Question

1. The proportion of professional baseball players who take steroids has been assumed to be twenty percent by the team owner council. The Commissioner of Baseball has instituted a new campaign to reduce the proportion of players who take steroids.  The Commissioner would now like to test whether their campaign has worked. (α = 0.05)

State the null and alternative hypotheses that the Commissioner would test. Use symbols in the hypotheses. State alpha and define the parameter.

H_o:  p = 0.2  (.)        

      H_a:  p < 0.2 (.)                                 

2. Time Magazine states that the nationwide drop out rate for high school seniors is ten percent. You conduct a test to see if the drop out rate for high school seniors is actually more than ten percent. ( α = 0.01)

     State the null and alternative hypotheses for this test.  Use symbols in the hypotheses.  

     State alpha and define the parameter.

3. The Maryland Department of Health claims that the proportion of heroin users in Maryland that have been infected by HIV is four percent. Suppose a researcher wants to show that this claim is not true. ( α = 0.1)

     State the null and alternative hypotheses to dispute the Maryland Department of Health’s claim. Use symbols in the hypotheses.  State alpha and define the parameter.

H_o:         

   H_a:  

4. Time Magazine states that the drop out rate for high school seniors is ten percent. You conduct a test to see if the drop out rate for high school seniors is actually more than ten percent.  One hundred high school seniors were randomly selected to see whether they had dropped out.  The number of these high school seniors who dropped out is 15.  Calculate the test statistic.  (α = 0.05)

5. The Maryland Department of Health claims that the proportion of heroin users in Maryland that have been infected by HIV is four percent.  Suppose a researcher wants to show that this claim is not true.  The researcher randomly selects 1000 Maryland heroin users and finds that 80 have been infected with HIV.  Calculate the test statistic. (α =  0.1)

Answer 1