Count Lab day. Comet clears the big workbench and sets the die in the middle.
"Thirty-six rolls," she says. "Let's see if the first rule matches Wren's log."
Wren lays his log beside the die: 18 arrivals in 6 hours. "What do you notice about the rule's guess?"
Comet counts on her fingers. "It expects 12. That is 6 short."
"Only if the rolls agree with the math," Wren says. "Let's roll and find out."
Nova hovers above the bench and projects a tally grid with six rows. "Would you like a hint?" she asks. "Write your prediction before the first roll. Then the dice cannot change your mind."
Comet hands you the die. "Data analyst, you roll first."
You will run the first rule for all 36 slots, then compare your total with the prediction and with Wren's log.
Simulations are most useful when real experiments are hard to run. The thing may be too big, too small, too fast or too slow.
Random numbers can stand in for the variety in the real world. Your die stands in for the way people arrive at different times.
| Hour | Wren's log (made-up data from the Commons Count story) | First rule expects about | Your tally |
|---|---|---|---|
| Hour 1 | 2 | 2 | (your count) |
| Hour 2 | 3 | 2 | (your count) |
| Hour 3 | 3 | 2 | (your count) |
| Hour 4 | 4 | 2 | (your count) |
| Hour 5 | 3 | 2 | (your count) |
| Hour 6 | 3 | 2 | (your count) |
| Total | 18 | 12 | (your total) |
| After you roll | True or false? |
|---|---|
| Wren's log is higher than the first rule's prediction in five of the six hours. | ? |
| Two people running the same rule can get different totals. | ? |
| One run of 36 rolls proves the rule is right or wrong for good. | ? |
| The die stands in for the real-world variety in when people arrive. | ? |
Great lab work, data analyst. Tomorrow you will turn the gap you found into a hypothesis and fix the rule.