Definition
Can you teach a computer to tell cats from dogs in two minutes?
Training a model means showing it many labelled examples so that it can find a pattern linking the features to the labels. A model is the result of training: the learned pattern, ready to make predictions about new cases.
In simple words
In the activity, every animal has two clues: its size and how long its snout is. You choose which labelled examples the model learns from. When it meets a new animal, it looks for the three examples most like it and goes with the majority. The examples you choose are all it knows.
Why it matters
Training is where a model gets all of its knowledge. If the training examples are too few, one-sided or wrongly labelled, the model will be wrong in exactly those ways. Whoever chooses the training data shapes the AI.
How it works
- Choose the task: tell cats from dogs.
- Choose the features: size and snout length.
- Collect labelled examples of both kinds.
- Let the model learn from them.
- Test it on animals it has never seen.
Try it yourself
Train a model in the browser
Add labelled examples, then test the model on new animals. Try a few examples first, then more.
Common mistakes
- Training with examples of only one kind.
- Using too few examples and expecting perfect results.
- Thinking the model understands animals. It only compares numbers for size and snout.
Check yourself
Summary
- Training means learning a pattern from labelled examples.
- The trained model is the learned pattern, used on new cases.
- The training examples decide what the model knows and gets wrong.
Finished reading?
Sources: Google Machine Learning Crash Course