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### Number and algebra

### Geometry and measure

### Probability and statistics

### Working mathematically

### Advanced mathematics

### For younger learners

# Reaction Timer Timer

The reaction timer problem introduces this interactivity which measures the amount of time taken to react to a shape appearing on-screen:

Open animation in new window

In this interactivity it is known that once a shape disappears an internal timer begins. The time until the appearance of the next shape is determined randomly through a clear, well-defined statistical process which is unknown to us. From the moment that this next shape disappears the timer resets and starts again; the random process then again determines the time until the appearence of the next shape. Familiarise yourself with the interactivity before considering this question:

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Age 16 to 18

Challenge Level

The reaction timer problem introduces this interactivity which measures the amount of time taken to react to a shape appearing on-screen:

Open animation in new window

In this interactivity it is known that once a shape disappears an internal timer begins. The time until the appearance of the next shape is determined randomly through a clear, well-defined statistical process which is unknown to us. From the moment that this next shape disappears the timer resets and starts again; the random process then again determines the time until the appearence of the next shape. Familiarise yourself with the interactivity before considering this question:

- Upon each shape disappearing there is a delay of a random length until the appearence of the next shape. How might you design an experiment to determine the nature of the random process giving rise to the delay?

How would you massage the data in this Chi-squared test to both accept and reject the hypothesis?

What's the chance of a pair of lists of numbers having sample correlation exactly equal to zero?