Chapter 1: Data Collection

Flashcards on Statistics

Statistical Thinking

To think statistically means one can understand large amounts of data and information by applying mathematical formulas, focusing on approximations rather than exact calculations.

Lurking Variable

A missing variable that skews the data.

Population

The entire group of individuals to be studied.

Sample

A subset of the population.

Individual

A single member of a population.

Statistic

A numerical summary of a sample.

Parameter

A numerical summary of a population.

Descriptive Statistics

The process of analyzing data using numbers, tables, and graphs.

Inferential Statistics

The process of extending the conclusions from a sample to the population with some measure of reliability.

Variables

Characteristics of the individuals within the population such as height, income, ethnicity, etc.

Qualitative Variables

Variables allowing classification of individuals based on attributes or characteristics (e.g., eye color, gender).

Quantitative Variables

Numerical measures of individuals where subtraction and addition can be applied (e.g., weight, temperature).

Discrete Variable

Quantitative data representing countable information (separated, one by one).

Continuous Variable

Quantitative data representing information that can be divided indefinitely (uninterrupted change).

Nominal Level of Measurement

A variable used to name, label, or categorize without attention to rank or order (e.g., Nationality).

Ordinal Level of Measurement

A variable with properties of nominal level variables where rank and order are important (e.g., Letter Grade).

Interval Level of Measurement

A variable with properties of ordinal level variables where addition and subtraction can be performed (e.g., Time).

Ratio Level of Measurement

A variable with properties of interval level variables where ratios and percentages have meaning, and multiplication and division can be performed (e.g., Crime Rates).