biostats exam 3

The test statistic used for the Kruskal-Wallis test follows which distribution? A) the chi-square distribution with (k-1) degrees of freedom B) the t distribution with (k-1) degrees of freedom C) the F distribution with (1,k-1) degrees of freedom D) the standard normal distribution

A) the chi-square distribution with (k-1) degrees of freedom

What is the minimum number of groups that can be observed using the one-way between subjects ANOVA design? A) 1 B) 2 C) 3 D) 4

B) 2

A post-hoc test that can be used following a significant Kruskal-Wallis test is: A) Tukey's LSD test B) Bono U2 test C) Dunns Q test D) Duncin's HSD test

C) Dunns Q test

ANOVA stands for, A) analysis of variety B) analysis of variable attributes C) analysis of variance D) association of novel operating variable analyses

C) analysis of variance

A researcher notes that the variability attributed to difference between group means is quite large. Which source of variation is the researcher referring to? A) between-persons B) within-groups C) between-groups D) error

C) between-groups

The degrees of freedom for error is called A) degrees of freedom error B) degrees of freedom denominator C) degrees of freedom within-groups D) all of the above

D) all of the above

Which of the following is an assumption for computing a one-way between-subjects ANOVA? A) The population being sampled from is normally distributed. B) Participants were selected to participate using a random procedure. C) One observation has no effect on the likelihood of another observation. D) all of the above

D) all of the above

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

40. 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 Kruskal-Wallis test relies on: A) ranked data B) raw data C) mean values D) all of the above

A) ranked data

Which of the following post hoc tests is associated with the greatest power to detect an effect? A) Schaffé test B) Tukey's HSD test C) Bonferroni test D) Fisher's LSD test

D) Fisher's LSD test

Which of the following is not a post hoc test for a one-way between-subjects ANOVA? A) F test for equal variance B) Fisher's LSD test C) Tukey's HSD test D) Bonferroni test

A) F test for equal variance

Computing a one-way between-subjects ANOVA is appropriate when A) different participants are observed one time in each of two or more groups for one factor. B) the same participants are observed in each of two or more groups for one factor C) the levels of one or more factors are manipulated D) all of the above

A) different participants are observed one time in each of two or more groups for one factor.

Without changing the value of error variance, the ________ the between-groups variability, the more likely we are to reject the null hypothesis. A) larger B) smaller C) more homogeneous D) less spread

A) larger

When the variability attributed to between- groups is equal to the variability attributed to error, then the value of the test statistic for a one-way between-subjects ANOVA is, A) Equal to 0. B) Equal to 1. C) Significant at any sample size. D) Undefined in that the test statistic cannot be computed in this case.

B) Equal to 1.

Suppose a correlation is computed in each of two samples. If the value of SSXY is the same in each sample, and √SSXSSY is larger in Sample 1, then in which sample will the value of the correlation coefficient be larger? A) Sample 1 B) Sample 2 C) None; the correlation coefficient will be the same in both samples. D) There is not enough information to answer this question.

B) Sample 2

Which of the following post hoc tests is associated with the least power to detect an effect? A) Fisher's LSD test B) Tukey's HSD test C) Studentized Newman-Keuls D) None; each post hoc test is associated with the same power to detect an effect.

B) Tukey's HSD test

39. The correlation coefficient ranges from -1.0 to +1.0, with values closer to ±1.0 indicating A) a more positive relationship between two factors B) a stronger relationship between two factors C) that two factors are less likely to be related D) that the correlation is due to outliers

B) a stronger relationship between two factors

The denominator of the correlation coefficient measures the extent to which two variables A) vary together B) vary independently C) covary D) both A and C

B) vary independently

The source of variability associated with error variance in the one-way between-subjects ANOVA is called A) between-groups variability B) within-groups variability C) degrees of freedom D) both A and B

B) within-groups variability

Following a significant one-way between-subjects ANOVA in which k > 2, what is the next appropriate step? A) Summarize the data; no further tests are required. B) Interpret the data; no further tests are required. C) Conduct post hoc tests. D) both A and B

C) Conduct post hoc tests.

Post hoc tests are computed A) Prior to conducting a hypothesis test. B) To determine which set of degrees of freedom can be attributed to the variability between-groups. C) Following a significant ANOVA test to make pairwise comparisons. D) to determine if groups means differ, even for tests in which the decision is to retain the null hypothesis.

C) Following a significant ANOVA test to make pairwise comparisons.

A researcher divides participants into groups that will engage in low, moderate, or intense levels of exercise. The total calories consumed by participants following the exercise are then recorded. What type of statistical design is appropriate for this study? A) a related samples t test B) a two-independent sample t test C) a one-way between-subjects ANOVA D) both B and C

C) a one-way between-subjects ANOVA

The Kruskal-Wallis test can be used to: A) compare a ranked outcome by race group (W, AA, Other). B) compare a skewed continuous variable by a categorical variable with four levels. C) compare an interval/ratio variable across more than two groups D) All of the above

D) All of the above

The correlation coefficient is used to measure the ________ and ________ of the linear relationship between two factors. A) date;time B) mean; variance C) significance;effect size D) strength;direction

D) strength;direction

For an analysis of variance, the term "one-way" refers to A) the number of factors in the design B) the number of statistical tests in the design C) the number of ways that the data can be analyzed D) the direction that traffic should follow on a road

A) the number of factors in the design

The term "between-subjects" refers to A) observing the same participants in each group B) observing different participants one time in each group C) the type of post hoc test conducted D) the type of effect size estimate measured

B) observing different participants one time in each group

The Kruskal-Wallis test is the nonparametric analog to the A) one sample z test for a single population mean. B) two independent samples t test. C) one-way ANOVA F test. D) paired t test.

C) one-way ANOVA F test.

The numerator of the correlation coefficient measures the extent to which two variables A) vary together B) vary independently C) covary D) both A and C

D) both A and C vary together covary

What is the problem with the following data for computing a correlation? Factor 1 Factor 2 3 3 3 3 3 3 3 3 3 3 A) The correlation coefficient will equal 0 because it violates the assumption of normality. B) The correlation coefficient will equal 1.0 because it violates the assumption of normality. C) The correlation coefficient will equal 0 because it violates the assumption of linearity. D) The correlation coefficient will equal 1.0 because it violates the assumption of linearity

A) The correlation coefficient will equal 0 because it violates the assumption of normality.

The correlation coefficient measures the extent to which changes in one factor are _______ in a second factor. A) related to changes B) causing changes C) causing variability D) all of the above

A) related to changes

Homogeneity of variance is an assumption for the one-way between-subjects ANOVA. What does this assumption mean? A) that the population being sampled from is normally distributed B) that participants are randomly selected to participate in a sample C) that the variance is equal in each population from which samples are selected D) that one observation has no effect on the likelihood of another observation

C) that the variance is equal in each population from which samples are selected

The null hypothesis for the Kruskal-wallis test is A) the difference in ranks for the groups do not differ B) the median values for the groups do not differ C) the sum of the ranks in each group do not differ D) the sum of the ranks in each group do differ

C) the sum of the ranks in each group do not differ

The degrees of freedom for the between-groups variability is called A) degrees of freedom numerator B) degrees of freedom denominator C) degrees of freedom between-groups D) both A and C

D) both A and C degrees of freedom numerator degrees of freedom between-groups

A lowercase k is used to denote A) the number of groups in a study B) the number of participants in a study C) the number of levels of the factor in a study D) both A and C

D) both A and C the number of groups in a study the number of levels of the factor in a study