Introduction to Statistics and Levels of Measurement

Vocabulary flashcards covering basic statistical terminology, sampling concepts, hypotheses, levels of measurement, and frequency distributions.

Descriptive statistics

Statistics used to summarize or describe a group of actual numbers, representing the characteristics of a sample.

Sample

The group of participants that are actually studied in a survey or research study.

Inferential statistics

Statistics used to draw conclusions or inferences about a population based on collected sample data.

Population

The broader group of people to which the researcher intends the study results to apply.

Null hypothesis

A statistical hypothesis that states there is no difference, such as between an experimental group and a control group in a study.

Levels of measurement

A technical term describing the classification of how variables are measured, which determines the appropriate statistical test to conduct.

Nominal variable

A nonnumeric variable whose values reflect names, diagnostic categories, or attributes such as eye color.

Rank order variable

A variable whose collected values reflect relative rankings in a dataset, such as team standings or cross-country finish order.

Equal interval variable

A variable scale where equal differences between values on the scale correspond to equal differences in the underlying property being measured.

Ratio variable

An equal interval variable that possesses a true zero point, allowing for ratio comparisons (e.g., $2$\,degrees Kelvin having twice as much heat as $1$\,degree Kelvin).

True zero point

A zero point on a measurement scale that corresponds directly to an complete absence of the characteristic being measured.

Case

An individual observation, score, or participant response in a dataset, used interchangeably with the terms score and participant.

Frequency

A simple count of the number of cases or scores in a dataset that possess a specific value.

Frequency distribution

A table or summary showing the number of scores observed across a range of possible scores.