Section 3.3 ~ Graphics in the Media

Introduction to Probability and StatisticsMs. Young ~ room 113

Objective

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In this section, you will learn how to interpret more complex graphs that are commonly found in the media

The graphs that we will look at are: Multiple bar graph Multiple line chart Stack plot Color coded map Contour map Three-dimensional graphs

Multiple Bar Graphs A multiple bar graph is an extension of a regular bar

graph that compares two or more data sets The data sets must have the same categories

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Multiple Line Chart A multiple line chart is similar to a multiple bar graph,

but shows the data sets using lines rather than bars

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Example 1 Consider the stock, bond, and gold multiple line chart below. Suppose that, on July 7, you had invested $100 in a stock fund that tracks the S&P 500, $100 in a bond fund that follows

the Lehman Index, and $100 in gold. If you sold all three funds on September 15, how much would you have gained or lost?

The stock fund was worth about $105 on Sept. 15 th, the bond fund about $99, and gold about $100 You would have gained about $4 on your total investment since the three together are worth $304 (105 + 99 + 100) , but your initial investment was $300

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Example 2 The figure below is a multiple bar graph of the numbers of U.S.

households with computers and the number of on-line households. Redraw this graph as a multiple line chart.

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Stack Plot A stack plot shows different data sets in a vertical stack

Can be stacked using bar charts or line charts More common to stack using line charts

The thickness of a wedge at any given time tells you the value at that time

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The immigration rate to the U.S. from the Americas was about 4.6 million (5.9 – 1.3)

Example 3 The stack plot below shows death rates (deaths per 100,000

people) for four diseases since 1900. Based on this graph, what was the death rate for cardiovascular disease in 1980? Discuss the general trends visible on this graph.

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Color-Coded Map Geographical data is data that corresponds to different

geographical locations A color-coded map can be used to display geographical data

Created by color coding each category and using a basic map Allows you to see geographical trends

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Contour Map A contour map is used when data varies across

geographical areas Ex. ~ Temperatures across the U.S. over a particular

time The contours connect areas that have the same temperatures

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Three-Dimensional Graphs In some cases a graph is represented in 3-D to simply make it

look nicer Which means it is only representing two-dimensional data and a

simple bar graph would represent the data the same way Other 3-D graphs are three-dimensional for a purpose

Each of the three axes carry distinct information

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Combination Graphs Are complex graphs that contain a number of different

types of graphs

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