Summary: This module provides an outline/review of key concepts related to statistical sampling and data.

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- Deals with the collection, analysis, interpretation, and presentation of data

- Mathematical tool used to study randomness

- Population
- Parameter
- Sample
- Statistic
- Variable
- Data

- Quantitative Data (a number)
- Discrete (You count it.)
- Continuous (You measure it.)

- Qualitative Data (a category, words)

*With Replacement*: A member of the population may be chosen more than once*Without Replacement*: A member of the population may be chosen only once

- Each member of the population has an equal chance of being selected

- Random
- Simple random sample
- Stratified sample
- Cluster sample
- Systematic sample

- Not Random
- Convenience sample

Samples must be representative of the population from which they come. They must have the same characteristics. However, they may vary but still represent the same population.

- The number of times an answer occurs

- The proportion of times an answer occurs
- Can be interpreted as a fraction, decimal, or percent

- An accumulation of the previous relative frequencies