- Selecting a position that ensures that you will not be conspicuous, stand or park near a local convenience store and observe 35 consecutive individuals entering the store. Jot down whether each is
- Use the Two Proportions applet to carry out a test of significance.Let’s use our 3S strategy to help us investigate how much evidence the sample data provide to support our conjecture that Vitamin
- What are the observational/experimental units?
- The previous question gave the results of the Gallup poll where 48% of a sample of 1,014 adult Americans reported drinking at least one glass of soda pop on a typical day. Use the One Proportion
- Refer to Exercise 4.117.Probability played a role in the rigging of the April 24, 1980, Pennsylvania state lottery. To determine each digit of the three-digit winning number, each of the numbers 0,
- Probability played a role in the rigging of the April 24, 1980, Pennsylvania state lottery. To determine each digit of the three-digit winning number, each of the numbers 0, 1, 2, . . . , 9 is
- A French restaurant in Riverside, California, offers a special summer menu in which, for a fixed dinner cost, you can choose from one of two salads, one of two entrees, and one of two desserts. How
- Your family vacation involves a cross-country air flight, a rental car, and a hotel stay in Boston. If you can choose from four major air carriers, five car rental agencies, and three major hotel
- You have three groups of distinctly different items, four in the first group, seven in the second, and three in the third. If you select one item from each group, how many different triplets can you
- You have two groups of distinctly different items, 10 in the first group and 8 in the second. If you select one item from each group, how many different pairs can you form?
- The number of passengers x (in millions) and the revenue y (in billions of dollars) for the top nine U.S. airlines in a recent year are given in the following table.a. Construct a scatterplot for the
- A survey was conducted prior to the 2004 presidential election to explore the relationship between a person€™s religious fervor and their choice of a political candidate. Voters were asked
- The number of passes completed and the total number of passing yards was recorded for Brett Favre for each of the 16 regular season games in the fall of 2006.a. Draw a scatterplot to describe the
- Who are the men and women who serve in our armed forces? Are they male or female, officers or enlisted? What is their ethnic origin and their average age? An article in Time magazine provided some
- Refer to Exercise 3.19. Suppose we assume that the relationship between x and y is linear. a. Find the correlation coefficient, r. What does this value tell you about the strength and direction of
- In Exercise 2.12, Consumer Reports gave the prices for the top 10 LCD high definition TVs (HDTVs) in the 30- to 40-inch category. Does the price of an LCD TV depend on the size of the screen? The
- The makers of the Lexus automobile have steadily increased their sales since their U.S. launch in 1989. However, the rate of increase changed in 1996 when Lexus introduced a line of trucks. The sales
- Use the information from Exercise 3.9 and find the regression line. From Part A From Part A Calculate: Slope y-intercept Σχ X =. b = r Sy Sx %3D Sx = а 3D у — bх %3 Ey = Sy = Regression Line:
- Below you will find a simple set of bivariate data. Fill in the blanks to find the correlation coefficient. Covariance Calculate: ху (Σχ/(ΣΥ Σχy- Sxy n – 1 3 2 Sx: Correlation Coefficient 4
- Charitable organizations count on support from both private donations and other sources. Here are the sources of income in a recent year for several well-known charitable organizations in the United
- The price of living in the United States has increased dramatically in the past decade, as demonstrated by the consumer price indexes (CPIs) for housing and transportation. These CPIs are listed in
- Refer to Data Set #3 in the How Extreme Values Affect the Mean and Median applet. This applet loads with a dotplot for the following n = 5 observations: 27, 28, 32, 34, 37.a. What are the mean and
- Refer to Data Set #2 in the How Extreme Values Affect the Mean and Median applet. This applet loads with a dotplot for the following n = 5 observations: 2, 5, 10, 11, 12.a. Use your mouse to move the
- Refer to Data Set #1 in the How Extreme Values Affect the Mean and Median applet. This applet loads with a dotplot for the following n = 5 observations: 2, 5, 6, 9, 11.a. What are the mean and median
- Here are a few facts reported as Snapshots in USA Today.The median hourly pay for salespeople in the building supply industry is $10.41.Sixty-nine percent of U.S. workers ages 16 and older work at
- In the seasons that followed his 2001 record-breaking season, Barry Bonds hit 46, 45, 45, 5, and 26 homers, respectively (www.espn.com). Two boxplots, one of Bond€™s homers through 2001,
- How much sleep do you get on a typical school night? A group of 10 college students were asked to report the number of hours that they slept on the previous night with the following results:7, 6,
- In contrast to aptitude tests, which are predictive measures of what one can accomplish with training, achievement tests tell what an individual can do at the time of the test. Mathematics
- In a study of starting salaries of assistant professors, five male assistant professors and five female assistant professors at each of three types of institutions granting doctoral degrees were
- How satisfied are you with your current mobile-phone service provider? Surveys done by Consumer Reports indicate that there is a high level of dissatisfaction among consumers, resulting in high
- Refer to Exercise 11.72. The diagnostic plots for this experiment are shown below. Does it appear that any of the analysis of variance assumptions have been violated? Explain. Normal Probability Plot
- Each year, the American Association of University Professors reports on salaries of academic professors at universities and colleges in the United States. The following data (in thousands of
- Give the equation and graph for a line with y-intercept equal to 3 and slope equal to -1.
- Give the equation and graph for a line with y-intercept equal to - 3 and slope equal to 1.
- An experiment was designed to compare several different types of air pollution monitors. The monitor was set up, and then exposed to different concentrations of ozone, ranging between 15 and 230
- How is the cost of a plane flight related to the length of the trip? The table shows the average round-trip coach airfare paid by customers of American Airlines on each of 18 heavily traveled U.S.
- What diagnostic plot can you use to determine whether the assumption of equal variance has been violated? What should the plot look like when the variances are equal for all values of x?
- Refer to the data in Exercise 12.7. The normal probability plot and the residuals versus fitted values plots generated by MINITAB are shown here. Does it appear that any regression assumptions have
- In Exercise 3.19, Consumer Reports gave the prices for the top 10 LCD high definition TVs (HDTVs) in the 30- to 40-inch category: Does the price of an LCD TV depend on the size of the screen? The
- The number of passes completed and the total number of passing yards for Tom Brady, quarterback for the New England Patriots, were recorded for the 16 regular games in the 2006 football season. Week
- Refer to Exercise 12.11 and data set EX1211 regarding the relationship between the Academic Performance Index (API), a measure of school achievement based on the results of the Stanford 9 Achievement
- How many weeks can a movie run and still make a reasonable profit? The data that follow show the number of weeks in release (x) and the gross to date (y) for the top 10 movies during a recent week.a.
- In addition to increasingly large bounds on error, why should an experimenter refrain from predicting y for values of x outside the experimental region?
- If the experimenter stays within the experimental region, when will the error in predicting a particular value of y be maximum?
- The makers of the Lexus automobile have steadily increased their sales since their U.S. launch in 1989. However, the rate of increase changed in 1996 when Lexus introduced a line of trucks. The sales
- Is your overall satisfaction with your new pair of walking shoes correlated with the cost of the shoes? Satisfaction scores and prices were recorded for nine different styles and brands of
- You have a hot grill and an empty hamburger bun, but you have sworn off greasy hamburgers. Would a meatless hamburger do? The data in the table record a flavor and texture score (between 0 and 100)
- An experiment was designed to compare several different types of air pollution monitors. Each monitor was set up and then exposed to different concentrations of ozone, ranging between 15 and 230
- The video-sharing site YouTube attracted 19.6 million visitors in June 2006, an almost 300% increase from January of that same year. Despite YouTube€™s phenomenal growth, some analysts have
- The Academic Performance Index (API), described in Exercise 12.11, is a measure of school achievement based on the results of the Stanford 9 Achievement Test. The API scores for eight elementary
- Does the cost of a plane flight depend on the airline as well as the distance traveled? In Exercise 12.21, you explored the first part of this problem. The data shown in this table compare the
- In an investigation to determine the relationship between the degree of metal corrosion and the length of time the metal is exposed to the action of soil acids, the percentage of corrosion and
- 1. Perform a test of homogeneity for each question and verify the reported p-value of the test.2. Questions 3, 4, and 7 are concerned with the atmosphere of the library; questions 5 and 6 are
- The percentage of various colors are different for the €œpeanut€ variety of M&M€™S candies, as reported on the Mars, Incorporated website:A 14-ounce bag of peanut
- In 2006, a new law passed in Massachusetts would require all residents to have health insurance. Low-income residents would get state subsidies to help pay insurance premiums, but everyone would pay
- How long do you wait to have your prescriptions filled? According to USA Today, €œabout 3 in 10 Americans wait more than 20 minutes to have a prescription filled.€ Suppose a
- A snapshot in USA Today indicates that there is a gap in church attendence between 20-year-olds and older Americans.12 Suppose that we randomly select 100 Americans in each of five age groups and
- Is your holiday turkey safe? A €œnew federal survey found that 13% of turkeys are contaminated with the salmonella bacteria responsible for 1.3 million illnesses and about 500 deaths in a
- Parents who are concerned about public school environments and curricula are turning to homeschooling in order to control the content and atmosphere of the learning environments of their children.
- How would you rate yourself as a driver? According to a survey conducted by the Field Institute, most Californians think they are good drivers but have little respect for others€™ driving
- Each model year seems to introduce new colors and different hues for a wide array of vehicles, from luxury cars, to full-size or intermediate models, to compacts and sports cars, to light trucks.
- When you choose a greeting card, do you always look for a humorous card, or does it depend on the occasion? A comparison sponsored by two of the nation€™s leading manufacturers of greeting
- Use the Chi-Square Probabilities applet to find the value of x2 with the following area a to its right:a. α = .05, df = 15b. α = .01, df = 11
- Use the Chi-Square Probabilities applet to find the rejection region for a chi-square test of specified probabilities for a goodness-of-fit test involving k categories for the following cases:a. k =
- Use the Chi-Square Probabilities applet to calculate the p-value for the following chi-square tests:a. X2 = .81, df = 3b. X2 = 25.40, df = 13
- Three hundred people were surveyed, and were asked to select their preferred brand of laptop computer, given that the prices were equivalent. The results are shown in the table.Use the first
- In Exercise 14.13, the color distribution of M&M€™S milk chocolate candies was given. Use the third Goodness-of-Fit applet to verify the results of Exercise 14.13. Do the data
- A group of 306 people were interviewed to determine their opinion concerning a particular current U.S. foreign policy issue. At the same time, their political affiliation was recorded. Do the data in
- A study of the purchase decisions of three stock portfolio managers, A, B, and C, was conducted to compare the numbers of stock purchases that resulted in profits over a time period less than or
- The table lists the life (in months) of service before failure of a color television circuit board for 8 television sets manufactured by firm A and 10 sets manufactured by firm B. Use the Wilcoxon
- In a comparison of the prices of items at five supermarkets, six items were randomly selected and the price of each was recorded for each of the five supermarkets. The objective of the study was to
- A drug was developed for reducing cholesterol levels in heart patients. The cholesterol levels before and after drug treatment were obtained for a random sample of 25 heart patients with the
- Do you own an iPod Nano or a Sony Walkman Bean? These and other brands of MP3 players are becoming more and more popular among younger Americans. An iPod survey reported that 54% of 12- to
- Due to a variation in laboratory techniques, impurities in materials, and other unknown factors, the results of an experiment in a chemistry laboratory will not always yield the same numerical
- Find and interpret a 95% confidence interval for a population mean μ for these values:a. n = 36, x̅ = 13.1, s2 = 3.42b. n = 64, x̅ = 2.73, s2 = .1047
- The Mars twin rovers, Spirit and Opportunity, which roamed the surface of Mars several years ago, found evidence that there was once water on Mars, raising the possibility that there was once life on
- One of the major costs involved in planning a summer vacation is the cost of lodging. Even within a particular chain of hotels, costs can vary substantially depending on the type of room and the
- At a time in U.S. history when there appears to be genuine concern about the number of illegal aliens living in the United States, there also appears to be concern over the number of legal immigrants
- Refer to Exercise 8.7. What effect does increasing the sample size have on the margin of error?
- Refer to Exercise 8.5. What effect does an increased sample size have on the margin of error?a. n = 50, s2 = 4b. n = 500, s2 = 4c. n = 5000, s2 = 4
- Refer to Exercise 8.3. What effect does a larger population variance have on the margin of error?a. n = 30, σ2 = .2b. n = 30, σ2 = .9c. n = 30, σ2 = 1.5
- What are two characteristics of the best point estimator for a population parameter?
- Repeat the instructions in Exercise 7.85 when four dice are tossed.Two balanced dice are thrown, and the average number on the two upper faces is recorded.a. Use the values μ = 3.5 and σ = 1.71
- The total amount of vegetation held by the earth’s forests is important to both ecologists and politicians because green plants absorb carbon dioxide. An underestimate of the earth’s vegetative
- Refer to Exercise 7.23. Plot the standard error of the mean (SE) versus the sample size n and connect the points with a smooth curve. What is the effect of increasing the sample size on the standard
- Refer to Exercise 7.17. To find the probability that the sample mean is between 105 and 110, write down the event of interest _______. When xÌ… = 105 and xÌ… = 110,Find the
- A political analyst wishes to select a sample of n = 20 people from a population of 2000. Use the random number table to identify the people to be included in the sample.
- Students very often ask their professors whether they will be €œcurving the grades.€ The traditional interpretation of €œcurving grades€ required that the
- Consider a binomial random varible with n = 25 and p = .6. Fill in the blanks below to find some probabilities using the normal approximation.a. Can we use the normal approximation? Calculate np =
- One method of arriving at economic forecasts is to use a consensus approach. A forecast is obtained from each of a large number of analysts, and the average of these individual forecasts is the
- A normal random variable x has mean μ = 10 and standard deviation σ = 2. Find the probabilities of these x-values:a. x > 13.5b. x < 8.2c. 9.4 < x < 10.6
- Repeat Exercise 6.1. Use Table 3 and fill in the probabilities below. Write the Rewrite the Probability (if needed) Find the Probability The Interval Probability Greater than 5 Between -3 and 3
- Use the applet to find the following:a. P(x < 6) for n = 22, p = .65b. P(x = 8) for n = 12, p = .4c. P(x > 14) for n = 20, p = .5d. P(2 < x < 6) for n = 15, p = .3e. P(x ≥ 6) for n =
- Many employers provide workers with sick/personal days as well as vacation days. Among workers who have taken a sick day when they were not sick, 49% say that they needed a break! Suppose that a
- A manufacturer of videotapes ships them in lots of 1200 tapes per lot. Before shipment, 20 tapes are randomly selected from each lot and tested. If none is defective, the lot is shipped. If one or
- Although teen magazines Teen People, Hachette Filipacche, and Elle Girl folded in 2006, 70% of people in a phone-in poll said teens are still a viable market for print, but they do not want titles
- A USA Today Snapshot reports that among people 35 to 65 years old, nearly two thirds say they are not concerned about being forced into retirement. Suppose that we randomly select n = 15 individuals
- The table below shows the prices of 8 single handset cordless phones along with their overall score (on a scale of 0€“100) in a consumer rating survey presented by Consumer Reports.a.
- Acess the applet called Exploring Correlation.a. Move the slider in the first applet so that r ≈ .75. Now switch the sign using the button at the bottom of the applet. Describe the change in the
- Access the applet in How a Line Works.a. Use the slider to change the y-intercept of the line, but do not change the slope. Describe the changes that you see in the line.b. Use the slider to change