made at KIT | part of the twon project


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Job Paper

Welcome to Your New Role!

You're the lead designer of a brand-new online social network—welcome to twonderland.

In this simulation, you’ll explore how even a single design choice can ripple out to shape user behavior, spark fragmentation and fuel polarisation.

Ready to see how your decisions shape the digital world? Let’s dive in!


Welcome to the Network!

These aren’t just smiley faces—they’re users of twonderland, each one part of a larger social web.

Look closely: some are tightly connected, others link distant parts of the network.



Meet Alice’s Friends!

Alice has friends here in twonderland: Bob, Charlie, Dave, and Eve. You can see them smiling over on the right!

In twonderland, friendships are mutual—so it’s not just Alice who calls them friends. Bob, Charlie, Dave, and Eve all consider Alice a friend too.


In twonderland, users don’t just share messages—they influence each other’s moods.

Here, you can explore how Alice and Bob affect one another. Each has a sentiment slider, and the white zone around Alice shows the range of sentiments she’s open to. If Bob’s sentiment falls within that range, his message can shift Alice’s mood closer to his.

Try adjusting their sentiments, then press the button to see how Alice reacts to Bob’s message. Will she move closer to his mood?


You’re in Control: Designing the Feed

As the platform designer in twonderland, you decide how users see the world.

Each user receives messages from all their friends—but only the top one makes it through. That’s where your ranking algorithm comes in. Should messages be shown at random? Prioritize similar sentiments? Highlight the most aggressive or the calmest voices?

Click the button to assign random sentiments to Alice’s six friends. Then, choose two ranking algorithms and compare how they sort the messages.

Assume Alice has a sentiment of zero. The connecting lines show how the same friends shift positions depending on your design.

Your choices shape what Alice sees—and how she feels. What kind of world will you build?


Now, let’s see the world through Alice’s eyes.
How does your algorithm choice mess with her mood?

Remember that Alice only pays attention to messages that feel familiar — ones that land inside her white bubble of influence. And she only reads the top-ranked post the algorithm serves her.

Explore how Alice’s model is affected by your algorithm choice. Start with similarity and move Alice’s mood around. Next, see how picking a different algorithm changes her mood shifts.


It’s Not Just Alice Anymore…
Everyone’s Influencing Everyone.

The simulation breaks this down into steps. Here, you see what happens in a step.

It’s like a never-ending carousel of influence:
Each user reacts, shifts (or not), and then passes the vibe along to others.

But take your time, explore, play. Get familiar with what happens in a single timestep in twonderland.


Welcome to warp mode. 🚀

Everything moves faster. You’ll begin to see how sentiments shift and spread over time. The network has also grown—more users, more connections, more complexity.

Choose a ranking algorithm and start the simulation a few times and watch what happens. You won’t catch every detail, but you’ll start to see patterns emerge.

What algorithm is the most polarizing?
Sort the list below from most to least polarizing:

  1. 🎲 Similarity
  2. 👯 Random
  3. 🔥 Aggressiveness & 🧘 Calmness

You can edit you guess later befor checking it against the solution.

Why is are the Aggressiveness and Calmness algorithms grouped?

Both algorithms surface the most extreme sentiment. Because the aggressiveness and calmness are just different sides of the spectrum they are doing the exact same thing, just mirrored.


One Run? Fun.
Many Runs? Science!

Every time you run the simulation, things might turn out a little differently. Why? Because there’s always a bit of randomness sprinkled into the system.

So don’t trust just one run. Only by repeating the simulation can you spot the real patterns hiding in the noise.

Here, you can run 12 simulations in parallel. Do you see patterns?


This is where twonderland becomes your lab.

Now you know everything to run a scientific experiment and compare two different ranking algorithms starting from the same initial network.

Here’s your challenge:

What algorithm is the most polarizing?
Sort the list below from most to least polarizing:

  1. 🎲 Similarity
  2. 👯 Random
  3. 🔥 Aggressiveness & 🧘 Calmness

🎉 Congratulations! That was correct! 🎉
Here are explanantions of whats happening:

🎲 Random Ranking: The Peacekeeper

The feed is now in shuffle mode: posts appear in no particular order. People scroll through a colorful mix—like tossing confetti, every piece just lands wherever it happens to fall. Some posts are fiery and bold, others peaceful and mellow, and plenty sit somewhere in between. Because everything is shuffled, there’s no strong pull toward becoming more aggressive or calmer, keeping the overall mood balanced.


👯 Similarity: The Matchmaker

The feed now plays matchmaker. Posts appear based on how close their mood is to the reader’s mood. If someone feels calm, they’ll mostly see mellow posts; if they’re fired up, expect bold and fiery content. It’s like arranging confetti by color – pieces cluster together instead of scattering everywhere. Over time, these clusters turn into cozy little bubbles that rarely talk to each other. While vibes inside grow stronger, the overall conversation freezes. Everyone’s stuck in their own echo chamber, and nothing new gets through.


🔥 Aggressiveness & 🧘 Calmness: The Great Divider

The feed now plays favorites. Posts are sorted by how aggressive (or how calm) they are. When aggressiveness takes the lead, fiery content floods the feed. Calm users mostly ignore it, but those already fired up dive in and get even bolder. It’s like tossing confetti and then sweeping all the red pieces into one big pile—everyone sees the same color, but reacts differently. The gap between the fiery and the mellow grows wider. Flip the script and sort by calmness, and the same thing happens in reverse. In both cases, the algorithm drives polarization by amplifying one extreme.


⚠️ Worst Combo: Calm First, Aggressive Later

Start with fire, then flip to ice or the other way around? That’s a recipe for strong polarization. When the feed first ranks by aggressiveness, bold and fiery posts dominate, and users with an aggressive mood engage heavily—amplifying their stance. Calm users mostly withdraw. Then, switching to calmness reverses the dynamic: mellow posts take over, reinforcing serenity while side-lining bold voices. The result? Two extremes grow stronger, interaction between them fades, and the overall conversation freezes.


twonderland may look simple — and that’s the point.

Yet even in this minimal setup, the dynamics are anything but simple.

Now imagine adding more traits, more complex networks, smarter algorithms...
💥 The dynamics could explode in complexity.
That’s why we need formal tools to truly understand these systems.

You’ve seen how even the tiniest design choices can ripple through a digital society. They shape what people see, how they feel, and how they influence each other.
But here’s the twist:
The consequences of these choices are often hidden, complex, and hard to predict. That’s why we need tools like twonderland. Not just to play — but to experiment, observe, and understand. The twon project is an attempt to do exactly this.