# Categorical Data

• Pie Charts

• Bar Graphs

• Comparative Bar Graphs

• Relative Frequency Bar Graphs

# Numerical Data (Discrete)

• Dot Plots

• Stem (and leaf) plots

• Histogram

# Numerical Data (Cumulative Frequency Plots)

• Frequency Polygon

• Ogive Plot

# Stem Plots to Compare Two Groups of Data

• Compare the distribution pulse rate before and after administering a new drug

• After

• Skewed right

• An outlier at 146

• Centered around 95

• Spread between 86 and 146

• Range of 60

• Before

• Skew right

• No outliers

• Lower center at around 70

• Spread between 68 to 110

• Smaller range of 42

# Describe the Distribution

• Shape (only for numerical data)

# Examples

• Make a stem plot of the ages in a college classroom 18, 18, 17, 21, 26, 40, 23

• Use your calculator to make a histogram of ages in a college classroom 18, 18, 17, 21, 26, 40, 23, 27, 22, 19, 20, 21, 18, 35, 32

• STAT ➡️ EDIT ➡️ Enter & Type in the data

• STAT PLOT (2ND + Y=) Turn on & Select the type

• Zoom + 9

• TRACE

• Describe the distribution of the graph above

• skew right
• Students took a statistic quiz. The score for the quiz are below. Describe the distribution of the quiz scores

• Slightly skewed left

• No outliers

• Centered around 42

• Spread of 8 to 50

• Here are the IQ test scores of a few students. Make a stem plot of these scores.

145 139 126 122 125 130 96 110 120 143

• You are interested in how students in your class get to school in the morning. You take a survey and collect the following data:

Car 15, Bus 3, Walk 5, Bicycle 8, Skateboard 1

• Construct a bar graph of your data

• Construct a relative frequency bar graph