Definitions of Statistics, Probability, and Key Terms

A set of vocabulary flashcards defining fundamental terms in statistics and probability based on the introductory lecture material.

Statistics

The science that deals with the collection, analysis, interpretation, and presentation of data.

Dot plot

A simple graph consisting of a number line and dots (or points) positioned above the number line.

Descriptive statistics

The branch of statistics focused on organizing and summarizing data through methods such as graphing or calculating numerical values like an average.

Inferential statistics

Formal methods that use probability to draw conclusions from data and determine how confident we can be that those conclusions are correct.

Probability

A mathematical tool used to study randomness that deals with the chance or likelihood of an event occurring.

Population

A collection of persons, things, or objects under study.

Sample

A portion or subset selected from a larger population to gain information about that population.

Data

The actual values of the variable obtained from sampling a population, which may be numbers or words.

Statistic

A number that represents a property of a sample, serving as an estimate of a population parameter.

Parameter

A numerical characteristic of an entire population that can be estimated by a statistic.

Representative sample

A sample that contains the characteristics of the population so that a statistic accurately estimates a parameter.

Variable

A characteristic or measurement, usually notated by capital letters such as $X$ and $Y$, that can be determined for each member of a population.

Numerical variable

A variable that takes on values with equal units, such as weight in pounds and time in hours, allowing for mathematical operations.

Categorical variable

A variable that places a person or thing into a category, such as party affiliation, where performing math calculations makes no sense.

Datum

A single value of a variable.

Mean

A value calculated by adding data values together and dividing by the total number of values, technically known as the arithmetic mean.

Proportion

A ratio or fraction representing a part of a group relative to the whole, such as $\frac{22}{40}$ or $\frac{18}{40}$.