Statistics Graphs

Bar Graph

A bar graph contains a bar for each category of a set of qualitative data. The bars are arranged in order of frequency, so that more important categories are emphasized.

Dot plot

A dot plot is a hybrid between a histogram and a stem and leaf plot. Each quantitative data value becomes a dot or point that is placed above the appropriate class values.

Histogram

A histogram in another kind of graph that uses bars in its display. This type of graph is used with quantitative data. Ranges of values, called classes, are listed at the bottom, and the classes with greater frequencies have taller bars.

Pie Chart or Circle Graph

A pie chart displays qualitative data in the form of a pie. Each slice of pie represents a different category.

Scatterplots

A scatterplot displays data that is paired by using a horizontal axis (the x-axis), and a vertical axis (the y-axis). The statistical tools of correlation and regression are then used to show trends on the scatterplot.

Stem and Left Plot

A stem and left plot breaks each value of a quantitative data set into two pieces, a stem, typically for the highest place value, and a leaf for the other place values. It provides a way to list all data values in a compact form.

Time-Series Graphs

A time-series graph displays data at different points in time, so it is another kind of graph to be used for certain kinds of paired data. The horizontal axis shows the time and the vertical axis is for the data values. These kinds of graphs can be used to show trends as time progresses.