Chapter 13 Self-Grading Quizzes

. Which of these is a characteristic of a normal distribution?

It is bilaterally symmetrical.

The tails of the curve meet the horizontal axis at 1.

The area is equal to 2.

Almost call cases fall within two standard deviations of the mean.

. The central limit theorem states that the distribution of the means of random samples taken from a population approaches the normal distribution as _________.

the population size increases.

the sample size decreases.

the sample size increases.

the deviation decreases.

. The _____________ is the probability that a sample statistic is an accurate reflection of the population parameter, while the _____________ is the range in which the population parameter is likely to fall.

margin of error; residual variance

confidence interval; margin of error

confidence interval; confidence level

confidence level; confidence interval

. The ______ is a parametric test.

chi-square

t-test for differences between means

two-tailed test

Mann-Whitney U-test

. When examining the relationship between a nominal variable to a normally distributed interval-ratio variable, you would use _____________.

chi-square

ANOVA

A t-test

Mann-Whitney U-test

. Before calculating chi-square, we must construct a ______.

table of variables

content table

contingency table

confidence level table

. For the chi-square, t-test, and F-test, determining the critical value requires calculating the ___________.

contingency table

degrees of freedom

number of variables

difference of means

. Multiple regression analysis is used when ______.

there is not enough data to carry out simple linear regression analysis

the dependent variable depends on more than one independent variable

one or more of the assumptions of simple linear regression are not correct

the relationship between the dependent variable and the independent variable cannot be described by a linear function

. The following is NOT a major assumption of multiple regression analysis: ______.

The independent variables are independent of one another.

The regression line exhibits a constant error across the values of the independent variables.

The independent variables are dependent on one another.

The data are measured at the interval level.

. Logistic regression is used rather than multivariate regression when ____________.

there are multiple independent variables.

the independent variable is ordinal.

the dependent variable is interval-ratio.

the dependent variable is not interval-ratio.

. Many real world variables are distributed according to the normal distribution.

True

False

. Only statistically significant results are ever substantively significant.

True

False

. Chi-square tests the independence of two variables by assessing the likelihood that the relationship observed in the sample is due to chance.

True

False

. The difference of means test compares rankings, while the Mann-Whitney U-test compares means.

True

False

. One implication of the central-limit theorem is that, as sample size decreases, the distribution of cases more closely approximates a normal curve.

True

False

. If your hypothesis implies that you are interested only in one direction of difference between your samples, then you should use a two-tailed test.

True

False

. A dummy variable typically is characterized by the presence and the absence of a quality.

True

False

. Multicollinearity refers to the existence of a relationship between a study's independent variables, which generally violates the linear regression assumption that independent variables should be unrelated to one another.

True

False

Quiz Content