Two-Way Table Inference (11.2)

The National Longitudinal Study of Adolescent Health interviewed a random sample of 4877 teens (grades 7 to 12).  One question asked was "What do you think are the chances you will be married in the next ten years?"  A two-way table of the response by gender is provided.  Which of the following would be the most appropriate type of graph for these data?

• A bar chart showing the marginal distribution of opinion about marriage.
• A bar chart showing the marginal distribution of gender.
• A bar chart showing the conditional distribution of gender for each opinion about marriage.
• A bar chart showing the conditional distribution of opinion about marriage for each gender.

The National Longitudinal Study of Adolescent Health interviewed a random sample of 4877 teens (grades 7 to 12).  One question asked was "What do you think are the chances you will be married in the next ten years?"  A two-way table of the response by gender is provided.  The appropriate null hypothesis for performing a chi-square test is that

• there is no difference between the distributions of female and male teenagers' opinions about marriage in this sample.
• there is no difference between the distributions of female and male teenagers' opinions about marriage in the population.
• there is no association between gender and opinion about marriage in the sample.
• there is no association between gender and opinion about marriage in the population.

The National Longitudinal Study of Adolescent Health interviewed a random sample of 4877 teens (grades 7 to 12).  One question asked was "What do you think are the chances you will be married in the next ten years?"  A two-way table of the response by gender is provided.  The expected count of females who respond "almost certain" is

• 487.7
• 525
• 965
• 1038.8

The National Longitudinal Study of Adolescent Health interviewed a random sample of 4877 teens (grades 7 to 12).  One question asked was "What do you think are the chances you will be married in the next ten years?"  A two-way table of the response by gender is provided.  The degrees of freedom for the chi-square test for this two-way table are

• 4
• 8
• 10
• 20

The National Longitudinal Study of Adolescent Health interviewed a random sample of 4877 teens (grades 7 to 12).  One question asked was "What do you think are the chances you will be married in the next ten years?"  A two-way table of the response by gender is provided.  For these data, χ² = 69.8 with a P-value of approximately 0.  Assuming the researchers used a significance level of 0.05, which of the following is true?

• A type I error is possible.
• A type II error is possible.
• There is no chance of making a type I or type II error because the P-value is approximately 0.
• There is no chance of making a type I or type II error because the calculations are correct.

When analyzing survey results from a two-way table, the main distinction between a test for independence and a test for homogeneity is

• how the degrees of freedom are calculated.
• the number of samples obtained.
• the number of columns in the two-way table.
• the number of rows in the two-way table.