Descriptive Statistics Review

Use the following StatCrunch output for a sample of student ages to answer the following questions. How many students were included in the sample?

• 20

• 30

• 57

• 87

What type of variable is age in this study?

• Categorical

• Quantitative

• Lurking

What is the standard deviation for age rounded to the nearest tenth?

• 0.9

• 8.4

• 8.4114489

• 0.90180198

What is the interquartile range/IQR?

• 18

• 6

• 12

• None of the above

Which distribution has the smallest spread?

• A

• B

• C

• The spreads are approximately the same.

Which measure of central tendency is most affected by outliers or skewness of a distribution?

• A. Median

• B. Mode

• C. Mean

• D. None of the Above

A student survey was conducted at a major university, where data were collected from a random sample of 1,500 undergraduate students. One variable that was recorded for each student was the student's answer to the question: What is your favorite type of movie? Action/Comedy/Drama/Family/Horror/Musical/Science Fiction. These data would be best displayed using which of the following?

• Histogram

• Boxplot

• Stemplot

• Pie chart

A medical researcher is investigating the relationship between gender and systolic blood pressure. Which of the following is the best way to display the data collected?

• A scatterplot

• Side by side boxplots

• A two-way table

Which class has greater variability?

• 1st period

• 2nd period

If a distribution is skewed, what is the appropriate measure of spread for the data?

• Mean

• Median

• Standard Deviation

• IQR