Activity 2
Signals and Noise

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Background Information

Communicating a design through words alone is no easy task. However, the use of a modular system—the building bricks—enables the students to set up some sort of coordinate system. Of course, even doing this is challenging because the students must communicate the nature of the coordinate system without seeing each other. One student could begin by saying, “I am imagining a regular pattern of squares in front of me, flat on the table. The pattern is ten squares deep and ten squares wide. The size of each square is the length of a building block. I number the squares with the numbers one through ten from left to right and the letters A through J from top to bottom. That means the top left square is A1, the next one down is B1, and the lower left square is J1. We will first build the base of the monument on these coordinate positions. Then we will add the next level up, and so on.”

Much of written language is redundant. In fact, in one reading level test, every fifth word is removed and students try to fill in the blank words. If they correctly identify about three-quarters of the words, the passage matches their reading level. With speech, there are many situations where noise or other sounds make it impossible to hear every word, yet people still manage to understand what is said (such as listening to lyrics of rock music or listening to speech at a loud party).