nteered to take part in the study. - Design how you would carry out the experiment, what tasks the participants should perform, and define what could be a null and alternative hypothesis in this case. - Describe what could be an error of type I or type II, how they are defined theoretically and what they represent in this case.

A machine has to be repaired if there are more than 10% defectives among all items it produces in a day. A random sample of 100 items for the day’s production contains 15 defectives. The manager needs to decide whether the machine must be repaired or not. Please design an appropriate hypothesis test to help the manager make this decision. The significant level of the test is 0.05. If you only have a random sample of 10 items and find 2 defectives among these items, what is your suggestion? The significant level is 0.05 too.

A recent drug survey showed an increase in the use of drugs and alcohol among local high school seniors as compared to the national percentage. Suppose that a survey of 100 local seniors and 100 national seniors is conducted to see if the proportion of drug and alcohol use is higher locally than nationally. Locally, 65 seniors reported using drugs or alcohol within the past month, while 60 national seniors reported using them. Conduct a hypothesis test at the 5% level.NOTE: If you are using a Student's t-distribution for the problem, including for paired data, you may assume that the underlying population is normally distributed. (In general, you must first prove that assumption, though.) Part (a) State the null hypothesis. H0: plocal ≠ pnational H0: plocal > pnational      H0: plocal = pnational H0: plocal < pnational Part (b) State the alternative hypothesis. Ha: plocal < pnational Ha: plocal = pnational      Ha: plocal ≠ pnational Ha: plocal > pnational…

Using traditional methods it takes 105 hours to receive an advanced driving license. A new training technique using Computer Aided Instruction (CAI) has been proposed. A researcher believes the new technique may reduce training time and decides to perform a hypothesis test. After performing the test on 50 students, the researcher fails to reject the null hypothesis at a 0.02 level of significance. What is the conclusion?