StellarDefining Population and Sample
Before collecting data, clearly define:
Population Sample Sampling frame
The goal: Select a sample that is representative of the population.
Why not study the whole population?
- Too expensive or time-consuming
- Population may be too large
- Testing may be destructive (e.g., testing light bulbs to failure)
Key principle: The sample should be selected using a chance mechanism (randomization) to avoid bias and allow for valid inference.