Objective
By the end, you should map a business request to both a task type (classification, regression, clustering) and a learning type (supervised, unsupervised, self-supervised, RL).
Concept map
- Supervised learning: labeled examples (spam/not spam).
- Unsupervised learning: structure without labels (review topic clusters).
- Self-supervised learning: labels generated from data structure itself.
- Reinforcement learning: sequential decisions with reward feedback.
Task types:
- Classification predicts categories.
- Regression predicts continuous numbers.
- Clustering groups similar items without predefined labels.
Worked example (online store)
- Spam filter: supervised + classification.
- Delivery ETA: supervised + regression.
- Group customer behavior profiles: unsupervised + clustering.
- Optimize discount strategy over repeated interactions: potentially RL.
Practical decision rule
Before choosing model families, ask two questions:
- Do we have trusted labels?
- Are decisions independent or sequential over time?
These two questions eliminate most wrong paths.
Quick check guidance
If someone says "predict" but there is no label, challenge the framing immediately. You may need data collection before model selection.
Three takeaways
- Learning type depends on feedback signal.
- Task type describes output shape.
- Good framing is the highest-leverage engineering step.