A company manufacturing computer chips finds that 8% of all chips


6.  A company manufacturing computer chips finds that 8%  of all chips manufactured are defective. In an effort to decrease the percentage of defective chips, management decides to provide additional training to those employees hired within the last year. After training was implemented, a sample of 450 chips revealed only 27 defects. A hypothesis test is performed to determine if the additional training was effective in lowering the defect rate. Suppose the p-value associated with the test statistic is 0.0594. For a = .01, what is the correct conclusion?

Don't use plagiarized sources. Get Your Custom Essay on
A company manufacturing computer chips finds that 8% of all chips
Just from $13/Page
Order Essay

 

a)      The additional training significantly increased the defect rate.

b)      The additional training significantly lowered the defect rate.

c)       The additional training did affect the defect rate.

d)      The additional training did not significantly lower the defect rate.

e)      None of these.

 

 

 

7. In the 1980’s, it was generally beloved that congenital abnormalities affected about 7% of a large nation’s children. Some people believe that the increase in the number of chemicals in the environment has led to an increase in the incidence of abnormalities. A recent study examined 398 randomly selected children and found that 41 of them showed signs of an abnormality. Is this strong evidence that the risk has increased?

(We consider a P-value of around 5% to represent reasonable evidence).

 

Complete a through f.

 

A)     Write appropriate hypothesis. Let P be the proportion of children with genetic abnormalities. Choose the correct answer below.

 

a)     

b)     

c)      

d)     

e)     

 

B)      Check the necessary assumptions. Which of the following are satisfied?

 

a)      The data are independent.

b)      There are more than 10 successes & 10 Failures.

c)       Less than 10%  of the population was sampled.

d)      The sample is random

 

C)      Perform the mechanics of the test. What is the P-value?

P-value = 0.005(Round  up to 3 decimal places).

 

D)     Explain carefully what the P-value means in this context. Choose the correct answer.

 

 

a)      The P-value is the actual percentage of children who have genetic abnormalities.

b)      The P-value is the chance of observing 41 or more children with genetic abnormalities in a random sample of 398 children if 7% of children actually have genetic abnormalities.

c)       The P-value is the chance of observing 7% of children with genetic abnormalities.

d)      The P-value is the chance of observing 41 or more children with genetic abnormalities in a random sample of 398 children.

 

E)      What’s your conclusion?

a)      Fail to reject Ho. There is sufficient evidence that more than 7% of the nation’s children have genetic abnormalities.

b)      Fail to reject Ho. There is not sufficient evidence that more than 7% of the Nation’s children have genetic abnormalities.

c)       Reject Ho. There is not sufficient evidence that more than 7% of the nation’s children have genetic abnormalities.

d)      Reject Ho. There is sufficient evidence that more than 7% of the nation’s children have genetic abnormalities.

 

 

F)      Do environmental chemicals cause congenital abnormalities?

a)      No, the conclusion of the hypothesis test shows that environmental chemicals do not cause genetic abnormalities.

b)      Yes, the conclusion of the hypothesis test shows that environmental chemicals cause genetic abnormalities.

c)       It is unknown if environmental chemicals cause genetic abnormalities, because the hypothesis test does not indicate the cause of any changes.

 

 

8) A survey of 350 students is selected randomly on a large university campus. They are asked if they use a laptop in class to take notes. Suppose that based on the survey, 140 of the 350 students responded “yes”.

 

a)      What is the values of the sample proportion p^ ?

 

b)      What is the standard error of the sample proportion?

 

c)       Construct an approximate 95% confidence interval for the true proportion p by taking ± 2 SEs from the sample proportion.

 

a)      P^ = 0.4 (type an integer or a decimal)

b)      The standard error of the sample proportion is 0.0262

c)       The approximate 95% confidence interval for the true proportion p by taking ± 2 SEs from the sample proportion is 0.348,0.452 (round to 3 decimal places)

 

 

9) A biotechnology firm is planning its investment strategy for future products and research labs. A poll found that 12% of a random sample of 1034 adults approved of attempts to clone a human. Use this information to complete parts a through E.

 

A)     Find the margin of error for this poll if we want 99% confidence in our estimate of the percent of adults who approves of cloning humans.

 

ME = 0.026(ROUND TO 3 DECIMAL PLACES)

 

 

B)      Explain what the margin of error means:

a)      The pollsters are 99% confident that the margin of error contains the true proportion of adults who approve of attempts to clone a human.

b)      The margin of error is the width of the confidence interval that contains the true proportion of adults who approve of attempts to clone a human

c)       The pollsters are 99% confident that the true proportion of adults who approve of attempts to clone a human is within the margin of error of the estimated 12%

d)      The mean of error is the value that should be subtracted from the 99% confidence level to obtain the pollsters true confidence level.

 

C)      If we only need to be 95% confident, will the margin of error be larger or smaller?

a)      A 95% confidence interval requires a larger margin and error. In order to increase confidence, the interval must be wider.

b)      A 95% confidence interval requires a smaller margin of error. A narrower interval leads to decrease confidence.

 

 

D)     Find that margin of error.

ME = 0.20

 

 

E)      In general, if all other aspects of the situation remain the same, would smaller samples produce small or larger margin of error?

a)      Smaller samples produce smaller margins of error.

b)      Smaller samples produce larger margins of error.

 

10) For parts a & b, use the t tables, software, or calculator to estimate.

 

A)     The critical value of  t for a 99% confidence interval with df=20 is 2.85 Round to 2 decimal places.

B)      The critical value of t for a 90% confidence interval with df=62 is 1.67 Round to two decimal places.

 

Get 20% Discount on This Paper
Pages (550 words)
Approximate price: -

Try it now!

Get 20% Discount on This Paper

We'll send you the first draft for approval by at
Total price:
$0.00

How it works?

Follow these simple steps to get your paper done

Place your order

Fill in the order form and provide all details of your assignment.

Proceed with the payment

Choose the payment system that suits you most.

Receive the final file

Once your paper is ready, we will email it to you.

Our Services

Australia Assessments has gained an international reputation of being the leading website in custom assignment writing services. Once you give us the instructions of your paper through the order form, we will complete the rest.

Essays

Essay Writing Services

As we work towards providing the best custom assignment services, our company provides assignment services for any type of academic essay. We will help you develop professionally written essays that are rich in content and free from plagiarism.

Admissions

Admission and Business Papers

Our skilled team of professional writers will ensure that we help you craft a remarkable admission essay for your desired Master's program in your institution of choice. We won't stop there. Once you enter the job market, we will be available to secure you a position at your desired worksite by creating an outstanding portfolio or resume.

Editing

Editing and Proofreading

Our editorial team is always available for all editing and proofreading services. They check completed papers by our writers and also provide professional opinions to papers completed by our clients.

Coursework

Technical papers

We harbor professional academic writers with different qualifications in diverse academic fields. As such, we are capable of handling both simple and technical papers. Ensure that you provide us with correct and complete instructions in the order form.