Lecture Notes: Data Types, Levels of Measurement, and Percent Conversions

Vocabulary flashcards covering data types, levels of measurement (nominal/ordinal, discrete/continuous), and percent/fraction/decimal concepts from Sections 2.1 and 2.3.

Qualitative data (Categorical data)

Data described by qualities or categories rather than numbers (e.g., names, descriptions, ratings).

Quantitative data

Data that are counts or measurements; numeric values.

Nominal data

Qualitative data that cannot be ordered or ranked; categories with no inherent order (e.g., area codes, ZIP codes, model/serial numbers).

Ordinal data

Qualitative data that can be ordered or ranked (e.g., ratings, sizes S/M/L/XL, hurricane categories, letter grades A–F).

Discrete data

Quantitative data that can take only specific values within a range; often counts (e.g., number of tests, credit hours, clothing sizes 2, 4, 6, 8).

Continuous data

Quantitative data that can take any value within a range; measured values with decimals (e.g., height, weight, time).

Hurricane category

An ordinal qualitative example indicating intensity on a scale (Category 1, 2, 3, …).

Model numbers

Nominal qualitative data used as identifiers for devices; no inherent order.

Area codes and ZIP codes

Nominal qualitative data used to identify geographic areas; no intrinsic order.

Letter grades (A, B, C, …)

Ordinal qualitative data that expresses quality or performance with a natural order.

Sizes (S, M, L, XL)

Ordinal qualitative data representing ordered clothing sizes.

Clothing sizes (2, 4, 6, 8, …)

Discrete quantitative data; specific size values used for garments.

Credit hours

Discrete quantitative data representing course load in hours.

Number of tests

Discrete quantitative data counting tests taken.

Miles per gallon (MPG)

Continuous quantitative measure of a car’s fuel efficiency.

Height

Continuous quantitative measurement of a person’s or object’s height.

Weight

Continuous quantitative measurement of mass.

Time (duration)

Continuous quantitative measurement of how long something lasts.

Fraction

A part/whole representation; numerator over denominator.

Percent

A fraction expressed per 100; equals (part/whole) × 100.

Decimal

A base-10 numeric representation that includes a decimal point for fractions.

Proportion

A decimal between 0 and 1 representing part of a whole (e.g., 15/20 = 0.75).

Absolute difference

The nonnegative difference between two values (the absolute value of their difference).

Relative difference

The percent change between two values: ((value − reference)/reference) × 100%.

Percent to fraction

Convert a percent to a fraction by removing % and dividing by 100.

Fraction to percent

Convert a fraction to a percent by multiplying by 100 and adding %.

Percent to decimal

Convert a percent to a decimal by dividing by 100 (move decimal two places left).

Decimal to percent

Convert a decimal to a percent by multiplying by 100 and adding % (move decimal two places right).

Qualitative vs Quantitative data

Qualitative data describe qualities or categories; Quantitative data are counts or measurements.

Nominal vs Ordinal (levels of measurement)

Nominal: categories with no inherent order; Ordinal: categories with order.

Discrete vs Continuous (quantitative data levels)

Discrete: separate, countable values; Continuous: any value within a range.