Exam 12: Infectious Conditions

Nationwide Insurance would like to perform a chi- square test to investigate whether a difference exists in the proportion of male and female teenagers who text while they drive. A random sample of 80 male teenagers found that 50 indicated they texted while driving. A random sample of 120 female teenagers found that 65 indicated they texted while driving. The degrees of freedom for the chi- square critical value is ______.

Nationwide Insurance would like to perform a chi- square test to investigate whether a difference exists in the proportion of male and female teenagers who text while they drive. A random sample of 80 male teenagers found that 50 indicated they texted while driving. A random sample of 120 female teenagers found that 65 indicated they texted while driving. Using α = 0.5, the conclusion for this chi- square test would be that because the test statistic is

When using the chi- square hypothesis test and the observed frequencies are relatively close to the expected frequencies, which one of the following statements is true?

The _____ frequencies refer to the frequencies that are most likely to occur if the null hypothesis is true when performing a hypothesis test comparing two or more population proportions.

Nationwide Insurance would like to perform a chi- square test to investigate whether a difference exists in the proportion of male and female teenagers who text while they drive. A random sample of 80 male teenagers found that 50 indicated they texted while driving. A random sample of 120 female teenagers found that 65 indicated they texted while driving. The chi- square test statistic for this sample is ______.

When the chi- square test statistic is greater than the chi- square critical value when comparing two or more population proportions, we fail to reject the null hypothesis.

For a chi- square test of independence, the expected frequencies are permitted to be less than 5.

Nationwide Insurance would like to perform a chi- square test to investigate whether a difference exists in the proportion of male and female teenagers who text while they drive. A random sample of 80 male teenagers found that 50 indicated they texted while driving. A random sample of 120 female teenagers found that 65 indicated they texted while driving. The chi- square critical value using α = 0.5 is ______ .

When testing for a normal distribution with the chi- square goodness- of- fit test with a sample size of 30 observations, the number of intervals needed to satisfy the minimum number of expected frequencies is ________ .

Nationwide Insurance would like to perform a chi- square test to investigate whether a difference exists in the proportion of male and female teenagers who text while they drive. A random sample of 80 male teenagers found that 50 indicated they texted while driving. A random sample of 120 female teenagers found that 65 indicated they texted while driving. The expected frequency of male teenagers who text is _______.

When testing for a normal distribution with the chi- square goodness- of- fit test with a sample size of 50 observations, the number of intervals needed to satisfy the minimum number of expected frequencies is _____-_ .

The chi- square test for independence is used to decide if observed frequencies follow a known probability distribution.

When performing a hypothesis test to compare two or more population proportions, the expected frequencies must always be integer values.

Two variables are dependent if changes in the levels of one variable do not affect the levels of the other variable.

When testing for a normal distribution with the chi- square goodness- of- fit test with a sample size of 100 observations, the number of intervals needed to satisfy the minimum number of expected frequencies is _______ .

The chi- square test of independence does not allow us to state that one variable causes a change in another variable when the null hypothesis is rejected.

When we reject the null hypothesis for a chi- square test of independence, we are concluding that there is no relationship between the two variables.

The chi- square test requires that each expected frequency be equal to or greater than _____.

The chi- square goodness- of- fit test is used to determine if two categorical variables are independent of one another.

The shape of the chi- square distribution is left- skewed.