Sampling Methods and Concepts

1. Simple Random Sample (SRS): Each member of the population has an equal chance of being selected.

2. Census: Data collection that includes every member of the population.

3. Convenience Sample: A sample drawn from a part of the population that is easy to reach, often leading to biased results.

4. Voluntary Response Sample: A sample consisting of volunteers, typically those with strong opinions, which can result in bias.

5. Random Sampling: The process of selecting a sample in such a way that every individual has a known, equal chance of being chosen.

6. Stratified Sampling: Dividing the population into distinct subgroups (strata) and randomly sampling from each subgroup.

7. Systematic Sampling: Selecting every kkkth member from a list of the population.

8. Cluster Sampling: Dividing the population into sections (clusters) and randomly selecting entire clusters for the sample.

9. Confounding: Occurs when two variables are intertwined in such a way that their individual effects on a response variable cannot be distinguished from each other.

Types of Variables

1. Categorical Variables: Variables that categorize or describe attributes of a population. They can be:

   • Nominal: Categories with no logical order.

     • Example of Nominal: Eye color.

   • Ordinal: Categories with a logical order.

     • Example of Ordinal: Education level (e.g., high school, bachelor's, master's).

2. Numerical Variables: Variables that represent quantities and can be measured. They can be:

   • Discrete: Countable values.

     • Example of Discrete: Number of parking spots.

   • Continuous: Values that can take on any value within a range.

     • Example of Continuous: Height or temperature.

Additional Statistical Terms

1. Variable: A characteristic or attribute that can take on different values.

2. Population: The entire group of interest in a study.

3. Parameter: A numerical value summarizing a characteristic of a population (e.g., population mean).

4. Sample: A subset of the population selected for study.

5. Statistic: A numerical value summarizing a characteristic of a sample (e.g., sample mean).

These corrections and refinements should help clarify the concepts for your quiz. Good luck!