1. An auto company wanted to know the percentage of people who prefer to own safer...
1. An auto company wanted to know the percentage of people who prefer to own safer cars (that is, cars that possess more safety features) even if they have to pay a few thousand dollars more. A random sample of 500 people showed that 320 of them will not mind paying a few thousand dollars more to have safer cars.
Construct a 90% confidence interval for the percentage of people who will not mind paying a few thousand dollars more to have safer cars.
2. Tony’s Pizza guarantees all pizza deliveries within 30 minutes of the placement of orders. A preliminary study has shown that 93% of all Tony’s pizzas are delivered within 30 minutes. The sample size was 1084. What confidence interval was used if the maximum error was .02
3. An auto manufacturing company wants to estimate the variance of miles per gallon for its auto model AST727. A random sample of 24 cars of this model showed that the variance of miles per gallon for these cars is .58.
Construct the 95% confidence intervals for the population variance and standard deviation. Assume that the miles per gallon for all such cars are (approximately) normally distributed.
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1. An auto company wanted to know the percentage of people who
prefer to own safer...
Conduct a hypothesis test for each problem, using the traditional method. Show the 5 steps and al...
Conduct a hypothesis test for each problem, using the traditional method. Show the 5 steps and all work for each hypothesis test. Be sure you select the correct test to use for each problem. 1. A telephone company claims that less than 30% of all college students have a limited number of text messages per month. A random sample of 150 students revealed that 41 of them have a limited number. Test the company's claim at the 0.01 level of...
A tele-marketing company wants to know if sales go up as they call more people per...
A tele-marketing company wants to know if sales go up as they call more people per day but spend less time per call. The following is the data from nine randomly selected days. The information is the number of calls the salesperson makes in a day and the total amount of sales (in thousands of dollars) Calls 25 29 33 37 48 67 43 55 Sales 3.7 4.2 5.0 5.3 4.9 5.6 5.9 4.2 4.7 0.05, use a model test...
A sociologist is interested in the relation between x = number of job changes and γ = annual salary (in thousands of dollars) for people living in the Nashville area. A random sample of 10 people emp...
A sociologist is interested in the relation between x = number of job changes and γ = annual salary (in thousands of dollars) for people living in the Nashville area. A random sample of 10 people employed in Nashville provided the following information. 9 10 10 3 34 36 32 32 32 3843 37 40 33 5 76 x (number of job changes) Y (Salary in $1000 In this setting we have Σχ = 62, Ху-357, ΣΧ2-462, Xy2-12,875, and ΣΧγ...
Assignment 10 1. A random sample of 37 drivers insured with a company having similar auto...
Assignment 10 1. A random sample of 37 drivers insured with a company having similar auto insurance policies) was selected The data table lists each of the driver's driving experience in years (DU), and their monthly auto insurance pre- miums in dollars (CU). A researcher wished to determine the following: Correlation: Experience (yrs) 1. On an a priori basis, would the researcher expect a positive or negative inverse) relationship between years driving experience and monthly insurance pre- miums? 4 4...
Question 5 (1 point) Suppose you work for a marketing consulting firm and you are tasked...
Question 5 (1 point) Suppose you work for a marketing consulting firm and you are tasked to determine the proportion of Americans who respond positively to an ad your agency is testing for release. A survey is performed and you randomly select 134 respondents. You input your data into a statistical computing package (like Minitab) and you are given a 99% confidence interval of (0.3886 , 0.6114). You need to present these findings next departmental meeting. What is the correct...
PART I. Multiple Choice. Cirele the letter to the correct answer on the front page 1. Below is a ...
PART I. Multiple Choice. Cirele the letter to the correct answer on the front page 1. Below is a list of assumptions necessary for the regression analysis to be valid. With each assumption is a proposed procedure (on the right) for checking the validity of the assumption. Select the assumption validity which is the correct match. a. Normal errors b. Constant error variance C. Plot of residuals versus x Plot of residuals versus x Histogram of residuals Look for outliers...
PART I. Multiple Choice. Cirele the letter to the correct answer on the front page 1. Below is a ...
PART I. Multiple Choice. Cirele the letter to the correct answer on the front page 1. Below is a list of assumptions necessary for the regression analysis to be valid. With each assumption is a proposed procedure (on the right) for checking the validity of the assumption. Select the assumption validity which is the correct match. a. Normal errors b. Constant error variance C. Plot of residuals versus x Plot of residuals versus x Histogram of residuals Look for outliers...
STA2221 examples on CI & Testing of Hypothesis Name MULTIPLE CHOICE. Choose the one alternative that...
STA2221 examples on CI & Testing of Hypothesis Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answer the question Provide an appropriate response. 1) Find the critical value,te for 0.99 and n-10. A) 3.250 B) 3.169 1.833 D) 2.262 2) Find the critical value to forc=0.95 and n=16. A) 2.947 B) 2.602 2120 D) 2.131 3) Find the value of E, the margin of error, for A) 1.69 B) 0.42 0.99, n=16 and s=2.6. C)...
1. A hypothetical investigation on rider satisfaction with a particular public transit system serving commuting residents...
1. A hypothetical investigation on rider satisfaction with a particular public transit system serving commuting residents of British California (BC) and Prince Edward’s County (PEC) offers some interesting findings. The proportion of commuters from BC that indicated low satisfaction with the transit system’s service in the 2018 calendar year was 65 percent, and the proportion from PEC was 70 percent. These point estimates were based on samples of 5,380 BC commuters and 6,810 PEC commuters, whose system-using commuters number in...
Case study Company Case Campbell Soup Company: Watching What You Eat You might think that a well-known, veteran consumer products company like the Campbell Soup Company has it made. After all, when pe...
Case study Company Case Campbell Soup Company: Watching What You Eat You might think that a well-known, veteran consumer products company like the Campbell Soup Company has it made. After all, when people think of soup, they think of Campbell’s. In the $5 billion U.S. soup market, Campbell dominates with a 44 percent share. Selling products under such an iconic brand name should be a snap. But if you ask Denise Morrison, CEO of Campbell, she’ll tell you a different...
A tele-marketing company wants to know if sales go up as they call more people per day but spend less time per call. The following is the data from nine randomly selected days. The information is the number of calls the salesperson makes in a day and the total amount of sales (in thousands of dollars) Calls 25 29 33 37 48 67 43 55 Sales 3.7 4.2 5.0 5.3 4.9 5.6 5.9 4.2 4.7 0.05, use a model test...
A sociologist is interested in the relation between x = number of job changes and γ = annual salary (in thousands of dollars) for people living in the Nashville area. A random sample of 10 people employed in Nashville provided the following information. 9 10 10 3 34 36 32 32 32 3843 37 40 33 5 76 x (number of job changes) Y (Salary in $1000 In this setting we have Σχ = 62, Ху-357, ΣΧ2-462, Xy2-12,875, and ΣΧγ...
Assignment 10 1. A random sample of 37 drivers insured with a company having similar auto insurance policies) was selected The data table lists each of the driver's driving experience in years (DU), and their monthly auto insurance pre- miums in dollars (CU). A researcher wished to determine the following: Correlation: Experience (yrs) 1. On an a priori basis, would the researcher expect a positive or negative inverse) relationship between years driving experience and monthly insurance pre- miums? 4 4...
Question 5 (1 point) Suppose you work for a marketing consulting firm and you are tasked to determine the proportion of Americans who respond positively to an ad your agency is testing for release. A survey is performed and you randomly select 134 respondents. You input your data into a statistical computing package (like Minitab) and you are given a 99% confidence interval of (0.3886 , 0.6114). You need to present these findings next departmental meeting. What is the correct...
PART I. Multiple Choice. Cirele the letter to the correct answer on the front page 1. Below is a list of assumptions necessary for the regression analysis to be valid. With each assumption is a proposed procedure (on the right) for checking the validity of the assumption. Select the assumption validity which is the correct match. a. Normal errors b. Constant error variance C. Plot of residuals versus x Plot of residuals versus x Histogram of residuals Look for outliers...
PART I. Multiple Choice. Cirele the letter to the correct answer on the front page 1. Below is a list of assumptions necessary for the regression analysis to be valid. With each assumption is a proposed procedure (on the right) for checking the validity of the assumption. Select the assumption validity which is the correct match. a. Normal errors b. Constant error variance C. Plot of residuals versus x Plot of residuals versus x Histogram of residuals Look for outliers...
STA2221 examples on CI & Testing of Hypothesis Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answer the question Provide an appropriate response. 1) Find the critical value,te for 0.99 and n-10. A) 3.250 B) 3.169 1.833 D) 2.262 2) Find the critical value to forc=0.95 and n=16. A) 2.947 B) 2.602 2120 D) 2.131 3) Find the value of E, the margin of error, for A) 1.69 B) 0.42 0.99, n=16 and s=2.6. C)...
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