A hypothesis testing video game

by Swimmy 1 min read1st Apr 201312 comments


The Blob Family is a simple game made by Leon Arnott. At heart, it's a game about testing hypotheses and getting the right answer with the least amount of evidence you can.

The mechanics work like so: Balls bounce around the screen randomly and you control a character who needs to avoid them. You can aim the mouse anywhere and activate a sonar. On the right side are rules for how various balls will react to this, and your goal is to figure out which ball is which. As you use the sonar more, the balls speed up, so it becomes more difficult to stay alive, thus giving an incentive to test your hypothesis in as few clicks as possible.

It very nicely illustrates the principle that, to test a hypothesis, you must design tests to falisfy your intuitions rather than to confirm them. For example, in one level, when you use the sonar:

  • 1 ball heads toward the center
  • 1 ball heads away from the center
  • 1 ball heads away from the mouse
  • 1 ball heads away from you

I found myself mistakenly clicking in the center of the screen to test hypothesis 1, but this is insufficient. To design the proper tests, you need to keep the mouse out of the center, keep it away from you, and depending on the position of the balls keep it off a straight line from you.

It could also demonstrate the ability of a fast brain to test hypotheses quickly. For many levels, if you could slow time down and set up a very good test, you could solve the problem with a single click. But we humans aren't usually so attentive.

Just thought the LW crowd might enjoy it.