A Trip to the Roulette Wheel

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This is where we go repeatedly to the wheel, betting $1 every time. We'll go ten times and see how we do. We'll do this using Sampling, which is a powerful technique.

The Goal:

Wind up with your wheel collection and a sample from the wheel.

What to Do:

Select the collection that has your roulette wheel (Rename it wheel if you like by double-clicking its name)

Choose Sample Cases from the Analyze menu.

Fathom creates a new collection, Sample of wheel. You can see gold balls flying from the original to the sample collection. Fathom samples 10 cases by default.

Drag a new Case Table off the shelf and look at the ten cases in the sample. You'll find ten cases. You can see whether you made money or not.

Now we want to look at a new sample. Here's a key idea: Sampling is an advanced concept. In Fathom, these are hidden away from the beginning user. We control sampling in the Inspector. The inspector is a floating window with several different panels, which you select by clicking on tabs at the top.

Double-click the icon (not the name) of the sample collection. Its inspector appears. By default, it's in the Sample panel. If it isn't, click the Sample tab to get that panel. It should look like this:

Note that your collection knows that it is a sample, and what collection it is a sample of. To speed things up, you can click the Animation off. Then the gold balls don't fly.

Click the Sample More Cases button. If you have the case table positioned so you can see it, you'll see it fill with ten new cases in your sample.

Repeat this last step as many times as you like

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