Q.4. For each of the following conditions answer the following questions: 1. National statistics data showed that teenagers on the average lose 20 school days per year due to infections. A researcher wanted to test the hypothesis that hand washing would reduce this average, he sampled 100 teenagers who wash their hands appropriately and calculated their average school absence days after one year. What Test of hypothesis should be used? Justification for the use of the test: Write down the Research problem: 2. The average body mass index (BMI) for young girls in Palestine is 22 with a standard deviation of 2. A researcher claims that girls with certain nutritional habits would have a higher average. The researcher sampled 50 young girls who follows such habits and measured their BMI to test the claim. His sample produced an average of 24 and a standard deviation of 2.
What type of hypothesis testing should be used in this condition? Ho: What is the 95% confidence interval for the true mean? 3. To find out if people vaccinated with vaccine A has a higher antibody titer than people vaccinated with vaccine B an independent sample of 50 persons was vaccinated by each vaccine and their average antibody titer was measured to test the hypothesis. Group receiving vaccine A had an average 16, while the second group B had a mean of 12. If the titer values in the two populations are normally distributed then: What test of hypothesis has to be used for this condition? Justification for the test ue: What is the critical value of the test? H