Project C: collect data and train a model
Be able to collect your own data, train a classifier, measure its accuracy and report its mistakes.
Prerequisites
- CSpreadsheets: formulas and sortingrequired
- CProject: train an image classifier in the browserrequired
- CWrite down what you didrequired
Intuition
Project C: the whole chain — from an idea to a measured model.
- Pick a question that can be answered by classification (which kind of waste? which hand sign? which sound?).
- Collect the data yourself: at least 3 classes × 40 examples. Enter it in a spreadsheet: file, class, who collected it, the conditions.
- Split it: 30 training / 10 test per class. The test set is not touched until the end.
- Train (Teachable Machine or similar).
- Measure on the test set. Count per class — one class can be much worse than the average.
- Report it as an experiment note plus the spreadsheet.
Interactive
A confusion table — the best way to see which mistakes the model makes:
| actual \ guessed | paper | plastic | metal |
|---|---|---|---|
| paper | 9 | 1 | 0 |
| plastic | 2 | 7 | 1 |
| metal | 0 | 1 | 9 |
Accuracy: (9+7+9)/30 = 83 %. But plastic is only 70 % — and gets confused with paper. What in the data could explain that? (Transparent plastic against a white background?) That is your improvement.
Mastery means
- Collects data of your own and documents the collection
- Trains and measures a classifier with a separate test set
- Reports failure cases and one improvement
Sign in to do the exercises and build your mastery up.
Sources
- Teachable Machine (Google, gratis) — free web service
- Swedish Wikipedia — Confusion matrix (CC BY-SA 4.0) — CC BY-SA 4.0