In: Statistics and Probability
The mayor of a town has proposed a plan for the construction of an adjoining community. A political study took a sample of 1200 voters in the town and found that 45% of the residents favored construction. Using the data, a political strategist wants to test the claim that the percentage of residents who favor construction is not equal 48%. Testing at the 0.01 level, is there enough evidence to support the strategist's claim?
Step 1 of 7 : State the null and alternative hypotheses.
Step 2 of 7: Find the value of the test statistic. Round your answer to two decimal places.
Step 3 of 7: Specify if the test is one-tailed or two-tailed.
Step 4 of 7: Determine the P-value of the test statistic. Round your answer to four decimal places.
Step 5 of 7: Identify the value of the level of significance.
Step 6 of 7: Make the decision to reject or fail to reject the null hypothesis.
Step 7 of 7: State the conclusion of the hypothesis test.
Here we have given that,
n=number of voters in the town = 1200
= Sample proportion of voters in the town found that the residents favoured construction= 45%=0.45.
p=Population proportion of residents who favor constructions= 48%=0.48
Step 1 of 7:
Claim: To check whether the proportion of residents who favor constructions is not equal to 48% ( i.e. 0.48).
The null and alternative hypothesis are as follows,
Versus
where p is the proportion of residents who favor constructions
This is the two-tailed test.
Step 2 of 7:
Now, we can find the test statistic is as follows,
Z-statistics=
=
= -2.08
The test statistics is -2.08.
Step 3 of 7:
This is the two-tailed test as our interest is to see the proportion of residents who favor constructions is not equal to 48%.
Step 4 of 7:
Now we find the P-value,
p-value=2* P(Z < z-statistics) as this is two tailed test
=2* P( Z < -2.08)
=2* 0.01876 Using standard normal z table see the value corresponding to the z=-3.36
=0.0375
The p-value is 0.0375
Step 5 of 7:
= level of significance= 0.05
Step 6 of 7:
Decision:
Here p-value (0.0375) less than (<) 0.05
We reject the Ho (Null Hypothesis)
Step 7 of 7:
Conclusion:
There is sufficient evidence to conclude that the proportion of residents who favor constructions is not equal to 48% ( i.e. 0.48).