stats chapter 1 part 1 test

What is a population?

The entire group being studied.

What is a sample?

A subset of the population selected for study.

What is a parameter?

A numerical measurement describing a population.

What is a statistic?

A numerical measurement describing a sample.

Parameter vs. statistic?

Parameter = population. Statistic = sample.

What is discrete data?

Data that can be counted and usually takes separate whole-number values.

Example of discrete data?

Number of phone calls: 425 calls.

What is continuous data?

Data that can take any value within a range and is usually measured.

Example of continuous data?

Height: 28.3 feet.

Quick way to remember discrete vs. continuous?

Discrete = count. Continuous = measure.

What is simple random sampling?

Every individual has an equal chance of being selected.

Example of simple random sampling?

Putting everyone's names in a hat and randomly drawing names.

What is systematic sampling?

Randomly choose a starting point and then select every nth person/item.

Example of systematic sampling?

Start with the 3rd student and select every 49th student.

What is stratified sampling?

Divide the population into groups based on a characteristic and randomly sample from EACH group.

Example of stratified sampling?

Divide students by grade and randomly select some freshmen, sophomores, juniors, and seniors.

What is cluster sampling?

Divide the population into natural groups, randomly select whole groups, and study everyone in those selected groups.

Example of cluster sampling?

Randomly choose several schools and interview every teacher at those schools.

What is convenience sampling?

Selecting people who are easy or convenient to reach.

Example of convenience sampling?

A politician asks their neighbors for their opinions.

Stratified vs. cluster sampling?

Stratified = some from EVERY group. Cluster = EVERYONE from SOME groups.

Simple random vs. systematic?

Simple random = individuals randomly chosen. Systematic = every nth individual.

What is descriptive statistics?

Organizing, summarizing, or displaying data that was collected.

Example of descriptive statistics?

Making a graph showing monthly precipitation from 1998.

What is inferential statistics?

Using a sample to draw conclusions about a larger population.

Example of inferential statistics?

Surveying some students and using the results to predict what all students prefer.

Descriptive vs. inferential?

Descriptive = describe the data. Inferential = infer/predict beyond the data.

Randomly selecting 6 flights and surveying EVERY passenger on those flights is what sampling method?

Cluster sampling.

Selecting 3 trucks from EACH of 6 truck models is what sampling method?

Stratified sampling.

Checking a random pizza and then every 20th pizza is what sampling method?

Systematic sampling.

Drawing 3 student names from a hat is what sampling method?

Simple random sampling.

Asking your neighbors because they’re easy to reach is what sampling method?

Convenience sampling.

Randomly choosing 2 boxes of shirts and inspecting EVERY shirt in those boxes is what method?

Cluster sampling.