Showing posts with label information retrieval. Show all posts
Showing posts with label information retrieval. Show all posts

MIT-Harvard CINCS / Hamilton Institute Seminar: Inclusive Search and Recommendations from Pinterest by Dr Nadia Fawaz

From https://medium.com/pinterest-engineering/powering-inclusive-search-recommendations-with-our-new-visual-skin-tone-model-1d3ba6eeffc7


The topic of this week's MIT-Harvard CINCS  / Hamilton Institute Seminar was about "Inclusive Search and Recommendations" from Dr Nadia Fawaz, Pinterest.


Nadia Fawaz is a research scientiest and tech lead at Pinterest, and she gave an interesting talk on inclusive search and recommendations with interesting examples of this line of efforts at Pinterest when they are building their ML-based search and recommendation systems.


Why this problem is important? It has been clear that in addition to the benefits of ML systems for a wide range of domains, there are also some critical problems have been noticed such as our learned language models could be biased (e.g., "Man is to Doctor as Woman is to Nurse"). This is mainly due to the training data we collected and used to train a ML system is biased. Without considering those biases, ML loop will enhance the bias instead of eliminating it. Nadia Fawaz mentioned during her talk that bias mainly comes from demographic features such as age, skintone, gender, etc., and the talk is focused on Pinterest's efforts to build inclusive search and recommendations with skintone as an example.


Example of Pinterest inclusive AI solution for skintone [medium article]. Motivated by a top request from Pinners where they want to feel represented in the product, they built the first version of skin tone ranges, an inclusive search feature, in 2018. This aims to provide more inclusive inspirations to be recommended in search as well as allow Pinners to choose ranges for recommendations/search results. Some important aspects in terms of building inclusive service are such as:

  • data balanced across a wide range of groups (e.g., a wide range of skin tones)
  • error analysis should be tailed down to each group (so that the system does not perform well on only some specific groups while performing poor on other groups)
  • improve fairness and reduce potential bias in other ML models (e.g., incorporating fairness into objective functions)
  • also as one might expect, to achieve the goal of inclusive ML services, multidisciplinary efforts and a lot of labeling works required from domain experts.

Interestingly, at the time of writing this post, there is a comprehensive survey on "Fairness on Ranking" available on Arxiv which is highly relevant to the same topic discussed in this post.


CIKM2016 Travel Report

I attended CIKM2016, Indianapolis, USA from 23-28th October. This is the first time I attended a IR conference. It has several hundreds of attendees and it was surprising to see so many Chinese attendees from China and USA.



The conference has almost 1000 submissions (so huge number of submissions...), and both full and short tracks have around 23% acceptance rate.


The word cloud reflects hot keywords in the accepted papers, which includes deep learning and search etc.

Keynotes:

There were three keynote speakers from big companies such as MS, Google.

1. Toward Data-Driven Education
Rakesh Agrawal (Data Insights Laboratories)

2. Personalized Search: Potential and Pitfalls
Susan Dumais (Microsoft Research)

3. A Personal Perspective and Retrospective on Web Search Technology
Andrei Broder (Google Research)


The second keynote was interesting for me as the keynote speaker talked about personalization in the context of search, and mentioned the User Modeling(UM) aspect. 

Susan talked two types of UM (or user profiles), one is local profile which can be stored in PC, and the other one is cloud profile. The local profile is good considering user privacy as the profile is in the local PC for personalization, i.e., the ranking results will be personalized based on the local profile of a user. However, it suffers from in efficiency, e.g., due to the lack of portability, it will be hard to reuse it if the user changes the working environment  (e.g., change PC). Personal score was carried out by content matching as well as features based on interaction history. 

She also talked about evaluation of personalization alternatives, offline and online ones. As we can expect, the former one is safe to exploit many different alternatives. On the other hand, the later one (e.g., A/B testing) has more accurate evaluation, and with some challenges. Explicit feedback from users (e.g., asking users about the personalization is good or not) can be a good indicator, however, it also might change the user search behavior. On the other hand, implicit feedback could be noisy.

Another interesting point is personalization can also provide interesting items (serendipity)...

Tutorials

There were eight tutorials and I chose the tutorial: "Data-Driven Behavioral Analytics: Observations, Representations and Models", which was given by Dr. Meng Jiang and Dr. Jiawei Han

The tutorial is about human behavior analytics, which is one of the six disruptive research areas defined by Department of Defense. They introduced many models incorporating different factors of social network information into traditional #RecSys approaches such as Matrix Factorization (MF). 

Sessions

I also attended #RecSys session. As this conference is about IR, there were many models introduced by different problems, and MF seems like the dominated one. Surprisingly, none of the first authors came to present those papers. 

Maybe due to the venue?, there were many people didn't come either for presenting or taking CIKM cup awards...:). It was a good experience to attend the first IR conference for me, and the next CIKM(2017) will be at Singapore.