Sociologists want to test whether the number of homeless people in a particular urban area is increasing. In 2010, the average number of homeless people per day who sought shelter was 42.3 (σ = 6.2). Data from the current year reveal that the mean number of people seeking shelter per day is 45.3. Compute the test statistic using an alpha = .01 and n = 1000.

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Answer:

The test statistic value is 15.3.

Step-by-step explanation:

The hypothesis for this test is:

H₀: The average number of homeless people is not increasing, i.e. μ = 42.3.

Hₐ: The average number of homeless people is increasing, i.e. μ > 42.3.

Given:

[tex]\bar x=45.3\\\sigma=6.2\\n=1000[/tex]

As the population standard deviation is provided use a single mean z-test for the hypothesis testing.

The test statistic is:

[tex]z=\frac{\bar x-\mu}{\sigma/\sqrt{n}}=\frac{45.3-42.3}{6.2/\sqrt{1000}}=15.3[/tex]

Thus, the test statistic value is 15.3.

Using the z-distribution, it is found that the test statistic is of z = 15.3.

At the null hypothesis, it is tested if the mean number has not increased, that is, it still is of 42.3, hence:

[tex]H_0: \mu = 42.3[/tex]

At the alternative hypothesis, it is tested if it has increased, that is, the mean is greater than 42.3, hence:

[tex]H_1: \mu > 42.3[/tex]

We have the standard deviation for the population, hence, the z-distribution is used.

The test statistic is:

[tex]z = \frac{\overline{x} - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

The parameters are:

  • [tex]\overline{x}[/tex] is the sample mean.
  • [tex]\mu[/tex] is the value tested at the null hypothesis.
  • [tex]\sigma[/tex] is the standard deviation of the sample.
  • n is the sample size.

For this problem, the values of the parameters are:

[tex]\overline{x} = 45.3, \mu = 42.3, \sigma = 6.2, n = 1000[/tex]

Hence:

[tex]z = \frac{\overline{x} - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \frac{45.3 - 42.3}{\frac{6.2}{\sqrt{1000}}}[/tex]

[tex]z = 15.3[/tex]

The test statistic is of z = 15.3.

To learn more about the z-distribution, you can take a look at https://brainly.com/question/16313918