Question: The scatter diagram in the next column

> What does it mean to say two variables are positively associated? Negatively associated?

> A____ is a graph that shows the relation between two quantitative variables.

> The ____variable is the variable whose value can be explained by the value of the explanatory variable

> What is the difference between univariate data and bivariate data?

> Suppose that two variables, X and Y, are negatively associated. Does this mean that above-average values of X will always be associated with below-average values of Y? Explain.

> Suppose you work a part-time job and earn $15 per hour. Draw a scatter diagram that might represent the relation between your gross pay and hours worked. Is this a deterministic relation or a probabilistic relation?

> Match each word or phrase with its definition.

> Draw a scatter diagram that might represent the relation between the number of minutes spent exercising on an elliptical and calories burned. Draw a scatter diagram that might represent the relation between number of hours each week spent on Facebook and

> Explain the difference between correlation and causation. When is it appropriate to state that the correlation implies causation?

> Write a paragraph that explains the concept of correlation. Include a discussion of the role that/play in the computation.

> Explain what is wrong with the following statement: “We have concluded that a high correlation exists between the gender of drivers and rates of automobile accidents.” Suggest a better way to write the sentence.

> What does it mean if r = 0?

> What does it mean to say that the linear correlation coefficient between two variables equals 1? What would the scatter diagram look like?

> Professors Theodore Coladarci and Irv Kornfield from the University of Maine found a correlation of 0.68 between responses to questions on the RateMyProfessors.com website and typical in-class evaluations. Use this correlation to make an argument in fa

> Go to www.pearsonhighered.com/ sullivanstats to obtain the data file 4_1_49 using the file format of your choice for the version of the text you are using. The data represent the cost, return on investment, and graduation rate for a random sample of 50 c

> Consider the following data set: (a) Draw a scatter diagram with the x-axis starting at 0 and ending at 30 and with the y-axis starting at 0 and ending at 20. (b) Compute the linear correlation coefficient. (c) Now multiply both x and y by 2. (d) Draw a

> Consider the following set of data: (a) Draw a scatter diagram of the data and compute the linear correlation coefficient. (b) Draw a scatter diagram of the data and compute the linear correlation coefficient with the additional data point (10.4, 9.3). C

> The age of a person is commonly considered to be a continuous random variable. Could it be considered a discrete random variable instead? Explain.

> On the basis of the scatter diagram below, explain what is wrong with the following statement: “Because the linear correlation coefficient between age and median income is 0.012, there is no relation between age and median income.”

> The linear correlation between violent crime rate and percentage of the population that has a cell phone is -0.918 for years since 1995. Do you believe that increasing the percentage of the population that has a cell phone will decrease the violent crime

> In a study published in the Journal of the American Medical Association, researchers found that the length of time a mother breast-feeds is negatively associated with the likelihood a child is obese. In an interview, the head investigator stated, “It’s n

> Based on data obtained from the CIA World Factbook, the linear correlation coefficient between the number of television stations in a country and the life expectancy of residents of the country is 0.599. What does this correlation imply? Do you believe t

> Lyme disease is an inflammatory disease that results in a skin rash and flulike symptoms. It is transmitted through the bite of an infected deer tick. The following data represent the number of reported cases of Lyme disease and the number of drowning de

> One basic theory of investing is diversification. The idea is that you want to have a basket of stocks that do not all “move in the same direction.” In other words, if one investment goes down, you don’t want a second investment in your portfolio that is

> The ultimate goal in any sport (besides having fun) is to win. One measure of how well a team does is winning percentage. In baseball, a lot of effort goes into figuring out the variables that help to predict a team’s winning percentage. Go to www.pearso

> Consider the four data sets shown below. (a) Compute the linear correlation coefficient for each data set. (b) Draw a scatter diagram for each data set. Conclude that linear correlation coefficients and scatter diagrams must be used together in any stati

> The website that contained the American black bear data listed in Problem 30 actually had a bear whose length is 141.0 cm and weight is 100 kg, but incorrectly listed its length as 41.0 cm. (a) Redraw the scatter diagram with the incorrect entry. (b) Rec

> An engineer wants to determine how the weight of a car affects gas mileage. The following data represent the weights of various domestic cars and their gas mileages in the city for the 2015 model year. (a) Determine which variable is the likely explanato

> Explain the process of statistics.

> The following data represent the number of licensed drivers in various age groups and the number of fatal accidents within the age group by gender. (a) On the same graph, draw a scatter diagram for both males and females. Be sure to use a different plott

> Researchers wondered whether the size of a person’s brain was related to the individual’s mental capacity. They selected a sample of right-handed introductory psychology students who had SAT scores higher than 1350. The subjects took the Wechsler Adult I

> The following data represent the total compensation for 12 randomly selected chief executive officers (CEO) and the company’s stock performance in 2017. (a) One would think that a higher stock return would lead to a higher compensation. Based on this, wh

> The data in the next column represent the maximum wind speed (in knots) and atmospheric pressure (in millibars) for a random sample of hurricanes that originated in the Atlantic Ocean. (a) Draw a scatter diagram treating atmospheric pressure as the expla

> The following data represent the speed at which a ball was hit (in miles per hour) and the distance it traveled (in feet) for a random sample of home runs in a Major League baseball game. (a) A researcher wants to determine if the speed with which the ba

> The American black bear (Ursus americanus) is one of eight bear species in the world. It is the smallest North American bear and the most common bear species on the planet. In 1969, Dr. Michael R. Pelton of the University of Tennessee initiated a long-te

> A pediatrician wants to determine the relation that may exist between a child’s height and head circumference. She randomly selects eleven 3-year-old children from her practice, measures their heights and head circumference, and obtains the data shown in

> Your Fair Isaacs Corporation (FICO) credit score is used to determine your creditworthiness. It is used to help determine whether you qualify for a mortgage or credit and is even used to determine insurance rates. FICO scores have a range of 300 to 850,

> The Gallup Organization regularly surveys adult Americans regarding their commute time to work. In addition, they administer a Well-Being Survey. According to the Gallup Organization, “The Gallup-Healthways Well-Being Index Composite Score is comprised o

> For the 41 nations that participated in TIMMS, the correlation between the percentage of students who skipped class at least once in the past month and the mean score on the exam was -0.52. Does this suggest there is a linear relation between attendance

> Explain what is meant when we say “data vary.” How does this variability affect the results of statistical analysis?

> The Trends in International Mathematics and Science (TIMMS) is a mathematics and science achievement exam given internationally. On each exam, students are asked to respond to a variety of background questions. For the 41 nations that participated in T

> Put the following correlation coefficients in order from weakest to strongest in terms of strength of linear association. -1, 0.377, 0.084, -0.436, 0.444, -0.733

> Put the following correlation coefficients in order from weakest to strongest in terms of strength of linear association. -0.903, 0.339, -0.431, 0.137, 0.869

> For each of the following statements, explain whether you think the variables will have positive correlation, negative correlation, or no correlation. Support your opinion. (a) Number of cigarettes smoked by a pregnant woman each week and birth weight of

> For each of the following statements, explain whether you think the variables will have positive correlation, negative correlation, or no correlation. Support your opinion. (a) Number of children in the household under the age of 3 and expenditures on di

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> In your own words, define the four levels of measurement of a variable. Give an example of each.

> The scatter diagram drawn in Minitab shows the relation between the percentage of the population of a state plus Washington, DC, that has at least a bachelor’s degree and the median income (in dollars) of the state for 2017. Source: U.S. Census Bureau. (

> Match the linear correlation coefficient to the scatter diagram. The scales on the x- and y-axes are the same for each diagram. (a) r = -0.969 (b) r = -0.049 (c) r = -1 (d) r = -0.992

> Match the linear correlation coefficient to the scatter diagram. The scales on the x- and y-axes are the same for each diagram. (a) r = 0.787 (b) r = -0.787 (c) r = -0.053 (d) r = 0.946

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> True or False: Correlation implies causation.

> A _____ variable is a variable that is related to both the explanatory and response variable.

> True or False: If the linear correlation coefficient is close to 0, then the two variables have no relation.

> Contrast the differences between qualitative and quantitative variables. Discuss the differences between discrete and continuous variables.

> In a boxplot, if the median is to the left of the center of the box and the right whisker is substantially longer than the left whisker, the distribution is skewed________ .

> What does the five-number summary consist of?

> Explain how to determine the shape of a distribution using the boxplot and quartiles.

> Which boxplot shown to the right likely has the data with a larger standard deviation? Why?

> Does hunger improve strategic decision making? That is, if you are hungry are you more likely to make a favorable decision when the outcome of your decision is uncertain (as in business decisions)? To test this theory, researchers randomly divided 30 nor

> The data set “Tornadoes_2017” located at www.pearsonhighered.com/sullivanstats contains a variety of variables that were measured for all tornadoes in the United States in 2017. (a) Draw side-by-side boxplots of length of the tornado by month. Which mont

> Open the data 3_5_19 at www.pearsonhighered.com/sullivanstats. This data represents the amount of time of a cab ride (in seconds), the fare collected, and the payment method for a random sample of 100 rides in the City of Chicago. Source: Chicago Data Po

> It is well- documented that active maternal smoking during pregnancy is associated with lower-birth-weight babies. Researchers wanted to determine if there is a relationship between paternal smoking habits and birth weight. The researchers administered

> In April, 2014, the city of Flint, Michigan stopped buying water that came from Lake Huron and started using water from the Flint River to save money. After the move, residents of Flint started experiencing symptoms that could be attributed to the consum

> Do store-brand chocolate chip cookies have fewer chips per cookie than Keebler’s Chips Deluxe Chocolate Chip Cookies? To find out, a student randomly selected 21 cookies of each brand and counted the number of chips in the cookies. The results are shown

> Explain the difference between a population and a sample.

> Ty Cobb is one of Major League Baseball’s greatest hitters of all time, with a career batting average of 0.366. Source: baseball-almanac.com

> A student wanted to know whether Centrum vitamins dissolve faster than the corresponding generic brand. The student used vinegar as a proxy for stomach acid and measured the time (in minutes) it took for a vitamin to completely dissolve. The results are

> In Problem 26 from Section 3.1, we drew a histogram of the length of eruption of California’s Old Faithful geyser and found that the distribution is symmetric. Draw a boxplot of these data. Use the boxplot and quartiles to confirm the distribution is s

> In Problem 25 from Section 3.1, we drew a histogram of the weights of M&Ms and found that the distribution is symmetric. Draw a boxplot of these data. Use the boxplot and quartiles to confirm the distribution is symmetric. For convenience, the data are d

> The following data represent the weight (in grams) of a random sample of 25 Tylenol tablets. (a) Construct a boxplot. (b) Use the boxplot and quartiles to describe the shape of the distribution.

> The data below represent the age of the mother at the time of her first birth for a random sample of 30 mothers. (a) Construct a boxplot of the data. (b) Use the boxplot and quartiles to describe the shape of the distribution.

> The following data represent the percentage of workers who carpool to work for the 50 states plus Washington, D.C. Note: The minimum observation of 7.2% corresponds to Maine and the maximum observation of 16.4% corresponds to Hawaii. (a) Find the five-nu

> The following data represent the age of U.S. presidents on their respective inauguration days (through Donald Trump). (a) Find the five-number summary. (b) Construct a boxplot. (c) Comment on the shape of the distribution.

> Jessica enrolled in a course that promised to increase her reading speed. To help judge the effectiveness of the course, Jessica measured the number of words per minute she could read prior to enrolling in the course. She obtained the following five-numb

> After giving a statistics exam, Professor Dang determined the following five-number summary for her class results: 60 68 77 89 98. Use this information to draw a boxplot of the exam scores.

> Use the side-by-side boxplots shown to answer the questions that follow. (a) To the nearest integer, what is the median of variable x? (b) To the nearest integer, what is the first quartile of variable y? (c) Which variable has more dispersion? Why? (d)

> Read the newspaper article and answer the following questions: (a) What is the research question the study addresses? (b) What is the sample? (c) What type of variable is season in which you were born? (d) What can be said (in general) about individuals

> Use the side-by-side boxplots shown to answer the questions that follow. (a) To the nearest integer, what is the median of variable x? (b) To the nearest integer, what is the third quartile of variable y? (c) Which variable has more dispersion? Why? (d)

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> ______ divide data sets into fourths.

> The_______ of a data set is a value such that k percent of the observations are less than or equal to the value.

> The_______ represents the number of standard deviations an observation is from the mean.

> Explain what each quartile represents.

> Explain the circumstances for which the interquartile range is the preferred measure of dispersion. What is an advantage that the standard deviation has over the interquartile range?

> Explain the advantage of using z-scores to compare observations from two different data sets.

> Mensa is an organization designed for people of high intelligence. One qualifies for Mensa if one’s intelligence is measured at or above the 98th percentile. Explain what this means.

> Suppose a fundraiser holds a raffle for which each person who enters the room receives a ticket numbered 1 to N, where N is the number of people at the fundraiser. The first person to arrive receives ticket number 1, the second person receives ticket num

> When outliers are discovered, should they always be removed from the data set before further analysis?

> Morningstar is a mutual fund rating agency. It ranks a fund’s performance by using one to five stars. A one-star mutual fund is in the bottom 10% of its investment class; a five-star mutual fund is at the 90th percentile of its investment class. Interpre

> Suppose you received the highest score on an exam. Your friend scored the second-highest score, yet you both were in the 99th percentile. How can this be?

> Write a paragraph that explains the meaning of percentiles.

> Use the fraud-detection data from Problem 25 to do the following. (a) Determine the standard deviation and interquartile range of the data. (b) Suppose the month in which the customer used 346 minutes was not actually that customer’s phone. That particul