Probability experiment lab
Run repeatable coin, die or card-rank experiments. Increasing the trial count usually reduces random fluctuation, but it does not force the observed percentages to equal theory.
Your inputs
Start with the example values, then replace them with your own. For tables, keep the vertical bar separators and use a dot for decimals.
This is an educational model with simplified assumptions and a pseudorandom generator. Do not use its results as a forecast or for gambling decisions.
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Result and workspace
Use the start button to open your result or activity.
How it works
Use a seeded pseudorandom generator and compare observed category frequencies with equally likely theoretical probabilities.
Worked example
These sample results use the original example inputs in the form. They do not change when you edit your inputs; your own result appears in the workspace.
- Trials: 1000
| Outcome | Observed count | Observed % | Expected % |
|---|---|---|---|
| 1 | 152 | 15.2 | 16.6667 |
| 2 | 166 | 16.6 | 16.6667 |
Read the result carefully
Results depend on the values and assumptions shown above. Change one input at a time to see its effect. A blank or unavailable result means the data does not support a calculation; it is not zero.