In: Statistics and Probability
#1: Using traditional methods it takes 100 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 190 students, the researcher fails to reject the null hypothesis at a 0.02 level of significance.
#2:
The director of research and development is testing a new drug. She wants to know if there is evidence at the 0.05 level that the drug stays in the system for more than 320 minutes. After performing a hypothesis test, she decides to reject the null hypothesis.
What is the conclusion?
#1)
Since a researcher believes the new technique may reduce training time,
Null hypothesis, H0 : new technique does not reduce training time(i.e., remains the same)
Alternate Hypothesis, Ha : new technique reduces the training time
And since the researcher fails to reject the null hypothesis at a 0.02 level of significance we conclude that new technique does not reduce training time.
Conclusion :
we conclude that new technique does not reduce training time at 0.02 level of significance.
#2)
Since, the researcher wants to know if there is evidence at the 0.05 level that the drug stays in the system for more than 320 minutes,
Null hypothesis H0 : the drug does not stays in the system for more than 320 minutes.
Alternate Hypothesis, Ha : the drug stays in the system for more than 320 minutes.
Since, she decides to reject the null hypothesis. The conclusion is, the drug does stay in the system for more than 320 minutes.