Inside the ContestTorben Brodt, plista GmbH

RecSys - 2012/09/13

What is plista

● Recommendation● Advertising● Network

Torben Brodt, plista Contest, 2012/09/13

● Many big publishers in DE, AT, CH, ...● "Other articles you might be interested..."● 6 billion impressions, clicks, engages, ... pM● Lots of Data

Architecture

Torben Brodt, plista Contest, 2012/09/13

Architecture

Torben Brodt, plista Contest, 2012/09/13

Tracking Success

● each time a recommender is chosen, plista will track its success.. for context and many context combinations

Torben Brodt, plista Contest, 2012/09/13

???

Architecture

Torben Brodt, plista Contest, 2012/09/13

Architecture

● every recommend() includes context data○ data denomalization, easier for development

● API (HTTP + JSON)○ Communication and Failover is handled○ Just try and error, plista won't break, return items are

validated● Anonomyization

○ its just plista cookies○ no registered users○ you cannot overtake a profile○ Click Manipulation detection

Torben Brodt, plista Contest, 2012/09/13

What is the plista Contest

● we open the data, you provide the knowledge

● develop a recommender which implements the http api

● plista will track the success, if you are smart, be the winner for the the best recommender

● best is live, best is scalable and best will work in industry - different to some other contests

● prices? weekly €250, grand price will be announced later

Torben Brodt, plista Contest, 2012/09/13

How to start (1/3)

register atcontest.plista.com

Torben Brodt, plista Contest, 2012/09/13

How to start (2/3)

● start implementation in php, java, nodejs, ...

Torben Brodt, plista Contest, 2012/09/13

How to start (3/3)

● need old data? start replay from webinterface

● try sending debug events from webinterface● wait for team activation● plista starts sending you real data● your responses are display on real

publishers

Torben Brodt, plista Contest, 2012/09/13

● Limitations?● answer recommendations within x ms

Food for your recommender

● recommend() request and "feedbacks"● both will include context

○ currently: userid, itemid and item data (title, text, img, url)

○ More "context" will follow, promised!● run optimization on context, there are so

many possibilities, recsys gave lots of ideas● any context missing? just ask● for plista recommender we have about 50

context parameters enabled● userid zero = users without cookie

Torben Brodt, plista Contest, 2012/09/13

Your recommender = our wishlist ;)

● please academia.. no more movie recommenders ;)

● concentrate on implicit feedback● think streaming / incremental

○ better to scale○ faster results, new articles are better than old

articles?● think about cross domain

○ contest is not allowed to mix items from different domains/publishers

○ want knowledge of the full data, but candidate items of a slice

Torben Brodt, plista Contest, 2012/09/13

Evaluation

For academia *Idea for Future*● from feedback at recsys, there is demand for

duration of stay, business perspectives (cpm), turning user into new customer, ...

● good recommenders might get more traffic, so how to handle different number of impressions (in different context)

Torben Brodt, plista Contest, 2012/09/13

● CTR (Click Through Rate)○ all teams have the chance to reply to the same

number of impressions, so clicks decide!● this handles invalid responses, offtimes, etc

Discussion

http://contest.plista.com plistacontest

Torben Brodttb@plista.com torbenbrodt

Torben Brodt, plista Contest, 2012/09/13

plista is hiring!plista.com/career