Exam #5
True or False: The predictor variable is a known value that is used to predict the value of another.
True
T or F: The predictor variable is a known value that is used to predict the value of another variable.
True
Which of the following is an example of a nonparametric test? a) analysis of variance b) the t-tests c) chi-square test d) Pearson correlation
Not b. c?
A researcher tests whether levels of education and income levels are related. In this study, he observes the following frequencies. If he computes a chi-square test for independence at a .05 level of significance, then what is the decision for this test? High School/Low Income: 22 Bachelor's/Low Income: 8 Grad/Low Income: 5 High School/High Income: 8 Bachelor's/High Income: 12 Grad/High Income: 28 a) Education and income level are related. b) Education and income level are not related. c) Education and income level are independent. d) Both B and C are appropriate.
a) Education and income level are related.
A researcher selects a sample of 80 people and records the frequency of participants choosing a low, moderate, or high calorie dessert in a buffet. What are the degrees of freedom for this chi-square goodness-of-fit test? a. 2 b. 3 c. 79 d. 80
a. 2
The phi correlation coefficient is a measure for the direction and strength of the linear relationship between two _____________ variables: a. dichotomous b. curvilinear c. ordinal d. significant
a. dichotomous
The degrees of freedom for a chi-square goodness-of-fit test are: a. k-1 b. n-1 c. (-1)(-1) d. (k-1)(n-1)
a. k-1
A local ice cream shop wants to see if they should promote a new swizzleberry swirl or creamsicle flavored drink. In order to determine which one to promote, they took a sample of 80 patrons and asked them to choose which they preferred. The one that is significantly preferred over the other (at a .05 level of significance) will be promoted. It is expected that an equal number of patrons will choose each flavor. Based on the observed frequencies given below, what is the decision for this test? Observed: Swizzleberry: 28 Creamsicle: 52 a) Promote the swizzleberry swirl flavored drink. b) Promote the creamsicle flavored drink. c) Do not promote any flavored drinks. d) There is not enough information to answer this question.
b) Promote the creamsicle flavored drink.
One key advantage for including multiple predictor variables in the equation of a regression line is that it allows you to: a. detect mean differences between groups for each criterion variable b. detect the extent to which two or more predictor variables interact c. show cause-and-effect because many predictor variables are added d. all of the above
b. detect the extent to which two or more predictor variables interact
The Spearman rank-order correlation coefficient is a measure of the direction and strength of the linear relationship between two ________ variables. a. nominal b. ordinal c. interval d. ratio
b. ordinal
The Spearman rank-order correlation coefficient is a measure of the direction and strength of the linear relationship between two ____________ variables. a. nominal b. ordinal c. interval d. ration
b. ordinal
A researcher measures the extent to which years of marriage predict perceptions of forgiveness. Which factor is the criterion variable in this example? a. years of marriage b. perceptions of forgiveness c. both years of marriage and perceptions of forgiveness d. none of the above
b. perceptions of forgiveness
Which of the following statements is true regarding the sources of variation present in an analysis of regression? a. regression variation measures variability in X, whereas residual variation measures variability in Y. b. the closer that data points fall to the regression line, the more the variance in Y will be attribution to regression variation. c. There are three sources of variation in an analysis of regression: regression variance, residual variance, and error variance. d. When most of the variability in Y is associated with residual variation, then X predicts Y.
b. the closer that data points fall to the regression line, the more the variance in Y will be attribution to regression variation.
The most common measure of effect size for the correlation coefficient is called: a. the correlation coefficient b. the coefficient of determination c. estimated Cohen's d d. the test statistic
b. the coefficient of determination
The appropriate correlation coefficient for measuring the direction and strength of the linear relationship between one continuous and one dichotomous variable is a. the Spearman rank-order correlation coefficient b. the point-biserial correlation coefficient c. the phi correlation coefficient d. none of the above
b. the point-biserial correlation coefficient
The appropriate correlation coefficient for measuring the direction and strength of the linear relationship between one continuous and one dichotomous variable is: a. the Spearman rank-order correlation coefficient b. the point-biserial correlation coefficient c. the phi correlation coefficient d. none of the above
b. the point-biserial correlation coefficient
The more that the variability in ____ is associated with regression variation, the more likely it is that X predicts Y. a. XY b. X c. Y d. all of the above
c. Y
The more that the variability in ________________ is associated with regression variation, the more likely it is that X predicts Y. a. XY b. X c. Y d. all of the above
c. Y
Both sources of variation in an analysis of regression measure the variability in: a. X and Y b. X only c. Y only
c. Y only
Both sources of variation in an analysis of regression measure the variability in: a. X and Y b. X only c. Y only
c. Y only
The standard error of estimate is used as a measure of the ________________ in predictions using the equation of a regression line. a. linearity b. appropriateness c. accuracy d. certainty
c. accuracy
Which of the following is an example of a nonparametric test? a. analysis of variance b. the t-test c. chi-square test d. Pearson correlation
c. chi-square test
The assumption that there is an equal variance or scatter of data points dispersed along the regression line is referred to as: a. normality b. linearity c. homoscedasticity d. restriction of range
c. homoscedasticity
Which of the following indicates the strongest correlation? a. r = -0.57 b. r = +0.78 c. r = -0.90 d. r = +0.88
c. r = -0.90
Which of the following indicates the strongest correlation? a. r=-0.57 b. r=+0.78 c. r=-0.90 d. r=+0.88
c. r=-0.90
The normality assumption states that the population of X and Y scores form a bivariate ("two variable") normal distribution, such that: a. the population of X and Y scores are normally distributed b. for each X score, the distribution of Y scores is normally distributed c. for each Y score, the distribution of X scores is normally distributed d. all of the above
d. all of the above
Which of the following is an appropriate measure of effect size for a 2 x 2 chi-square test for independence? a. proportion of variance b. the phi coefficient c. Cramer's V d. all of the above
d. all of the above
Which of the following is recorded using a chi-square goodness-of-fit test and a chi-square test for independence? a. variance b. frequency observed c. frequency expected d. both B and C
d. both B and C
Which of the following is used to determine the linear equation that best fits a set of data points? a. correlational analysis b. analysis of variance c. analysis of regression d. method of least squares
d. method of least squares
True or False: A positive correlation is always stronger than a negative correlation.
false
True or False: Parametric tests are often called distribution-free tests.
false
True or False: The chi-square test is an example of a parametric test.
false
True or False: The equation for a straight line is Y=bx + a
true
True or False: The formula for the chi-square test measures the size of the discrepancy between observed and expected frequencies.
true
True or False: The phi coefficient can be used to estimate the effect size of a 2 x 2 chi-square test for independence?
true