stat 1a

Data

Systematically recorded information, whether numbers or labels, together with its context.

Case

An individual about whom (or which) we have data.

Variable

Characteristics that are being recorded for many cases.

Categorical Variable

Data types that represent groups, names, or labels rather than numbers.

Quantitative Variable

Data types that relate to measurement, amount, or quantity of something.

Population

Entire group of individuals, objects, or events that we want to study and draw conclusions about.

Sample

A smaller, manageable subset of individuals or objects chosen from a larger population.

Ordinal Variable

A categorical variable where the values have a logical, meaningful order or ranking.

Bar Chart

A graph used to display the frequency or relative frequency of categorical data.

Pie Chart

A graph used to display the relative frequency of categorical data; the relative frequency matches the size of the piece on the graph.

Parameter

A fixed, single numerical value that describes a characteristic of an entire population.

Statistic

A fixed, single numerical value that describes a characteristic of a sample.

Statistical Study

A systematic process of collecting, analyzing, exploring, and interpreting data from a sample to answer an investigative question or test a claim about a larger population.

Data

Systematically recorded information, whether numbers or labels, together with its context.

Example 1: A list of recorded exam scores (85%, 92%, 78%) along with student IDs and test dates. Example 2: A spreadsheet tracking daily high temperatures (°F) and weather conditions (Sunny, Rainy) for a month. Example 3: Survey logs showing customer satisfaction ratings (1 to 5) and the store locations visited.

Case

An individual about whom (or which) we have data.

Example 1: A single student participating in a study on standardized test performance. Example 2: One specific U.S. state (e.g., Alabama) in a table tracking state health metrics. Example 3: A single house in a dataset recording real estate build years.

Variable

Characteristics that are being recorded for many cases.

Example 1: The running time of a movie. Example 2: A person's favorite music artist. Example 3: The diameter of a pizza.

Categorical Variable

Data types that represent groups, names, or labels rather than numbers.

Example 1: Whether or not a student skipped breakfast (Yes/No). Example 2: The race or ethnicity of an individual. Example 3: A car's transmission type (Automatic or Manual).

Quantitative Variable

Data types that relate to measurement, amount, or quantity of something.

Example 1: The number of dogs staying in an animal shelter. Example 2: The age of a mother when her first child was born. Example 3: The total dollar amount spent on monthly rent.

Population

Entire group of individuals, objects, or events that we want to study and draw conclusions about.

Example 1: All Canadian public school students. Example 2: Every Medicare beneficiary living in the United States. Example 3: All registered voters in a specific city.

Sample

A smaller, manageable subset of individuals or objects chosen from a larger population.

Example 1: A group of 112,916 Canadian public school students selected for an exam study. Example 2: A randomly selected 60% of Medicare beneficiaries in each state. Example 3: A random sample of 1,433 people surveyed about iPhone ownership.

Ordinal Variable

A categorical variable where the values have a logical, meaningful order or ranking.

Example 1: A survey scale from 1 to 5 rating how much someone enjoys music. Example 2: Level of agreement on a statement (Strongly Disagree, Disagree, Neither, Agree, Strongly Agree). Example 3: Education level attained (High School, Bachelor's, Master's, Doctorate).

Bar Chart

A graph used to display the frequency or relative frequency of categorical data.

Example 1: A graph displaying counts of iPhone owners broken down across age groups. Example 2: A chart showing the total money spent across budget categories like rent, food, and bills. Example 3: A graph comparing unemployment rates across three presidential administrations.

Pie Chart

A graph used to display the relative frequency of categorical data; the relative frequency matches the size of the piece on the graph.

Example 1: A circular graph showing the percentage of monthly income allocated to savings, rent, and food. Example 2: A chart displaying the proportion of market share held by different smartphone brands. Example 3: A graph showing the percentage distribution of student grades (A, B, C, D, F) in a course.

Parameter

A fixed, single numerical value that describes a characteristic of an entire population.

Example 1: The true average standardized test score of all public school students in Canada. Example 2: The exact overall diabetes prevalence rate across all Medicare beneficiaries nationwide. Example 3: The actual proportion of all U.S. adults who own an iPhone.

Statistic

A fixed, single numerical value that describes a characteristic of a sample.

Example 1: The 13-point average test score difference observed among music students in a study sample. Example 2: The 34.7% arthritis prevalence calculated from a 60% sample of Medicare beneficiaries in Alabama. Example 3: The percentage of 1,152 surveyed adults who agreed with animal testing.

Statistical Study

A systematic process of collecting, analyzing, exploring, and interpreting data from a sample to answer an investigative question or test a claim about a larger population.

Example 1: A study evaluating whether involvement in school music programs is associated with higher exam scores. Example 2: An investigation analyzing medical claims data to determine state-level chronic disease prevalence. Example 3: A survey examining whether age group influences the likelihood of owning the newest iPhone.