies
▪ Similarity scoring parameters (with BM25)
▪ Elevate
▪ External signal enrichment
– manual or automatic (NLP – entity extraction, categorization, etc.)
▪ Reranking via machine learning (Learning to Rank)
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© 2019 The MITRE Corporation. All rights reserved. For internal MITRE use

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© 2019 The MITRE Corporation. All rights reserved.
Each Token Filter Can Have Many Parameters
<filter class="solr.WordDelimiterFilterFactory"
protected="protwords.txt"
generateWordParts="1"
generateNumberParts="1"
catenateWords="1"
catenateNumbers="1"
catenateAll="0"
splitOnCaseChange="0"
preserveOriginal="1"/>
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© 2019 The MITRE Corporation. All rights reserved. For internal MITRE use

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© 2019 The MITRE Corporation. All rights reserved.
Overview – Offline testing toolkit
Prerequisites:
1. Reliable, generalizable ground truth
2. Reliable, useful underlying data
3. Offline metric has to have some connection to KPIs
4. Expertise – you still have to know what you’re doing!!!

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© 2019 The MITRE Corporation. All rights reserved.
Main Tools
1. Run Experiments
2. Generate Experiments
▪ All permutations (grid search)
▪ Random experiments (random search)
3. Genetic Algorithm
▪ Cross-fold validation!!!
▪ Complementary to LTR -- main diff is algorithm and in running offline to tune general settings rather
than as reranking top n

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© 2019 The MITRE Corporation. All rights reserved.
Odds and Ends
▪ Analyzer Comparison over (mostly) the index
▪ Significant Terms (yawn…for archaic versions of Solr)…and planning to
add these as parameters in “generate experiments”

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© 2019 The MITRE Corporation. All rights reserved.
Adding Porter Stemming: create account
creat
created: 709
create: 551
creating: 269
creates: 153
creat: 1
account
account: 3244
accounts: 1924
accounting: 1548
accountants: 340
accountant: 176
accounted: 134
accountability: 74
accountable: 74
accountancy: 65
account's: 7
accountant's: 7

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© 2019 The MITRE Corporation. All rights reserved.
Status
▪ Alpha release 3/22/2019 (Solr only)
▪ Beta1 release this week (?)
– This will include support for ElasticSearch
▪ Dream
– Incorporate experiment generation/GA into Rated Ranking Evaluator (RRE)
– Apache Incubator -> Top Level Project (TLP)

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© 2019 The MITRE Corporation. All rights reserved.
Links
▪ Main site: https://github.com/mitre/quaerite
▪ Examples: https://github.com/mitre/quaerite/blob/master/quaerite-
examples/README.md
▪ Contact
– tallison@apache.org
– @_tallison