Exam 2: Turning Data Into Information

Use the following information for questions: Listed below is a stem-and-leaf plot of the times it took 13 students to drink a 12 ounce beverage. Values for stems represent seconds and values for leaves represent tenths of a second. 3| 1234 3| 5 4| 0 5| 6 6| 11379 7| 8| 2 -The lower quartile is

What is the proper notation for the mean of a sample?

The head circumference (in centimeters) of 15 college-age males was obtained, resulting in the following measurements: 55, 56, 56, 56.5, 57, 57, 57, 57.5, 58, 58, 58, 58.5, 59, 59, 63. If the last measurement (63 cm's) were incorrectly recorded as 73, which one of the following statistics would change?

Use the following information for questions: A five-number summary given in Case Study 1.1 for the fastest ever driving speeds reported by 102 women was: 30, 80, 89, 95, 130. -Fill in the blank in the following sentence: Approximately 25% of the women reported a fastest ever driving speed of at most _____ mph.

An outlier is a data value that

Use the following information for questions: Suppose that amount spent by students on textbooks this semester has approximately a bell-shaped distribution. The mean amount spent was $300 and the standard deviation is $100. -What amount spent on textbooks has a standardized score equal to 0.5?

By inspection, determine which of the following sets of numbers has the smallest standard deviation.

Use the following information for questions: The following boxplot gives the distribution of the ratings of a new brand of peanut butter for 50 randomly selected consumers (100 points possible with higher points corresponding to a more favorable rating). -The median is

Which one of the following summary statistics is not a measure of the variation (spread) in a data set?

Use the following information for questions: A USA TODAY/CNN/Gallup Poll conducted April 19, 2005, was based on telephone interviews with 616 U.S. Catholics. One question asked was "When you think about your commitment to the Catholic Church, how much is your commitment affected by who the pope is -- a great deal, a moderate amount, not much, or not at all? The percentages are provided in the table below. -Approximately how many respondents stated that their commitment is not affected much?

Use the following information for questions: Suppose that the average number of years to graduate at a university is 4 years, with a standard deviation of 0.5 years. Assume a bell-shaped distribution for years to graduate. -From the Empirical Rule, what is a range of values that 68% of the students should graduate between?

Use the following information for questions: According to a national sleep foundation survey, around 31 million Americans are sleep deprived. They also say women need more sleep than men and are being short-changed. Below are the five number summaries for the number of hours of sleep at night based on a survey of American men and women. Men: 5.5, 6, 6.5, 7.5, 9 Women: 4.5, 5, 6, 7, 8 -Write a sentence to compare men versus women in terms of the median amount of sleep at night

Outliers cause complications in all statistical analyses.

Use the following information for questions: The table below provides a statistical summary of the number of CDs owned as reported by students in a class survey done at Penn State University. -What is the interquartile range for these data?

Use the following information for questions: Suppose that amount spent by students on textbooks this semester has approximately a bell-shaped distribution. The mean amount spent was $300 and the standard deviation is $100. -What percent of students spent more than $350?

Use the following information for questions: The following boxplot gives the distribution of the ratings of a new brand of peanut butter for 50 randomly selected consumers (100 points possible with higher points corresponding to a more favorable rating). -Based on the boxplot,

Use the following information for questions: The pie chart below shows the U.S. Energy Consumption by Energy Source for the year 2009. -The source with the highest consumption was

Which one of these statistics is unaffected by outliers?

Since outliers cause complications in statistical analyses, they should be discarded before computing summaries such as the mean and the standard deviation.

Which one of the following statistics would be affected by an outlier?