Mod 1 - Organizing and Graphing Data

Vocabulary flashcards covering the construction, calculation, and graphical representation of frequency distributions and statistical data displays.

Frequency distribution

A table that shows classes or intervals of data entries with a count of the number of entries in each class.

Frequency ($f$)

The number of data entries contained within a specific class.

Class width

The distance between classes, calculated by determining the range of the data, dividing the range by the number of classes, and rounding up to the next convenient number.

Midpoint

The sum of the lower and upper limits of a class divided by two; also referred to as the class mark.

Relative frequency

The portion, or percentage, of the data that falls in a given class; calculated by dividing the class frequency $f$ by the sample size $n$.

Cumulative frequency

The sum of the frequencies of a given class and all previous classes, where the cumulative frequency of the final class is equal to the sample size $n$.

Class boundaries

The numbers that separate classes without forming gaps between them; for integer data, found by subtracting $0.5$ from each lower class limit and adding $0.5$ to each upper class limit.

Frequency polygon

A graph constructed by plotting points representing the midpoint and frequency of each class, connected with line segments from left to right, and extended to the horizontal axis one class width before the first midpoint and one class width after the last midpoint.

Relative frequency histogram

A graph that shares the same shape and horizontal scale as a frequency histogram, but uses a vertical scale that measures relative frequencies instead of frequencies.

Ogive

A cumulative frequency line graph that displays the cumulative frequency of each class plotted at its upper class boundary, with upper boundaries along the horizontal axis and cumulative frequencies along the vertical axis.

Stem-and-leaf plot

A display where each number is separated into a stem (such as the leftmost digits) and a leaf (the rightmost single digit), retaining the original data and offering an easy method to sort data.

Dot plot

A graph in which each data entry is plotted using a point above a horizontal axis.

Pie chart

A circular graph constructed using the relative frequency of each category to determine a corresponding central angle, calculated by multiplying $360^\circ$ by the category's relative frequency.

Pareto chart

A vertical bar graph where the height of each bar represents frequency or relative frequency, arranged in order of decreasing height with the tallest bar positioned on the left.

Paired data sets

Two data sets structured such that each entry in one data set corresponds directly to one entry in the second data set.

Scatter plot

A graph used to display paired data sets where the ordered pairs are plotted as points in a coordinate plane.