A Gallup survey asked a random sample of federal government and private sector workers to judge their well-being. The responses are 1 = thriving, 2 = struggling, 3 = suffering. Is there enough evidence to conclude that government and private sector workers differ in their well-being?
> Stress is a serious medical problem that costs businesses and government billions of dollars annually. As a result, it is important to determine the causes and possible cures. It would be helpful to know whether the causes are universal or do they vary f
> A management behavior analyst has been studying the relationship between male/female supervisory structures in the workplace and the level of employees’ job satisfaction. The results of a recent survey are shown in the accompanying tabl
> Suppose that the personnel department in Exercise 15.87 continued its investigation by categorizing absentees according to the shift on whichthey worked, as shown in the accompanying table. Is there sufficient evidence at the 10% significancelevel of a r
> It has been estimated that employee absenteeism costs North American companies more than $100 billion per year. As a first step in addressing the rising cost of absenteeism, the personnel department of a large corporation recorded the weekdays during whi
> An organization dedicated to ensuring fairness in television game shows is investigating Wheel of Fortune. In this show, three contestants are required to solve puzzles by selecting letters. Each contestant gets to select the first letter and continues s
> In Exercise 13.115, you performed a test of the mean matched pairs difference. Test with a 10% significance level to determine whether the normality requirement is violated.
> Exercise 13.26 asked you to conduct a t-test of the difference between two means (reaction times). Test to determine whether there is enough evidence to infer that the reaction times are not normally distributed. A 5% significance level is judged to be s
> Exercise 13.25 required you to conduct a t-test of the difference between two means. Each samples productivity data are required to be normally distributed. Is that required condition violated? Test with = .05.
> The t-test in Exercise 12.37 requires that the costs of prescriptions is normally distributed. Conduct a test with = .05 to determine whether the required condition is unsatisfied. If there is enough evidence to conclude that the requirement is not sat
> Refer to Exercise 12.31. Test at the 10% significance level to determine whether the amount of time spent working at part-time jobs is normally distributed. If there is evidence of nonnormality, is the t-test invalid? Data from Exercise 12.31: A growing
> To determine whether a single die is balanced, or fair, the die was rolled 600 times. Is there sufficient evidence to allow you to conclude that the die is not fair?
> A random sample of 50 observations yielded the following frequencies for the standardized intervals: Can we infer that the data are not normal? (Use  = .10.) Interval Frequency Zs-1 6 -1 <Z<0 27 0<ZS1 Z>1 14 3
> Suppose that a random sample of 100 observations was drawn from a population. After calculating the mean and standard deviation, each observation was standardized and the number of observations in each of the following intervals was counted. Can we infer
> The president of a company that manufactures automobile air conditioners is considering switching his supplier of condensers. Supplier A, the current producer of condensers for the manufacturer, prices its product 5% higher than supplier B. Because the p
> Automobile insurance companies take many factors into consideration when setting rates. These factors include age, marital status, and miles driven per year. To determine the effect of gender, 2 years of driving experience) male and female drivers was su
> The cruise ship business is rapidly increasing. Although cruises have long been associated with seniors, it now appears that younger people are choosing a cruise as their vacations. To determine whether this is true, an executive for a cruise line sample
> In random samples of 12 from each of two normal populations, we found the following statistics: x1 = 74 s1 = 18 x2 = 71 s2 = 16 a. Test with = .05 to determine whether we can infer that the population means differ. b. Repeat part (a) increasing the s
> In assessing the value of radio advertisements, sponsors consider not only the total number of listeners but also their ages. The 18 to 34 age group is considered to spend the most money. To examine the issue, the manager of an FM station commissioned a
> Is eating oat bran an effective way to reduce cholesterol? Early studies indicated that eating oat bran daily reduces cholesterol levels by 5% to 10%. Reports of this study resulted in the introduction of many new breakfast cereals with various percentag
> The president of Tastee Inc., a baby-food producer, claims that her company’s product is superior to that of her leading competitor because babies gain weight faster with her product. (This is a good thing for babies.) To test this claim, a survey was un
> How do drivers react to sudden large increases in the price of gasoline? To help answer the question, a statistician recorded the speeds of cars as they passed a large service station. He recorded the speeds (mph) in the same location after the service s
> Because there are no national or regional standards, it is difficult for university admission committees to compare graduates of different high schools. University administrators have noted that an 80% average at a high school with low standards may be e
> A growing concern among fans and owners is the amount of time to complete a major league baseball game. To assess the extent of the problem, a statistician recorded the amount of time (in minutes) to complete a random sample of games 5 years ago and this
> Who spends more on their vacations, golfers or skiers? To help answer this question, a travel agency surveyed 15 customers who regularly take their spouses on either a skiing or a golfing vacation. The amounts spent on vacations last year are shown here.
> A number of restaurants feature a device that allows credit card users to swipe their cards at the table. It allows the user to specify a percentage or a dollar amount to leave as a tip. In an experiment to see how it works, a random sample of credit car
> A men’s softball league is experimenting with a yellow baseball that is easier to see during night games. One way to judge the effectiveness is to count the number of errors. In a preliminary experiment, the yellow baseball was used in
> a. Apply Tukey’s multiple comparison method to determine which fertilizers differ in Exercise 14.14. b. Repeat Part a applying the Bonferroni adjustment.
> An engineering student who is about to graduate decided to survey various firms in Silicon Valley to see which offered the best chance for early promotion and career advancement. He surveyed 30 small firms (size level is based on gross revenues), 30 medi
> Refer to Exercise 14.12. a. Apply Fisher’s LSD method with the Bonferroni adjustment to determine which lacquers differ. b. Repeat Part a applying Tukey’s method instead. Data from Exercise 14.12: A manufacturer of outdoor brass lamps and mailboxes has
> Police cars, ambulances, and other emergency vehicles are required to carry road flares. One of the most important features of flares is their burning times. To help decide which of four brands on the market to use, a police laboratory technician measure
> a. Apply Tukey’s multiple comparison method to determine which forms differ in Exercise 14.10. b. Repeat Part a applying the Bonferroni adjustment.
> a. Apply Fisher’s LSD method with the Bonferroni adjustment to determine which schools differ in Exercise 14.9. b. Repeat Part a applying Tukey’s method instead.
> A multinomial experiment was conducted with k = 4. Each outcome is stored as an integer from 1 to 4 and the results of a survey were recorded. Test the following hypotheses. H0: p1 = .15, p2 = .40, p3 = .35, p4 = .10 H1: At least one pi is not equal to i
> Refer to Exercise 14.6. a. Employ Fisher’s LSD method to determine which degrees differ (use = .10). b. Repeat Part a using the Bonferroni adjustment. Data from Exercise 14.6: Many college and university students obtain summer jobs. A statistics profess
> Apply Tukey’s method to determine which brands differ in Exercise 14.5.
> Developing an Understanding of Statistical Concepts a. Use Fisher’s LSD procedure with _ = .05 to determine which population means differ given the following statistics: k = 5 n1 = 5 n2 = 5 n3 = 5 MSE = 125 x1 = 227 x2 = 205 x3 = 219 n4 = 5 n5
> Developing an Understanding of Statistical Concepts a. Use Fisher’s LSD method with _ = .05 to determine which population means differ in the following problem. k = 3 n1 = 10 n2 = 10 n3 = 10 MSE = 700 x1 = 128.7 x2 = 101.4 x3 = 133.7 b. Repeat Par
> Every month a clothing store conducts an inventory and calculates losses from theft. The store would like to reduce these losses and is considering two methods. The first is to hire a security guard, and the second is to install cameras. To help decide w
> An avid golfer has just purchased a new putter with a money-back guarantee. She plays seven rounds with the new putter and seven rounds with her old putter and records the number of putts. Can the golfer conclude that the new putter is better? Old pu
> In random samples of 25 from each of two normal populations, we found the following statistics: x1 = 524 s1 = 129 x2 = 469 s2 = 141 a. Estimate the difference between the two population means with 95% confidence. b. Repeat part (a) increasing the stand
> Refer to Exercise 13.52. The data for public servants’ sick days 5 years ago was alsorecorded. Is there sufficient evidence to conclude that there are more sick days this year than 5 years ago? Data from Exercise 13.52: Are Canadian public servants gami
> A critical issue for service companies is how many customers cancel. Some wireless carriers lose an average of 3% of their subscribers eachmonth. Should companies spend more effort gettingnew customers or trying to win back old customerswho left? Researc
> Repeat Exercise 15.1 with the following frequencies: Cell 1 2 3 4 5 Frequency 12 32 42 36 28 Data from Exercise 15.1: Consider a multinomial experiment involving n = 300 trials and k = 5 cells. The observed frequencies resulting from the
> Consider a multinomial experiment involving n = 300 trials and k = 5 cells. The observed frequencies resulting from the experiment are shown in the accompanying table, and the null hypothesis to be tested is as follows: H0: p1 = .1, p2 = .2, p3 = .3, p4
> As a general rule more education leads to more professional and financial success. Test to determine whether heads of households with a high school diploma (EDCL: 1 = no high school diploma, 2 = high school diploma) have more household assets than those
> If people who work for someone else have more assets and greater net worth than self-employed people (OCCAT1: 1 = someone else, 2 = self-employed/partnership) we would expect them to have larger unrealized capital gains (KGTOTAL). Conduct a test to deter
> Is there sufficient evidence to infer that self-employed heads of households (OCCAT1: 1 = someone else, 2 = self-employed/partnership) have less net worth than heads of household who work for someone else (NETWORTH)?
> Are married heads of households (MARRIED: 1 =married or living with partner, 2 = not married or living with partner) less likely to have declared bankruptcy in the last five years? Conduct a test to answer the question (BNKRUPLAST5: 1 = Yes).
> Is there enough evidence to infer that married heads of households (MARRIED: 1 =married or living with partner, 2 = not married or living with partner) are more likely to be self-employed (OCCAT1: 2 = Self-employed/ partnership)?
> The results of a multinomial experiment with k = 5 were recorded. Each outcome is identified by the numbers 1 to 5. Test to determine whether there is enough evidence to infer that the proportions of outcomes differ.
> With marriage comes financial responsibilities. If so, we would expect married heads of households (MARRIED: 1 = married or living with partner, 2 = not married or living with partner) to be less likely to be unemployed (LF: 0 = Not working). Is there su
> Are married heads of households (MARRIED: 1 =married or living with partner, 2 = not married or living with partner) more likely to have a college degree (EDCL: 4 = College degree)? Conduct a test to answer the question.
> What conclusions can you draw from the results of the four previous exercises?
> Is there enough statistical evidence to infer that male heads of households (HHSEX: 1 = male, 2 = female) are more likely to be married (or living with partner) than female heads of households (MARRIED: 1 = Married or living with partner)?
> Is there sufficient evidence to conclude that male heads of households (HHSEX: 1 = male, 2 = female) are more likely to own the home they live in (HOUSECL: 1 = Owns)?
> If male heads of households (HHSEX: 1 = male, 2 = female) are more likely to have a college degree does it follow that they have a higher employment rate (LF: 1 = Working in some way)? Conduct a test to answer the question.
> Many studies show that women are more likely to have a college degree than men. However, does this apply to female and male heads (HHSEX: 1 = male, 2 = female) of households? Is there enough evidence to conclude that male heads of households are more lik
> Refer to Exercise 13.123. Do the data allow us to conclude that there is more variation in total capital gains (KGTOTAL) for self-employed individuals than for employees? Data from Exercise 13.123: The financial rewards for self-employment can be consid
> Refer to Exercise 13.123. Is there more variation in the amount of debt of the self-employed than for employees (DEBT)? Data from Exercise 13.123: The financial rewards for self-employment can be considerable. The downside may be that one works long hou
> Refer to Exercise 13.123. Is there enough evidence to conclude that the variation in net worth is greater for the self-employed than for employees (NETWORTH)? Data from Exercise 13.123: The financial rewards for selfemployment can be considerable. The d
> In 2013, the Supreme Court of the United States ruled on a California law that banned same-sex marriage. An important element of that decision was public opinion. In March, Public Policy Polling conducted a survey of Florida voters and asked each to iden
> The financial rewards for selfemployment can be considerable. The downside may be that one works long hours accruing debts with little or no financial return. As a result we theorize that the variance in compensation will be greater for the self-employed
> Capital gains can be produced in a number of ways. Most homeowners have unrealized capital gains on the homes. Estimate with 95% confidence the mean amount of all capital gains except the home (KGHOUSE = unrealized capital gains on the primary residence;
> In terms of income, do heads of middle class households consider this to be a worse year than normal? Conduct a test to answer the question (INCOME = household; NORMINC = household normal income).
> Refer to Exercise 14.52. Apply Tukey’s method to determine whether there is enough statistical evidence to infer that each pair of means differ. Data from Exercise 14.52: Is there enough evidence to conclude that there are differences in total annual am
> Refer to Exercise 14.51. Use Tukey’s multiple comparison method to determine which pairs of means differ. Data from Exercise 14.51: Do households headed by a more educated person spend their food dollars differently from households headed by less-educat
> Is there enough evidence to infer that heads of households who finish high school (EDCL: 1 = no high school diploma, 2 = high school diploma) have greater net worth than those who did not complete high school (NETWORTH)?
> In most countries including the United States, men have higher incomes than women. Does this hold when comparing middle class heads of households (HHSEX: 1 = male, 2 = female)? a. Is there sufficient evidence that male heads of households have higher inc
> Do college graduates have smaller unrealized capital gains (KGTOTAL) in their households than do households with only some college (EDCL: 3 = some college, 4 = college degree)? Conduct a test to answer the question.
> Estimate how much greater income (INCOME) is earned in households whose heads completed college (EDCL: 3 = some college, 4 = college degree) when compared to heads who only have some college.
> Estimate the difference in net worth (NETWORTH) between households whose heads have completed a college degree and heads with some college only (EDCL: 3 = some college, 4 = college degree)
> Refer to Exercise 15.48. The survey was performed in Canada, Australia, New Zealand, and the United Kingdom. Is there enough evidence to infer that there are differences in adult cigarette smoking between the four Commonwealth countries? Data from Exerc
> Is there sufficient evidence to infer that there are differences in total unrealized capital gains (KGTOTAL) between heads of households who finished high school and those who did not (EDCL:1 = No high school diploma, 2 = High school diploma)?
> Estimate the difference in income between heads of households who did finish high school (EDCL: 1 = no high school diploma, 2 = high school diploma) and those who did not (INCOME).
> Incomes of people who work for themselves are likely more variable than people who work for someone else. That’s because incomes for someone who is self-employed range from $0 to virtually unlimited. a. Is there sufficient evidence that middle class head
> Estimate the difference in total household debt between self-employed (OCCAT1: 1 = someone else, 2 = self-employed/partnership) and heads of households who work for someone else (DEBT).
> Is there enough evidence to conclude that households whose heads have some college (EDCL: 3 = some college, 4 = college degree) have less debt (DEBT) than households whose heads completed a college degree?
> Do people who completed a college degree fare better financially than those who started college but never finished? One way to judge financial success is by measuring assets. Is there enough evidence to conclude that heads of households with college degr
> (HHSEX: 1 = Male, 2 = Female). For each variable, test to determine whether there is enough evidence to conclude that men and women differ. Household has at least one late payment in the previous year (LATE: 0 = No, 1 = Yes).
> (HHSEX: 1 = Male, 2 = Female). For each variable, test to determine whether there is enough evidence to conclude that men and women differ. Household has incurred debt (HDEBT: Household has any debt: 0 = No, 1 = Yes)
> (HHSEX: 1 = Male, 2 = Female). For each variable, test to determine whether there is enough evidence to conclude that men and women differ. Household has declared bankruptcy in the previous 5 years (BNKRUPTLAST5: 0 = No, 1 = Yes).
> (HHSEX: 1 = Male, 2 = Female). For each variable, test to determine whether there is enough evidence to conclude that men and women differ. Household has been turned down for credit in the previous 5 years (TURNDOWN: 0 = No, 1 = Yes).
> To measure the extent of cigarette smoking around the world, random samples of adults in Denmark, Finland, Norway, and Sweden were drawn. Each was asked whether he or she smoked (2 = Yes, 1 = No). Can we conclude that there are differences in smoking bet
> (HHSEX: 1 = Male, 2 = Female). For each variable, test to determine whether there is enough evidence to conclude that men and women differ. Household overall expenses over last 12 months (EXPENSHILO: 1 = Unusually high, 2 = Unusually low, 3 = Normal).
> (HHSEX: 1 = Male, 2 = Female). For each variable, test to determine whether there is enough evidence to conclude that men and women differ. Industry classification for head of household (INDCAT: 1 = Mining 1 construction 1 manufacturing, 2 = Transportati
> (HHSEX: 1 = Male, 2 = Female). For each variable, test to determine whether there is enough evidence to conclude that men and women differ. Education category of head of household EDCL: 1 = No high school diploma, 2 = High school diploma, 3 = Some colleg
> (RACE: 1 = White, non-Hispanic, 2 = Black/African American, 3 = Hispanic, 5 = Other). For each variable, test to determine whether there is sufficient evidence to conclude that differences exist between the four races. Household has at least one late pay
> (RACE: 1 = White, non-Hispanic, 2 = Black/African American, 3 = Hispanic, 5 = Other). For each variable, test to determine whether there is sufficient evidence to conclude that differences exist between the four races. Household has incurred debt (HDEBT:
> (RACE: 1 = White, non-Hispanic, 2 = Black/African American, 3 = Hispanic, 5 = Other). For each variable, test to determine whether there is sufficient evidence to conclude that differences exist between the four races. Household has declared bankruptcy i
> (RACE: 1 = White, non-Hispanic, 2 = Black/African American, 3 = Hispanic, 5 = Other). For each variable, test to determine whether there is sufficient evidence to conclude that differences exist between the four races. Household has been turned down for
> (RACE: 1 = White, non-Hispanic, 2 = Black/African American, 3 = Hispanic, 5 = Other). For each variable, test to determine whether there is sufficient evidence to conclude that differences exist between the four races. House ownership (HOUSECL: 1 = Owns,
> (EDCL Education category of head of household: 1 = No high school diploma, 2 = High school diploma, 3 = Some college, 4 = College degree) with respect to several demographic and financial variables. For each variable, test to determine whether there are
> (EDCL Education category of head of household: 1 = No high school diploma, 2 = High school diploma, 3 = Some college, 4 = College degree) with respect to several demographic and financial variables. For each variable, test to determine whether there are
> A statistics practitioner took random samples from Canada, Australia, New Zealand, and the United Kingdom, and classified each person as either obese (2) or not (1). Can we conclude from these data that there are differences in obesity rates between the
> (EDCL Education category of head of household: 1 = No high school diploma, 2 = High school diploma, 3 = Some college, 4 = College degree) with respect to several demographic and financial variables. For each variable, test to determine whether there are
> (EDCL Education category of head of household: 1 = No high school diploma, 2 = High school diploma, 3 = Some college, 4 = College degree) with respect to several demographic and financial variables. For each variable, test to determine whether there are
> Can we infer from the data that there are differences in the total unrealized capital gains (KGTOTAL) between the three industry classifications?
> Can we infer from the data that there are differences in the amount of debt (DEBT) between the three industry classifications?
> Can we infer from the data that there are differences in net worth (NETWORTH) between the heads of households whose jobs are in one of the three industry classifications?
> Are some industries better than others in terms of financial remuneration? Conduct a test to determine whether there are differences in income (INCOME) between the three categories of industry.
