Raven lays ten test cards face down. "No peeking, model," Rocket jokes.
One by one, the crew asks the sorting model for its guess. Then they flip each card.
Raven makes tally marks. "What do you notice about our two columns?"
Nova hovers over the tallies. "Count each column," she says. "Then the numbers can tell a story."
The crew's model sorts photo cards into rock, plant or tool.
For each test card, they mark right or wrong in a table.
Then they count. This is called the accuracy of the model.
Accuracy says how many were right out of how many were tried.
| Test card | True label | Model guess | Right? |
|---|---|---|---|
| 1 | rock | rock | yes |
| 2 | plant | plant | yes |
| 3 | tool | tool | yes |
| 4 | plant | rock | no |
| 5 | rock | rock | yes |
| 6 | tool | tool | yes |
| 7 | plant | rock | no |
| 8 | rock | rock | yes |
| 9 | tool | tool | yes |
| 10 | plant | rock | no |
The errors are not random. Every error was a plant called a rock.
Raven looks closely at those three cards. Each plant photo is dark and brownish.
The model seems to think dark and brownish means rock.
Finding a pattern in the errors tells us what to fix.
| Statement | True or false? |
|---|---|
| The model got all the tool cards right. | ? |
| The model got all the rock cards right. | ? |
| Errors can show a pattern we can fix. | ? |
| 3 wrong out of 10 means 3 right. | ? |
Great counting! Tomorrow you build and test your own sorting model in the Explorer Lab.