Question

The mayor of a town has proposed a plan for the annexation of an adjoining community. A political study took a sample of 1000 voters in the town and found that 54% of the residents favored annexation. Using the data, a political strategist wants to test the claim that the percentage of residents who favor annexation is more than 50%. Determine the P-value of the test statistic. Round your answer to four decimal places.

Answer 1

`z=\frac{0.54 -0.5}{\sqrt{(0.5(1-0.5))/(1000)}}=2.530`

`p_v =P(z>2.530)=0.0057`

Explanation:

Data given and notation

n=1000 represent the random sample taken

`\hat p=0.54` estimated proportion of residents that favored the annexation

`p_o=0.5` is the value that we want to test

z would represent the statistic (variable of interest)

`p_v` represent the p value (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that the true proportion is higher than 0.5:

Null hypothesis:
`p \leq 0.5`

Alternative hypothesis:
`p > 0.5`

When we conduct a proportion test we need to use the z statistic, and the is given by:

`z=\frac{\hat p -p_o}{\sqrt{(p_o (1-p_o))/(n)}}` (1)

The One-Sample Proportion Test is used to assess whether a population proportion
`\hat p` is significantly different from a hypothesized value
`p_o`.

Calculate the statistic

Since we have all the info required we can replace in formula (1) like this:

`z=\frac{0.54 -0.5}{\sqrt{(0.5(1-0.5))/(1000)}}=2.530`

Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The next step would be calculate the p value for this test.

Since is a right tailed test the p value would be:

`p_v =P(z>2.530)=0.0057`