Question

A laboratory is testing a new vaccine against virus Z. It is administered to 500 subjects...

A laboratory is testing a new vaccine against virus Z. It is administered to 500 subjects (treatment group). Another 500 subjects were selected and given no vaccine (control group). After 5 months, they found that 20 subjects from the treatment group and 70 subjects from the control group were infected with the virus Z.

(A) What's the probability of getting the virus if no vaccine was given? Calculate the confidence interval of the estimate. (Use 95% C.I.)

(B) If the laboratory wants to prove the vaccine reduces the risk of infection, what hypothesis should they use to test it? Calculate the p-value for that hypothesis.

(C) What conclusion can be drawn from the p-value found in part (B)?

*Note: Use two sample proportion hypothesis

Homework Answers

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Common colds are typically caused by a rhinovirus. In a test of effectiveness of Echinacea, some...
Common colds are typically caused by a rhinovirus. In a test of effectiveness of Echinacea, some test subjects were treated with Echinacea extracted with 20% ethanol, some were treated with Echinacea extracted with 60% ethanol, and others were given a placebo. All of the test subjects were then exposed to rhinovirus. Results are summarized in Table given below. Use a 0.05 significance level to test the claim that getting an infection (cold) is independent of the treatment group. What does...
Listed below are the body lengths (in inches) and weights (in lb) of randomly selected bears:...
Listed below are the body lengths (in inches) and weights (in lb) of randomly selected bears: Length 40         64         65         49         47 Weight 65        356       316        94         86 Find the value of the linear correlation coefficient. Letting y represent weights of bears and letting xrepresent their lengths, find the regression equation. Based on the given sample data, what is the best predicted weight of a bear with a length of 72.0 inch ? Common colds are typically caused by a...
Ear infections A new vaccine was recently tested to see if it could prevent the painful...
Ear infections A new vaccine was recently tested to see if it could prevent the painful and recurrent ear infections that many infants suffer from. The Lancet, a medical journal, reported a study in which babies about a year old were randomly divided into two groups. One group received vaccinations; the other did not. During the following year, only 333 of 2455 vaccinated children had ear infections, compared to 499 of 2452 unvaccinated children in the control group. Does it...
Ear infections A new vaccine was recently tested to see if it could prevent the painful...
Ear infections A new vaccine was recently tested to see if it could prevent the painful and recurrent ear infections that many infants suffer from. The Lancet, a medical journal, reported a study in which babies about a year old were randomly divided into two groups. One group received vaccinations; the other did not. During the following year, only 333 of 2455 vaccinated children had ear infections, compared to 499 of 2452 unvaccinated children in the control group. Does it...
A high-risk group of 803 male volunteers was included in a major clinical trial for testing...
A high-risk group of 803 male volunteers was included in a major clinical trial for testing a new vaccine for type B hepatitis. The vaccine was given to 320 persons randomly selected from the group, and the others were injected with a neutral substance (placebo). 13 of the vaccinated people and 30 of the nonvaccinated ones later got the disease. We wish to test the hypothesis that the probability of getting type B hepatitis is different (higher or lower) for...
A new vaccine was recently tested to see if it course prevent the painful and recurrent...
A new vaccine was recently tested to see if it course prevent the painful and recurrent ear infections that many infants suffer from. The Lancet, a medical journal, reported a study in which babies about a year old were randomly divided into two groups. One group received vaccinations the other did not. During the following year, 333 of 2455 vaccinated children had ear infections, compared to 499 of 2452 unvaccinated children in the control group.    Did this study provide...
An experiment was conducted to test the effect of a new drug on a viral infection....
An experiment was conducted to test the effect of a new drug on a viral infection. After the infection was induced in 100 mice, the mice were randomly split into two groups of 50. The first group, the control group, received no treatment for the infection, and the second group received the drug. After a 30-day period, the proportions of survivors, p?1 and p?2, in the two groups were found to be 0.38 and 0.66, respectively. (a) Is there sufficient...
Suppose that 600 students we selected at random from a student body and given a vaccine...
Suppose that 600 students we selected at random from a student body and given a vaccine to prevent a certain type of flu. The campus reported cases of the flu so the students were exposed. A follow-up survey found that 562 of them did not get the flu. a. Calculate the sample estimate of the proportion of the shot being successful. b. Construct a 95% confidence interval around the sample estimate. This is a proportion and all the information you...
A high-risk group of 814 male volunteers was included in a major clinical trial for testing...
A high-risk group of 814 male volunteers was included in a major clinical trial for testing a new vaccine for type B hepatitis. The vaccine was given to 367 persons randomly selected from the group, and the others were injected with a neutral substance (placebo). 16 of the vaccinated people and 37 of the nonvaccinated ones later got the disease. We wish to test the hypothesis that the probability of getting type B hepatitis is different (higher or lower) for...
It is claimed that a new treatment is more effective than the standard treatment for prolonging...
It is claimed that a new treatment is more effective than the standard treatment for prolonging the lives of terminal cancer patients. The standard treatment has been in use for a long time, and from records in medical journals, the mean survival period is known to be 4.2 years. The new treatment is administered to 80 patients and their duration of survival recorded. The sample mean and the standard deviation are found to be 4.5 and 1.1 years, respectively. Answer...