Deck 12: Bivariate Statistics and Statistical Inference

Question 1

Which involves making a calculated decision based on the results of an observation by employing mathematical calculation of the odds?

A) Logical inference.
B) Calculus decision making.
C) Mathematical model.
D) Statistical inference.

Answer 1

D

Question 2

A statistical inference is based on which of the following?

A) The knowledge of the social worker.
B) Probability.
C) Computer technology.
D) Advanced mathematics.

Answer 2

B

Question 3

Determining the likelihood that the findings from sample data are real is referred to as:

A) Probability testing.
B) Data testing.
C) Reality testing.
D) Statistical significance testing.

Answer 3

D

Question 4

The null hypothesis is a statement that there is:

A) No relationship or difference.
B) A statistically significant relationship.
C) A testable research question.
D) A relationship or a difference.

Question 5

The alternative or research hypothesis is a statement that:

A) There is a relationship or a difference.
B) Is identical to the research question.
C) Includes the association of two concepts.
D) There is a probability of truth.

Question 6

Which of the following represents a null hypothesis?

A) There is no difference between the baseline mean and the treatment mean.
B) There is a "real" relationship between income and mental health.
C) The sample has a case of sample error.
D) All of the above.

Question 7

Statistical significance testing is a process:

A) Of employing an inductive framework to uncover the truth.
B) Whereby we determine the probability that our findings are the result of sample error.
C) That has a p value that is greater than 90%.
D) When the null hypothesis is accepted.

Question 8

A p-value is the probability:

A) Of a type two error.
B) That a relationship/difference found in a sample is a result of sample error.
C) Of accepting the null hypothesis.
D) All of the above.

Question 9

By statistical significance, we mean:

A) Proof that the research hypothesis is true.
B) That the results cannot be proven false.
C) The result is not likely to be due to sample error.
D) The truth has been uncovered.

Question 10

Which of the following represents a Type I error?

A) Rejecting the null hypothesis when the null hypothesis is true.
B) Rejecting the null hypothesis when the null hypothesis is false.
C) Failing to reject the null hypothesis when the null hypothesis is true.
D) Failing to reject the null hypothesis when the null hypothesis is false.

Question 11

Which is a Type II error?

A) Rejecting the null hypothesis when the null hypothesis is true.
B) Rejecting the null hypothesis when the null hypothesis is false.
C) Failing to reject the null hypothesis when the null hypothesis is true.
D) Failing to reject the null hypothesis when the null hypothesis is false.

Question 12

Statistical significance testing is most appropriate:

A) When the data are from a random sample.
B) If a quota sample is used.
C) When a survey is taken.
D) All of the above.

Question 13

Research designs that involve randomization are rare in social work because of:

A) Expense.
B) Little practical application.
C) Ethical objections.
D) Knowledge.

Question 14

If the sample is not truly random:

A) The significance test can overstate the accuracy of the results.
B) The population must become the sample.
C) The sample must be extremely high.
D) The null hypothesis cannot be rejected.

Question 15

Parametric statistics are used when:

A) At least one of the two variables being analyzed is measured at the interval or ratio level.
B) The data are normally distributed in the population.
C) The mean, median, and mode are roughly equal.
D) All of the above.

Question 16

Nonparametric statistics are used for analyzing:

A) Data that are normally distributed in the population.
B) Data at the nominal level of measurement.
C) The mean, median, and mode are roughly equal.
D) None of the above.

Question 17

Which of the following correlation coefficients is the strongest?

A) -.70
B) .02
C) .35
D) .52

Question 18

A straight line drawn though the points on a scatter plot so that one half of the points are above the line and one half are below it is called:

A) A perfect correlation.
B) The line of best fit.
C) An r between .9 and 1.0.
D) The scatter plot line.

Question 19

A moderate correlation or substantial relationship is represented by which of the following?

A) Less than .20
B) .20 - .40
C) .40 - .70
D) .70 - .90

Question 20

The minimum expected value for each chi square cell is:

A) 1
B) 5
C) 10
D) 100

Question 21

A professor wants to know if students learn as well taking an online course versus a face-to-face course. The online class has 21 students while the face-to-face class has 16 students. The professor wants to know if the averages between the same final exams are significantly different. What statistic should be used?

A) Independent samples t-test.
B) Paired t-test.
C) One sample t-test.
D) ANOVA.

Question 22

An administrator of a TANF program is concerned about the length of time hard-to-place clients were able to gain employment. He wants to contrast the average length of time at a job for his clients with the national average. What statistic should he use?

A) Independent samples t-test.
B) Paired t-test.
C) One sample t-test.
D) ANOVA.

Question 23

What involves calculating the probability of committing a Type II error based on the type of test, the sample size, and an estimate of the strength of the relationship?

A) Null hypothesis testing.
B) Statistical power analysis.
C) Test of significance.
D) p-value analysis.

Question 24

Explain the relationship between statistical significance testing and probability.

Question 25

Develop a simple research question appropriate for hypothesis testing; state the null hypothesis, a nondirectional or two-tailed hypothesis; and a directional or one-tailed hypothesis.

Question 26

Several difference p-values are listed below; identify which one is considered statistically significant according to typical standards in social work research, then briefly discuss what this value actually means.
.75
.50
.03
.21
.13

Question 27

Briefly describe when parametric statistics are appropriate and when nonparametric statistics are appropriate.

Question 28

A social worker conducts a research study and finds that two variables have a Pearson's r of -.45. What does this value indicate regarding the strength and the direction of the relationship between these two values?

Question 29

Using the following data, construct a cross tabulation table comparing BSW students and MSW students in terms of their value of gerontology in social work education (value or do not value). Simple addition and subtraction is necessary.
Total BSW students = 125
Total MSW students = 75
Frequency/percent of BSW students who value gerontology = 80(.64)
Frequency/percent of MSW students who value gerontology = 25(.33)

Question 30

Which statistical test of significance would be appropriate for hypothesis testing with the social work student data presented above?

Question 31

The following table reports the results of an independent samples t-test comparing consumer satisfaction between clients participating in a telephone interview and clients participating in an in-person interview. What do you surmise regarding differences in satisfaction between these two groups; is there a statistically significant difference?

Question 32

Briefly explain what is meant by statistical power.