# Module 25 Homework 1

## Progress Check

Use this activity to assess whether you and your peers can:

• Use summarized data to conduct a chi-square test of independence and interpret the conclusion in context.

## Directions

Use the drop-down menu to learn about the three steps needed to complete this assignment.

Three steps to complete the assignment

## Context – A Real Court Case

In the early 1970s, a young man challenged an Oklahoma state law that prohibited the sale of 3.2% beer to males under age 21 but allowed its sale to females in the same age group. The case (Craig v. Boren, 429 U.S. 190, 1976) was ultimately heard by the U.S. Supreme Court. The state of Oklahoma argued that the law improved traffic safety. One of the three main pieces of data presented to the court was the result of a random roadside survey. This survey gathered information on gender and whether or not the driver had been drinking alcohol in the previous 2 hours. A total of 619 drivers under 21 years of age were included in the survey.

## Prompt

1. A test of independence may be appropriate if we are examining the relationship between two categorical variables in one population. For this situation what is the population? What is the explanatory variable? What is the response variable?
2. What are the hypotheses for the Test of Independence? State hypotheses with reference to the context of the scenario.
3. The spreadsheet of the data looked like this:
Driver Gender Alcohol in last
two hours?
Driver 1 M Yes
Driver 2 F No
Driver 3 F Yes
.
.
.
.
.
.
.
.
.
Driver 619 M No

We will not use the raw data. Instead, we will use the summarized data shown in the table below.

Drank alcohol in last 2 hours? Male Female Yes No Totals 77 404 481 16 122 138 93 526 619

Use StatCrunch to find expected counts, the Chi-square test statistic, and the P-value. ()
Copy and paste your StatCrunch table into the textbox.

4. How many males in the sample are expected to answer yes to questions about alcohol consumption in the last two hours? Show how to calculate this expected count and explain what it means relative to the hypotheses.
5. Explain how we know that this data meets the conditions for use of a chi-square distribution.
6. State a conclusion at a 5% level of significance. Do you think that the data supports the Oklahoma law that forbids the sale of 3.2% beer to males and permits it to females?

## Optional Discussion Board

Use the Module 25 (opens in a new tab) to ask questions or provide feedback about the problems in any Module 25 activity – including this peer-reviewed assignment.

## Review Feedback

• Instructor feedback is only available after an assignment is graded.
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Content by Cuyamaca College math faculty and licensed under the .

## Rubric

Formative Assessments w/ StatCrunch

Formative Assessments w/ StatCrunch

Criteria Ratings Pts