Stem-and-Leaf Plots, Histograms, and Circle Graphs Objective: To graph and analyze data in many different ways.

Stem-and-Leaf A stem-and-leaf plot is a quick way to arrange a set of data and view its shape, or general distribution. In a stem-and-leaf plot, each data value is split into two parts; a stem and a leaf. The stems and leaves are chosen so that the data is represented in the most informative way.

Stem-and-Leaf An example of a stem-and-leaf plot is shown. A key, shown in the upper right hand corner, explains what the stems and leaves represent.

Stem-and-Leaf Suppose you want to make a stem-and-leaf plot for values ranging from 105 to 162. What stems would you use? Why? What stems would you use if the values range from 12.4 to 19.3? Why?

Stem-and-Leaf Suppose you want to make a stem-and-leaf plot for values ranging from 105 to 162. What stems would you use? Why? What stems would you use if the values range from 12.4 to 19.3? Why? stem leaf [10|5=105]

Stem-and-Leaf Suppose you want to make a stem-and-leaf plot for values ranging from 105 to 162. What stems would you use? Why? What stems would you use if the values range from 12.4 to 19.3? Why? stem leaf [12|4=12.4]

Example 1

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Histograms A histogram is a bar graph that gives the frequency of each value. In a histogram, the horizontal axis is like a number line divided into equal widths. Each width represents a data value or range of data values. The height of each bar indicates the frequency of that data value or range of data values.

Example 2

Relative Frequency Tables Relative frequency tables are frequency tables that include a column that displays how frequently a value appears relative to the entire data set. The relative frequency column is the percent frequency, or probability.

Relative Frequency Tables A relative frequency table and histogram are shown below for the canoe rental data.

Example 3

You Try Estimate the probability that a randomly selected customer will rent a canoe for less than 4 hours?

You Try Estimate the probability that a randomly selected customer will rent a canoe for less than 4 hours? = 66.6%.

Circle Graphs You can use a circle graph to display the distribution of non-overlapping parts of a whole.

Example 4

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