Recommendation feed: what your feed learns about you
About this app
A short-video feed as a model: watch time, likes and rewatches become a signal, the interest profile learns, candidates are ranked. With an exploration slider you can see how a feed that only exploits narrows to one topic, and how searching, resetting and exploring widen it again.
With explain mode: an AI tutor walks you through the app, points out what matters in the scene and answers your questions.
Signals, profile, ranking
A short-video feed watches how you react to each video: how long you look, whether you like it, whether you watch it again. These signals flow into an interest profile. For the next video the system first selects candidates from a large pool and then ranks them by the engagement it predicts. This two-stage design of candidate generation and ranking is described in technical publications. Providers keep secret which signals count how much; watch time, however, is recorded for every video, even without a single tap.
What the app shows
A phone with a simulated feed of six topics, with the three signals as bars below it. Next to it twelve candidates and the ranking, on the right the interest profile as a radar and, dashed, the simulated person’s real taste. The history shows the latest videos as tiles and the variety, that is, how many topics effectively appear in the last 20 videos. Weights and reactions are a simplified model, not a copy of any particular app.
Try it yourself
Set “Exploration” to 0 % and let the feed run fast: after a few videos it shows almost only one topic, and variety drops to 1. Then search for another topic yourself, reset the profile and allow 30 % exploration. Compare the three simulated people: someone who reacts strongly to nothing gets a more varied feed than someone with a clear favourite topic.
Frequently asked questions
- How does a feed know what I like?
- From your behaviour: how long you watch a video, whether you like, share, comment or rewatch it, and which videos you swipe away quickly. These signals flow into an interest profile. A feed does not need taps for this; watch time alone reveals a lot.
- What is the difference between exploiting and exploring?
- Exploiting means showing what works best according to the profile so far. Exploring means deliberately showing something else to learn something new about the person. A system that only exploits learns nothing more about the other topics and narrows.
- Can I get a feed without an algorithm?
- In the EU, very large platforms must offer at least one feed option that is not based on profiling under the Digital Services Act (Article 38). According to its key points of 14 October 2026, the German government wants recommender systems to be switched off by default.
- What can I try out in this app?
- You swipe through a simulated feed, see the signals of every video, the ranking of the candidates and how the interest profile grows. With the “Exploration” slider, a search and a profile reset you control how varied the feed stays.
Subject: Film & media
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