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AI Explorers 3-5 / Week 07 / Thursday
4/6
Week 07 · Test the Model

Thursday

Improve and test again
// Keep some cards back
⏱ about 15 min

Thursday: Improve and Test Again

Rocket groans at the tally sheet. "Three plant photos called rocks! Let's start over."

Raven spreads out the three wrong cards. "Wait. What do you notice about these plants?"

"They are all dark and brown," Rocket says slowly. "Like dry leaves."

Nova floats closer. "What could you give the model," she asks, "so it learns those plants too?"

Fix, then test again

Building a model is a loop. Build it, test it, fix it, then test again.

The crew looked at the errors. Brown plants were called rocks.

So they added more labeled cards of brown, dry plants to the training set.

They also changed a rule: look for leaves before looking at color.

Then they tested again on test cards.

THE MODEL LOOP
  • Tap a card.
  • Then tap its spot.
1First
2Next
3Then
4Last
TestRightWrongCards tested
Test 17310
Test 29110
READ THE TWO TESTS
  • Read the question.
  • Tap your answer.
How many more cards were right in Test 2 than in Test 1?
Did the fix help?
Test 2 still has 1 error. What should the crew do?
Test 1 had 3 errors. Test 2 had 1 error. How many fewer errors? Type a number.
WHY THIS EXERCISE3 minus 1 is 2, so the fix removed 2 errors.

A model can still be wrong

Even a model that scores well can make mistakes.

Real AI is a tool people build. It can be wrong too.

That is why people keep testing and checking it.

A score like 9 out of 10 means it was wrong once in that test.

StatementTrue or false?
Testing again after a fix shows if the fix worked.?
A score of 9 out of 10 means the model is never wrong.?
Studying errors can show what training cards to add.?
Real AI is built by people and can be wrong.?
WHY THIS EXERCISEFixing and testing again helps, but a model can still make mistakes.
ROCKET'S FIX, IN ORDER
  • ?Add brown plant cards to the training set.
  • ?Look at the three wrong cards.
  • ?Notice they are all brown plants.
  • ?Change the rule to check for leaves first.
  • ?Test the model again.
WHY THIS EXERCISEErrors lead to a fix, and a new test shows if the fix worked.
For a grown-up
Ask your child: what is one thing you got better at by practicing and checking?
Point out that mistakes showed them what to practice, just like the model.
Try it
Use your lab cards from Wednesday.
Change one rule to fix an error. Test your four hidden cards again.
TEST 3
  • Read the question.
  • Tap your answer.
The crew fixes the last error. Test 3 scores 10 right out of 10. How many errors?
Should the crew keep testing with new photos later?

Superb fixing! Tomorrow we look for testing in everyday life.

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