Surgery and germs. Joseph Lister (for whom Listerineis named!) was a British physician who was interestedin the role of bacteria in human infections. He suspectedthat germs were involved in transmitting infection, so hetried using carbolic acid as an operating room disinfectant.In 75 amputations, he used carbolic acid 40 times. Of the40 amputations using carbolic acid, 34 of the patientslived. Of the 35 amputations without carbolic acid,19 patients lived. The question of interest is whethercarbolic acid is effective in increasing the chances ofsurviving an amputation.a) What kind of a study is this?b) What do you conclude? Support your conclusion bytesting an appropriate hypothesis.c) What reservations do you have about the design ofthe study?

Question 6  In a study with a total of 200 people, you have determined that typists have an incidence of 25 per 100  (25%) of carpal tunnel syndrome compared to only 5 per 100 (5%) of people employed in professional,  white-collar occupations. This was a 2-year follow-up study and there was no loss to follow-up. All  subjects in the study were free from carpal tunnel syndrome at the beginning of the study. Use the following information to set up a 2 x 2 table and calculate appropriate measure of association. b) Draw the 2x2 table and complete the table.

Q2.1 Hypotheses In a clinical trial to compare the effectiveness of two drugs in preventing heart attacks, 25,620 patients were randomly divided into three groups. One group took a tablet of drug A each day. The next group took a table of drug B each day. The third group took one table of each drug each day. Patients were studied for 56 months and the number of who suffered heart attacks (fatal and non-fatal) were counted. Write the appropriate hypotheses to test if there would be an association between these treatments and cardiac outcome. Save Answer Q2.2 Conditions Values in the table represent counts, (expected values), and [Chi-square components] for this study. Drug A Drug B Both drugs Save Answer Is the sample size of 25,620 large enough? Explain how you know. Q2.3 Mechanics Fatal Heart Attack 598 (607.14) [0.1376] 603 (609.56) [0.0706] 620 (604.30) [0.4079] Drug A Drug B Both drugs Values in the table represent counts, (expected values), and [Chi-square components] for this…

According to the American Red Cross, out of every 100 people in the United States, blood types and Rh factors occur at the rates shown in the tabl Blood Type O+ O- A+ А- В+ В- AB+ AB- Occurrence 36 7 34 6 11 2 3 1 (a) Of all people in the United States who have type B blood, what percent are Rh positive? (Round the answer to one decimal place.) 84 % (b) Of all people in the United States who have type B blood, what percent are Rh negative? (Round the answer to one decimal place.) 16 X %

Need 7.S.7

QUESTION 13 The test for screening donated blood for the presence of the AlDS virus was developed in the 1980s. It is designed to detect antibodies, substances produced by the body of donors carrying the virus, however it is not 100% accurate. The developer of the test claimed that the test would produce fewer than 5% false positives and fewer than 1% false negatives. In order to evaluate the accuracy of the test 1000 persons known to have AlDS and 10,000 persons known to not have aids were given the test. The following results were tabulated: True State of Patient Test Result Has Aids Does Not Have Aids Total Positive Test 997 530 1,527 Negative Test 3. 9,470 9,473 Total 1.000 10,000 000

You are running an online business that requires boxes and bubble wrap for postage purpose. Lets say you got the boxes and bubble wrap from four different suppliers, each of the suppliers represent 25% of your supply. Some of the boxes and bubble wrap you received are poor in quality and not meeting the specification. You would like to investigate which suppliers that supply good items and which are not. Based on the table below, generate randomly value Al to A4 and B1 to B4 from 0 to 1 in decimal form. Then, based on the values generated, determine what is the value of A’l to A'4 and B’1 to B'4. Table 1: Condition of box and bubble wrap for Company – Company 4 Supplier Percentage of supply Item A: BOX Item B: BUBBLE WRAP Good Not Good Good Not Good (%) Company 1 25 A1 A’ı B1 B'1 Company 2 25 A2 A'2 B2 B'2 Company 3 Company 4 25 Аз A'3 Вз B'3 25 A4 A'4 B4 B'4 i. Based on the data from Table 1, suppose that a box is in a poor-quality condition, calculate the probability it comes from…

T=5, T, = 10, T3 =15, with SS1 = 6, SS2=9, SS3 = 9, and EX² = 94. For this study, what is SSwithin?

Wild irises are beautiful flowers found throughout the United States, Canada, and northern Europe. This problem concerns the length of the sepal (leaf-like part covering the flower) of different species of wild iris. Data are based on information taken from an article by R. A. Fisher in Annals of Eugenics (Vol. 7, part 2, pp. 179 -188). Measurements of sepal length in centimeters from random samples of Iris setosa (I), Iris versicolor (II), and Iris virginica (III) are as follows below. I II III 5.9 5.8 6.9 4.8 6.5 5.6 4.6 6.4 4.9 5.7 4.3 7.7 4.8 5.8 5.6 5.4 6.3 6.3 5.8 5.5     6.6   Shall we reject or not reject the claim that there are no differences among the population means of sepal length for the different species of iris? Use a 5% level of significance.   (b) Find SSTOT, SSBET, and SSW and check that SSTOT = SSBET + SSW. (Use 3 decimal places.) SSTOT =   SSBET =   SSW =   Find d.f.BET, d.f.W, MSBET, and MSW. (Use 4 decimal places for MSBET, and…

QUESTION 5 An experiment was conducted to evaluate the effectiveness of a treatment for tapeworm in the stomachs of sheep. A random sample of 60 worm-infected lambs of approximately the same age and health was randomly divided into two groups. Thirty of the lambs were injected with the drug and the remaining thirty were left untreated. After a 6-month period, the lambs were slaughtered and the number of worms in the lamb of the stomach were counted. The drug-treated sheep had a mean of 24.67 worms with a standard deviation of 13.78. The untreated sheep had a mean of 37.82 worms with a standard deviation of 18.21. Assuming the true variances cannot be assumed equivalent, which of the following would be the correct way to calculate a t test for a two-tailed hypothesis test? OA. 24.67-37.82 O B. о с. t ¹0= 13.78 18.21 30 30 24.67-37.82 + (13.78) 2 30 + 24.67-37.82 + (18.21) ² 30 13.78 18.21 60 60 + 24.67-37.82 (13.78) 2 60 (18.21) 2 60