Intro to Population, Data Types, and Levels of Measurement

Vocabulary flashcards covering population concepts, data types, and levels of measurement from the lecture.

Population

The entire group of interest in a study (e.g., all voters in a country).

Sample

A subset drawn from the population used to estimate population properties.

Population parameter

A numerical characteristic that describes a population (e.g., population mean).

Sample statistic

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

Qualitative data (categorical data)

Non-numeric data such as names, labels, attributes; categories without inherent numeric value.

Quantitative data

Numeric data from measurements or counts.

Nominal level

Data classified by names or labels with no meaningful order (e.g., dog breeds, city names).

Ordinal level

Data with a meaningful order but not necessarily equal intervals (e.g., movie ratings, top rankings).

Interval level

Quantitative data with order and equal intervals but no true zero (e.g., Fahrenheit temperature; zero is a scale point).

Ratio level

Quantitative data with order, equal intervals, and a true zero; allows meaningful ratios (e.g., weight, height, age).

Natural zero

A zero that indicates none of the quantity; distinguishes ratio from interval data (e.g., zero pounds).

Discrete data

Quantitative data that take on a finite or countable number of values (e.g., number of M&Ms in a bag).

Continuous data

Quantitative data that can take any value within an interval (e.g., amount spilled, height).

Observational study

A study where the researcher observes without manipulating variables or assigning treatments.

Experiment

A study where the researcher assigns treatments and observes effects.

Convenience sample

A sample chosen for ease of access, often biased and not representative.

Systematic sample

A sample selected using a fixed interval (e.g., every kth person).

Stratified sample

A sample drawn by dividing the population into strata and sampling from each stratum.