An ad for Crest Whitestrips Premium claims that the strips will whiten teeth in 7 days...

An ad for Crest Whitestrips Premium claims that the strips will whiten teeth in 7 days and the results will last for 12 months. A researcher who wishes to test this claim studies 20 sets of identical twins. Within each set of twins, one is randomly selected to use Crest Whitestrips Premium in addition to regular brushing and flossing, while the other just brushes and flosses. Whiteness of the teeth is measured at the beginning of the study, after 7 days, and every month thereafter for 12 months.
1. What type of experimental design is this?
1. What is the response variable in this experiment?
1. What are the treatments?
1. What are other factors (controlled or uncontrolled) that could affect the response variable?
1. What might be an advantage of using identical twins as subjects in this experiment?

Expert Solution

orchestra answered 1 year ago

Suppose an ad agency claims that likes per hour of their ad is not equal to...

Suppose an ad agency claims that likes per hour of their ad is not equal to 7 likes, on average. Several of their employees do not believe them, so a manager decides to do a hypothesis test, at a 5% significance level, to persuade them. She collects data for 19 hours and works through the testing procedure: H0: μ=7; Ha: μ≠7 x¯=6.2 σ=0.9 α=0.05 (significance level) The test statistic is z0=x¯−μ0σn√=6.2−70.919√=−3.87 The critical values are −z0.025=−1.96 and z0.025=1.96. Conclude whether...

A Treasury STRIPS matures in 7 years and has a yield to maturity of 11.9 percent....

A Treasury STRIPS matures in 7 years and has a yield to maturity of 11.9 percent. Assume the par value is $100,000. a. What is the price of the STRIPS? (Do not round intermediate calculations. Round your answer to 2 decimal places.) b. What is the quoted price? (Do not round intermediate calculations. Round your answer to 3 decimal places.)

Strike Price Maturity Premium $1.36/£ 30 days $0.00081/£ $1.34/£ 30 days $0.00021/£ $1.32/£ 30 days $0.00004/£...

Strike Price Maturity Premium $1.36/£ 30 days $0.00081/£ $1.34/£ 30 days $0.00021/£ $1.32/£ 30 days $0.00004/£ $1.36/£ 60 days $0.00333/£ $1.34/£ 60 days $0.00150/£ $1.32/£ 60 days $0.00060/£ Doyle Holmes is a currency trader for Watson Investments, a private investment house in London. Watson’s clients are a collection of wealthy private investors who, with a minimum stake of £250,000 each, wish to speculate on the movement of currencies. The investors expect annual returns in excess of 25%. Although offices are...

A pharmaceutical company claims that the average cold lasts an average of 8.4 days. They are...

A pharmaceutical company claims that the average cold lasts an average of 8.4 days. They are using this as a basis to test new medicines designed to shorten the length of colds. A random sample of 106 people with colds, finds that on average their colds last 8.28 days. The population is normally distributed with a standard deviation of 0.9 days. At α=0.02, what type of test is this and can you support the company’s claim using the p-value? Claim...

A manufacturer claims that the average tread life of a premium tire exceeds the average tread...

A manufacturer claims that the average tread life of a premium tire exceeds the average tread life of economy tire of the same size by at least 5000 miles. To test this claim, 50 pieces of each type of tires were tested under similar conditions. The premium tire had an average tread life of 43000 miles with a sample standard deviation of 2300, while economy tire had an average tread life of 37500 miles with a sample standard deviation of...

how to write 7 days diet analysis report?

The owner of a new car dealership claims the average number of days it takes his...

The owner of a new car dealership claims the average number of days it takes his dealership to sell a Chevrolet Aveo is 50 days. A random sample of 50 cars had a mean time on the dealer’s lot of 64 days. Assume the population standard deviation to be 7.0 days. Find the 95% confidence interval estimate of the population mean. State the Margin of Error, Best Point Estimate and Include the written statement Please list all the work.

Change in share price within 7 days of 7 May 2018 of Westpac: Track and report...

Change in share price within 7 days of 7 May 2018 of Westpac: Track and report any change in Westpac company's share price within 7 days of 7 May 2018(provide evidence of this change tracking). Change in share price within 7 days of 7 February 2018 of Commonwealth: Track and report any change in Commonwealth share price within 7 days of 7 February 2018. What information in the half yearly financial report may have caused this change? If there is...

An insurance company states that at least 85% of its claims are settled within 30 days.

4) (1 point) An insurance company states that at least 85% of its claims are settled within 30 days. A consumer group selected a random sample of 66 of the company's claims to test this statement. They found that 55 of the claims were settled within 30 days. Does the consumer group have evidence to disbelieve the insurance company's claim? 1. Write the hypotheses to test if the rate of claims settled within 30 days is less than 85%. H0H0:...

Someone claims that the mean number of sick days that employees in New Jersey take per...

Someone claims that the mean number of sick days that employees in New Jersey take per year is 5.3. To look into that claim, you take a representative sample of 78 employees in New Jersey and find that the mean number of sick days is 5.5 in the sample. The population standard deviation is 1.6. Part (a) Given that the sample mean is different from the claimed population mean, does that show that the claim in H0 is false?...

Question