Add a personalization
touch
Mices 2022
@a2lean1

Hallo 👋
Vincent Bosc and Aline Paponaud
Adelean:●●●●Experts in Search Technologies
Integrators of Elasticsearch and Solr
Consulting, Services and Training
providersDevelopers of a2 – your Search Engine
Technology for E-Commerce andEnterprise Search

2WHAT?
WHY?
BUT!
HOW?
...And an example
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WHAT ?
(What is search personalization)

4

“Personalized search refers to web search experiences thatare tailored specifically to an individual's interests byincorporating information about the individual beyond thespecific query provided.”
Wikipedia

5CustomizationPersonalization
6PERSONALIZATIONHISTORY

AGE
GROUP

PROFILING
GENDER

GEOIP

78910

WHY ?
(Well we kind of like it)

11Businesses like personalization●According to Adweek, marketers say personalization can raise revenues
by up to 15%●

One to one pricing personalization improves proﬁts by 7.6% (Scala 1996)●Content-targeted emails can increase the click-throughs up to 62%(Ansari and Mela 2003)

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It’s great here!
He remembers
what I prefer.

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Reduce choice for users
Without SearchWith SearchInteresting item for client

With PersonalizedSearch14

Disambiguation“CREAM”

OROR

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Spread results
Queries that receive clicks on many items across all users beneﬁt more frompersonalization
Will personalization improve these queries ?

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BUT
(There are many challenges)

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“A query a user comes with usually has so much context
that the opportunity for personalization is justvery limited.”
Pandu Nayak (Google)

18Complexity●

Quality data is needed●

How much personalization do you incorporate in your formula ?

●Testing is very diﬃcult●

Same problems than recommender systems:○

Cold start○

Remove popular products from formula○

Echo chamber, Filter bubble○

Users sharing account in home19

Privacy
27% of people ﬁnd search personalization too invasive
64% reported that they felt uncomfortable because they
didn’t knowingly provide the data the brand used

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How can heknow all thatabout me? ishe stalking me?

21

22

Storing personal data
Personalization based on short-term history or within-session behavior isshown to be less valuable than long-term or across-session personalization●

Privacy implications of storing long user histories●

Massive personal data sets can be quite costly23Solutions●Transparency●Honesty●

Use only your own data●

Give the possibility of privacy to users

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HOW
(at an organization level and technically)

25

“Any organization that designs a system(defined broadly) will produce a design
whose structure is a copy ofthe organization's communication structure.”
Melvin E. Conway – Conway’s law

26

27

Recommender
Systems

Personalized Search

SearchEngines28

29

Two main techniques●

Additional boost in your query (or ﬁlter)●Reranking top N results30Collecting the data
●Straight questions to customer●

Demographic information (age, gender, geoip)●

Track customer behavior:○

Search terms○

Add to cart○

Clicks on results○

Clicks on facets

31Collaborative Filtering32Additional boost

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ML reranking●

Create your model with user features●

Personalized Learning to Rank○

Ranknet → LambdaRank → LambdaMART (Ranklib implementation)○

LTR with user features●

Rerank top n results●

Trade Oﬀ Eﬃciency vs Relevancy○

Size of n○Lower the number of features34

How to test
● AB tests● Replay sessions● Check that users are not leaving your site

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Personalized search in Carrefour France36Frequently bought items

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PRODUCT

Initial score

Modified score45,545,543,143,144,244,242,247,238

Personalized search in Carrefour France

DATA SCIENTISTSEARCH ENGINEER

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Personalized search in Carrefour France40

Takeaways
What: adding individual data in a search request to make it more relevant
Why: we ﬁnd what we want, faster and without eﬀort
But: it’s a complex challenge and respect of privacy can’t be ignored
How: mix data scientists and search engineers, add data at indexing or
search steps, and test41

Add a personalization touchThank you
Questions / Feedback / More …
@a2leaninfo@adelean.com
http://all.site
http://www.adelean.com
http://www.linkedin.com/company/adelean
http://www.meetup.com/fr-FR/search-and-data
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