Chapter 1-5: Introduction to Data, Surveys, and Sampling

Vocabulary flashcards covering key concepts from the lecture on surveys, sampling, data, and statistics.

Population

The entire group of individuals or units that researchers want to study or draw conclusions about.

Sample

A subset of the population selected for study, used to estimate population characteristics.

Census

Data collected from every member of the population.

Survey

A method of collecting information from individuals by asking questions; should be concise and focused to minimize respondent burden.

Random sample

A sampling method in which every member of the population has an equal chance of being selected.

Parameter

A numerical value that describes a characteristic of a population.

Statistic

A numerical value calculated from a sample used to estimate a population parameter.

Inferential statistics

The branch of statistics that uses sample data to draw conclusions about a population.

Hypothesis test

A formal procedure used to decide whether sample data provide enough evidence to support a specific claim about a population parameter.

Two-population hypothesis test

A hypothesis test that compares a statistic (like a mean) between two populations to determine if they differ.

Depression-era sampling bias

An example showing how polling data gathered from a restricted group (e.g., those with telephones or wealth) can bias results about the broader population.

Quantitative data

Numerical data that can be measured and analyzed statistically.

Sampling bias

Systematic error that occurs when the sample is not representative of the population.

Survey design considerations

Keeping surveys quick, to the point, and avoiding making respondents do unnecessary calculations to reduce bias and improve accuracy.