1. Holt CA Course 1 7-5 Misleading Graphs Warm Up Warm Up California Standards Lesson Presentation Preview

2. Holt CA Course 1 7-5 Misleading Graphs Warm Up Use the graph for questions 1-3. 1. What network had the most viewers? 2. What network had the fewest viewers? 3. What network(s) had about the same viewership? ABC FOX CBS, NBC

3. Holt CA Course 1 7-5 Misleading Graphs SDAP2.3 Analyze data displays and explain why the way in which the question was asked might have influenced the results obtained and why the way in which the results were displayed might have influenced the conclusions reached. Also covered: SDAP2.5 California Standards

4. Holt CA Course 1 7-5 Misleading Graphs Sometimes data is presented in a way that influences how the data is interpreted. A data display that distorts information in order to persuade can be misleading. An axis in a graph can be “broken” to make the graph easier to read. However, a broken axis can also be misleading. In the graph at right, the cost per minute for service with Company B looks like it is twice as much as the cost for service with Company A. In fact, the difference is only $0.10 per minute.

5. Holt CA Course 1 7-5 Misleading Graphs Which graph could be misleading? Why? Additional Example 1: Weather Application The graph at left could be misleading. It gives the impression of greater temperature change because the vertical axis does not begin at zero.

6. Holt CA Course 1 7-5 Misleading Graphs Explain how you could redraw the graph so it would not be misleading. Additional Example 2A: Analyzing Misleading Graphs Draw the entire vertical scale on the graph.

7. Holt CA Course 1 7-5 Misleading Graphs Additional Example 2B: Analyzing Misleading Graphs Explain how you could redraw the graph so it would not be misleading. Make the icons for cars, light trucks, and heavy trucks the same size.

8. Holt CA Course 1 7-5 Misleading Graphs Check It Out! Example 1 Graph B could be misleading. The vertical axis does not begin at zero, so differences in scales appear greater. Graph B Which graph could be misleading? Why? Price per meal 20 15 10 5 0 Gino’s Village Grill Pasta City City Diner Graph A 25 20 15 10 5 Gino’s Village Grill Pasta City City Diner Price per meal Average Restaurant Meal Price

9. Holt CA Course 1 7-5 Misleading Graphs Explain how you could redraw the graph so it would not be misleading. Check It Out! Example 2B Water Consumed 48 40 32 24 16 Mark FrankMilaYvonne Ounces of Water Draw the entire vertical scale on the graph. The vertical axis does not start at zero so differences in water consumed seem greater.

10. Holt CA Course 1 7-5 Misleading Graphs Lesson Quiz Explain why each graph could be misleading and why. The vertical scale does not start at 0, so it looks like sales revenues were small. The scale does not start at 0, so it looks like fewer people like each type of animal. 1. 2.

11. Holt CA Course 1 7-5 Misleading Graphs Explain how you could redraw the graph so it would not be misleading. Check It Out! Example 2A Mon Tue WedThu Fri 13 12 11 10 Taxicab Fares Fare ($) Draw the entire vertical scale on the graph. The vertical axis is broken, so differences in fare appear greater.