In: Statistics and Probability
Using traditional methods it takes 110.0 hours to receive a basic driving license. A new license training method using Computer Aided Instruction (CAI) has been proposed. A researcher used the technique on 50 students and observed that they had a mean of 111.0 hours. Assume the variance is known to be 16.00. Is there evidence at the 0.05 level that the technique performs differently than the traditional method? Step 1 of 5: Enter the hypotheses: Step 3 of 5: Specify if the test is one-tailed or two-tailed. Step 4 of 5: Enter the decision rule. Step 5 of 5: Enter the conclusion.
Ans.
Step1:
, it take 110 hrs to receive a basic driving license.
,
it does not take 110 hrs to receive a basic driving license.
Step 2:
It is a two-tailed test.
As in the question it is mention that a new license technique effect differently on the hours to receive driving license, there is nowhere in question mention that this new technique increase or decrease the hours to receive a basic driving license.
Also when we write a , in a alternate
hypothesis, it does mean that we are doing a two-tailed test.
Step 3:
Now we have to calculate the test statistic for our hypothesis
in order to reject or FTR(fail to reject) our
.
The for we use for this is :
It tells us that
now using a t-table for two tailed we need to find the value
for, significance level
, with
degree of freedom(df=n-1).
If we find
Then we
are FTR(fail to reject)
.
Then we reject the
, which we found the evidence that
is likely to be
true.
Using t-table we found for
and
for
for two
tail is:
So we found that our is
less than our
i.e., 1.768<2.021
Step 4:
As we find out that
So we are
FTR(fail to reject) our Null Hypothesis
.
It implies that we not have evidence to believe that the
Alternate hypotheis is true
and the new Computer Aided Instruction(CAI) method does not have
any effect in the hours that it take to receive a basic driving
license.