💻 Week 08 - Class Roadmap (90 min)

2025/26 Autumn Term

Recommendation systems and their ethical challenges

Welcome to our week 08 seminar/lab class for DS101A.

We will discuss recommendation systems (RS) – and consider the ethical challenges raised by these systems, as one example of an application of unsupervised machine learning.

Preparation

To prepare for the class, you can watch a short clip from this video, where Lawrence Lessig (speaking at the LSE rather recently) talks about the consensus built around television broadcasting, and how recent technology has transformed society into a “post-broadcast democracy”, and where the impact of recommendation systems has been to create islands of (shared) perspective across society.

He also talks about “news deserts” – where “news” sources online (sometimes from adversaries) are able to fill-in information-gaps, due to the lack of any local regional newspapers. Recommendation systems are often used to provide news online.

It should take around 15 minutes of your time.

Step 00 - Unsupervised learning: recommendation systems (RS) (15m)

👨‍🏫 Teaching moment

Your tutor will outline how recommendation systems work.

• How does unsupervised learning differ from supervised learning?
• How can unsupervised learning be used to build a recommendation system?
• What forms do recommendation systems take?
  • How do you use a recommendation system?
  • What is their purpose?
• What choices are available to the designers?

Step 01 - Big questions (25m)

Let’s consider the Netflix recommendation system algorithm!

Tip 💡: We will be mostly drawing from the Pajkovi reading here.

Quality and evaluation criteria:

• What constitutes a “good” recommendation?
  • How do we know when recommendation systems are working well?
• Who gets to decide?
• Are algorithmically “good” recommendations always moral?

Step 02 - Ethical considerations (25m)

• What ethical issues do we need to consider when building recommendation systems?
• At what level should these issues be considered?

🍵 Break (~5 min)

Step 02 - Legal considerations (20m)

• How are RSs regulated in the UK, EU and US?
• Legal challenges?
• How does abstraction lead to difficulties for regulation?