Question 1

Results of statistical tests that achieve the level of significance allow a researcher (and readers) to _____________ a study's null hypothesis.

Accepted Answer

A)   Accept.
B)   Prove.
C)   Reject. C

Question 2

A researcher wants to test the difference between average weights of a group of nursing home residents before and after a new food service program is put in place. Which statistical test should be used in this situation?

Accepted Answer

A)   Chi-squared.
B)   Dependent samples t-test.
C)   Repeated measures ANOVA. B

Question 3

What does a correlation coefficient describe?

Accepted Answer

A)   Central tendency of a distribution.
B)   Direction and strength of a relationship.
C)   Variability of a distribution. B

Question 4

The mean test scores for three groups are 22.35, 25.75, and 30.35. The researcher examines these scores using ANOVA; results are F = 3.16 (2, 57), p = 0.04. Based on these results, the researcher can conclude

Accepted Answer

A)   there is a difference in the mean scores for these three groups.
B)   there is no difference in the mean scores for these three groups.
C)   groups 1 and 2 are significantly different from group 3.

Question 5

A researcher collects data on education and codes it as follows:
1 = less than high school
2 = high school completion or GED
3 = some post-high school education
4 = AA degree or completion of trade school
5 = BA or equivalent
6 = graduate education
The most appropriate measure of central tendency for these data would be the

Accepted Answer

A)   mean.
B)   median.
C)   mode.

Question 6

Which of the following statistical indices is best for describing the heterogeneity of values in a data set?

Accepted Answer

A)   Mean.
B)   Range.
C)   Standard deviation.

Question 7

If the distribution of values for a data set is characterized by very few high values and a preponderance of low values, it would be described as

Accepted Answer

A)   negatively skewed.
B)   positively skewed.
C)   normal.

Question 8

A correlation coefficient of -0.20 for the variables weight and age would indicate a slight tendency for

Accepted Answer

A)   older individuals to weigh more.
B)   younger individuals to weigh more.
C)   younger individuals to weigh less.

Question 9

What does a researcher's level of significance represent?

Accepted Answer

A)   Likelihood of committing a Type I error.
B)   Likelihood of committing a Type II error.
C)   Likelihood of detecting clinically significant differences.

Question 10

A researcher uses analysis of covariance (ANCOVA) to compare dependency scores of men and women in different jobs, holding constant their age. Which variable is the covariate in this situation?

Accepted Answer

A)   Age.
B)   Gender.
C)   Job.

Question 11

The relationship between gender and specialty area among nurses could be described by using which of the following procedures?

Accepted Answer

A)   Contingency table.
B)   Pearson's r.
C)   t-test.

Question 12

A researcher wants to compare differences in hospital length of stay for preterm infants who are randomly assigned to four different methods of stimulation. Which statistical test should be used in this situation?

Accepted Answer

A)   ANCOVA.
B)   Factorial ANOVA.
C)   One-way ANOVA.

Question 13

Which of the following statements is true?

Accepted Answer

A)   Decreased risk of a Type I error is associated with a decreased risk of a Type II error.
B)   Risk of a Type I error is lower with a 0.01 level of significance than with a 0.05 level of significance.
C)   Statistically nonsignificant results mean that the null hypothesis is true.

Question 14

Which of the following correlation coefficients denotes the strongest relationship?

Accepted Answer

A)   -0.50.
B)   0.05.
C)   0.25.

Question 15

A researcher wants to compare NCLEX scores for students from ADN and BSN programs in two states. The most appropriate statistical test for this situation would be

Accepted Answer

A)   Chi-squared.
B)   factorial ANOVA.
C)   independent t-test.

Question 16

If a researcher sets the level of significance at 0.05, the null hypothesis can be rejected if the p value associated with the test statistic is

Accepted Answer

A)   0.04.
B)   0.06.
C)   0.10.

Question 17

A researcher commits a Type I error when

Accepted Answer

A)   a null hypothesis that is false is rejected.
B)   a null hypothesis that is true is rejected.
C)   there is failure to reject a false null hypothesis.

Question 18

In a research article, r is reported as 0.48. This indicates what type of relationship?

Accepted Answer

A)   Relatively weak.
B)   Moderate.
C)   Statistically significant.

Question 19

Which value for Pearson's r is most likely to be clinically significant?

Accepted Answer

A)   r = -0.20, p = 0.06.
B)   r = 0.25, p = 0.05.
C)   r = 0.50, p = 0.01.

Question 20

Multiple regression could be used to examine which of the following?

Accepted Answer

A)   Effect of age and preoperative stress level on patients' heart rate.
B)   Effect of age and preoperative stress on the presence versus absence of surgical complications.
C)   Effect of preoperative stress on heart rate and blood pressure readings.

Exam 12: Data Analysis in Quantitative Research