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probability-examples

BehaviourComposer: ignore everything before this.

Here are a few models for exploring probabilities inspired by Seymour Papert's What’s the big idea? Toward a pedagogy of idea power. Note that NetLogo's model library also has an excellent collection of probability models.

Noisy shapes

Seymour writes:

First we imagine a child at age five using a modern iconic form of Logo to make programs using animation and music for artistic effect. An iconic random generator is used to select colors, shapes, and actions. The probability distribution of the random variables can be modified by dragging “sliders.”

This inspired a model in which a turtle draws by repeatedly going forward and turning. If the angle turned is small the shape looks like a circle. What is interesting about this program is that a range of values can be provided and the program chooses random values within the range. Different ranges can produce very different images. And some of these drawings are aesthetically appealing. While this model is not likely to be authored by a 5-year-old it gives the sense of how adding random noise to a very simple program can result in very complex outcomes. A 3-D version of this model adds tilting and rolling to the turtle's motion.

Sampling shapes

Seymour then imagines a program for controlling a robot that can make very good use of randomness. Rather than provide a virtual simulation of a robot I chose a different example: a model for estimating the area of shapes by random sampling.

Birthday coincidences

Seymour's third example is about exploring "the probability of a coincidence of birthdays in a class of N students". He suggests a use of turtles that inspired this model of for running birthday co-occurrence experiments.

BehaviourComposer: ignore everything after this.