Statistics

MA3110: Module 4 Hypothesis Testing

Exercise 4.2

Hypothesis Testing

1

Solve the following problems:

 Examine the given statement:

o The proportion of people aged 18–25 who currently use illicit drugs is equal to 0.20 (or

20%). Express the null hypothesis H0 and the alternative hypothesis H1 in symbolic form. Be

sure to use the correct symbols—μ, p, and σ—for the indicated parameter.

 Refer to the following data:

o Two-tailed test; 0.10

o Assume that the normal distribution applies and find the critical z values.

 Use the following information to find the P-value.

o The value of the test statistic for a right-tailed one mean z test is z = 2.50.

o Use a 0.05 significance level and state the conclusion about the null hypothesis—reject the

null hypothesis or fail to reject the null hypothesis.

 Test the claim: A simple random sample of 50 adults is obtained, and each person’s red blood cell

count (in cells per micro-liter) is measured. The sample mean is 5.23. The population standard

deviation for red blood cell counts is 0.54. Use a 0.01 significance level to test the claim that the

sample is from a population with a mean less than 5.4, which is a value often used for the upper

limit of the range of normal values. What do the results suggest about the sample group?

 Identify the null hypothesis, alternative hypothesis, test statistic, P-value or critical value(s),

conclusion about the null hypothesis, and the conclusion that addresses the original claim. Use the

P-value method.

Submission Requirements:

 Submit the assignment in a Microsoft Word or Excel document.

 Show detailed steps and provide appropriate rationale with your answers.

Evaluation Criteria:

 Correctly answered each question

 Included appropriate steps or rationale to determine the answer to each question