AP Stats: Section 1a - Learning from Data

Statistics

The science and art of collecting, analyzing, and drawing conclusions from data

Statistical problem-solving process

Formulate questions

Collect data

Analyze data

Interpret results

Data

Most statistical studies collect ___ from samples to answer investigative questions about larger populations.

vary

A valid investigative study is based on data that ___.

Population

The entire group of items or individuals we want information about in a statistical study

Census

Collects data from every item or individual in the population

Sample

A subset of items or individuals in the population from which we collect data

Statistic

A number that describes some characteristic of a sample

Parameter

A number that describes some characteristic of a population

Observational unit

An item or individual described in a data set or statistical study. Observational units may be people, animals, or things.

Variable

A characteristic that can take different values for different observational units

Categorical variable

Takes values that are labels, which place each individual into a larger group, called a category

Quantitative variable

Takes number values that are quantities—counts or measurements

Discrete quantitative variable

Can take a set of possible values with gaps between them on the number line (usually result from counting something)

Continuous quantitative variable

Can take any value in an interval on the number line (usually result from measuring something)