Exam 5: Statistical Reasoning

The graph below shows estimated world population for the period $4000 B C = 2000 A D$ . Note that the logarithm of the world population and not actual population is plotted on the vertical axis. This means, for example, that when the graph reaches 7 on the vertical scale, world population is $10 ^ { 7 }$ and when the graph reaches 9 on the vertical scale, world population is $10 ^ { 9 }$ . Use the graph to answer the question. -During the period 4000 BC to 1000 BC, approximately what was the doubling time for world population?

Use the guidelines to evaluate the study. From the information given, what is the biggest flaw in the study? -A high school principal wanted to know how the teachers at her school felt about early dismissal for Homecoming. She put the names of the 114 faculty in a hat and randomly selected 30 of the Names. She gave questionnaires to those 30 people asking whether they agreed or disagreed with The following statement: "Valuable learning time should not be sacrificed for extracurricular social Activities." The questionnaires were filled out anonymously. Her conclusion was that 80% of the Faculty were opposed to early dismissal for Homecoming.

Answer the question. -The graph below shows the approximate annual percentage growth rate in world population for the years 1960 through 2010. Data is estimated by the UN Census Bureau. Why must the graph be interpreted with care? If the graph is not interpreted with care what misleading impression might one have of world population during the period 1960-2010? In which year during the period 1960-2010 is estimated world population the greatest? During which years did world population increase at the fastest rate? Summarize the overall trends in world population during the period 1960-2010.

In order to answer the given question, which of the following types of study would be the most appropriate: anexperiment without blinding, an experiment with single blinding, an experiment with double blinding, an observationalstudy, or a case-control study? -Do Super-Slimmer Shakes increase weight loss?

Use the guidelines to evaluate the study. Discuss flaws that you see in the study. -An educational researcher wishes to compare the effectiveness of two different math textbooks. She has the tenth graders at one school use the first book for one year and the tenth graders at another school use the second textbook for one year. At the end of the year, she gives the same math test to both classes and compares the results.

Answer the question. -What name is given to a statistical graph that is embellished with additional art work?

The graph below shows the approximate annual percentage growth rate in world population for the years 1960 through 2010. Data is estimated by the UN Census Bureau. Annual Growth Rate (Percentage) Use the graph to answer the question. -Describe the trend in world population during the period 1976-1978

Make a bar graph to represent the data. -Construct a vertical bar graph for the relative frequencies given. Blood type Frequency Relative frequency 22 0.44 19 0.38 6 0.12 3 0.06

Choose the best wording for the question in the study. -In a survey to assess attitudes toward genetically modified foods, which of the following survey questions will give the most accurate results?

Determine whether the study involves selection bias, participation bias, both selection bias and participation bias, orneither. -As voters left various polls across the city, every tenth voter at each polling place was asked who they had chosen to be the next mayor.

Construct a line chart for the data. - Weight of Cat (lb) Frequency 5-7 2 8-10 9 11-13 18 14-16 13 17-19 4 20-22 1

Construct a pie chart representing the given data set. - Main form of exercise for employees of one company: None: 30\% Walking: 18\% Running: 4\% Golf: 11\% Weight Training: 26\% Other: 11\%

Use the graph to answer the question. - What was the revenue for the first quarter of 2000 ?

Identify the variable as either qualitative or quantitative. -The population of a town

Make a bar graph to represent the data. -The following table shows the number of inches of rainfall measured at City X during the following days. Create a horizontal bar graph. Day No. of Inches of Rainfall April 9 1.26 April 24 1.94 May 9 3.26 May 24 2.54 June 9 2.02 June 24 1.86

Answer the question. -In a study to determine the average weight of a house cat, which of the following is the most representative sample?

The graph below shows the approximate annual percentage growth rate in world population for the years 1960 through 2010. Data is estimated by the UN Census Bureau. Use the graph to answer the question. -Describe the trend in world population during the period 1960-1962

Identify the variable as either qualitative or quantitative. -The marital status of individuals

Answer the question. -Which of the following describes a study in which the participants naturally form groups by choice?

Provide an appropriate response. -Suppose that you want to construct a graph to represent the following data. Blood Type Frequency 90 84 18 8 If you are primarily interested in the number of people in each category as a percentage of the total number of people, would a bar chart or a pie chart be more useful? Explain your thinking.