Chapter 2.3
When summarizing graphs of categorical data, report the _______ and describe the _______.
variability
Suppose a group of school age children is asked, "Which of these three ice cream flavors do you like the most: vanilla, chocolate, or strawberry?" Describe a bar graph of their responses that would have the least amount of variability. Also describe a bar graph that would have the most variability. Describe a bar graph of their responses that would have the least amount of variability. Choose the correct answer below.
A bar graph with the least variability would be one in which the children favored one particular flavor, for example chocolate.
Which of the following is not true regarding bar charts and histograms?
A bar chart is used for numerical variables while a histogram is used for categorical variables.
Suppose a group of school age children is asked, "Which of these three ice cream flavors do you like the most: vanilla, chocolate, or strawberry?" Describe a bar graph of their responses that would have the least amount of variability. Also describe a bar graph that would have the most variability.Describe a bar graph that would have the most variability. Choose the correct answer below
A bar graph with the most variability would be one in which the same
What are Pareto charts?
Bar charts that are sorted from most frequent to least frequent
What are two commonly used graphs to display the distribution of a sample of categorical data?
Bar graph and pie chart
One of the authors wanted to determine the effect of changing answers onmultiple-choice tests. She studied the tests given by another professor, who had told his students before their exams that if they had doubts about an answer they had written, they would be better off not changing their initial answer. The author went through the exams to look for erasures, which indicate that the first choice was changed. In these tests, there is only one correct answer for each question. Use the bar chart to answer the question below.
No
The accompanying table gives the percent of market controlled by the most popular Internet browsers in one year. Sketch an appropriate graph of thedistribution, and comment on its important features
Pie chart and Pareto chart Browser 1 controls the highest market share.
A categorical variable is only called bimodal under what circumstances?
Two categories are nearly tied for most frequent outcomes.
Because the human eye has a difficult time judging how much area is taken up by the wedge-shaped slice of a pie chart, which of the following is true of pie charts?
Pie charts are not commonly used by statisticians or in scientific settings.
Data on obesity rates for adults in a certain region are displayed in the bar plot for three age groups. Complete parts (a) and (b) below
a) The age group that has the highest rate of obesity is 40-59because it has the tallest bars. b)The obesity rates for women are slightly higher in the 20-39 and 60+age groups. The obesity rate for men is higher in the 40-59 age group.
A survey asked gun owners what percentage of the time they had a loaded gun easily within reach when at home. The results for male gun owners are displayed in a bar chart and a pie chart. Complete parts (a) and (b) below.
a) The difference is approximately 10. b)It is easier to use a bar chart because you can compare values using the heights of the bars, whereas it can be hard to determine which of two slices in a pie chart is larger when they are close in size and not adjacent to each other
Data on the percentage of adults living in a certain area who meet the federal aerobic fitness (AF) and muscle strengthening (MS) standards are displayed in the bar plot. Complete parts (a) and (b) below
a)Fitness rates are slightly higher in Region 2 than in the other three regions. b) In each region, aerobic fitness rates were higher thanmuscle-strengthening rates.
According to anorganization, there are five leading causes of preventable death in a region. They are shown in the graph to the right, where HBP is High BloodPressure, TU is TobaccoUse, HBG is High BloodGlucose, PA is PhysicalActivity, and OO and Overweight and Obesity. Use the graph to complete parts (a) through (e).
a. Estimate how many preventable deaths result from high blood pressure. Approximately 88 million preventable deaths in one year result from high blood pressure. (Round to one decimal place as needed.) b. Estimate how many preventable deaths result from tobacco use. Approximately 44 million preventable deaths in one year result from tobacco use. (Round to one decimal place as needed.) c. Does this graph support the theory that the greatest rate of preventable death comes from overweight and obesity, as some people have claimed? No, the graph does not support the theory that the greatest rate of preventable death comes from overweight and obesity, because overweight and obesity do not cause the greatest number of preventable deaths. d. This is a bar chart with a special name because of the decreasing order of the bars. What is that name? Pareto chart
When thinking about the variability of a categorical distribution, it is sometimes useful to think of the word _______.
diversity
When describing the distribution of a categorical variable, the category that appears most often is called the _____.
mode