Question 1

In the analysis of single-case data, it has been found that

Accepted Answer

Serial dependency refers to the idea that observations in a time series (like those in single-case designs) can be correlated with preceding observations, which can complicate the analysis and interpretation of the data. This is a recognized issue in the analysis of single-case data, where the independence of observations, a key assumption in many statistical analyses, is violated.

Question 2

The A-B-A-B design

Accepted Answer

The answer of The A-B-A-B design
...

Question 3

The major threat to the external validity of single-case experiments is

Accepted Answer

The major threat to the external validity of single-case experiments is the use of one or a few cases as a basis for generalizing to a larger population. This limited sample size makes it difficult to ensure that findings are applicable beyond the specific cases studied.

Question 4

If the range of difficulty of test items is limited, the test may be subject to

Accepted Answer

A ceiling effect occurs when the range of difficulty of test items is limited, making it difficult for the test to distinguish between high performers because they all score near the top.

Question 5

An appropriate technique for determining the statistical significance of pretest-posttest change in experiments is

Accepted Answer

Analysis of variance for repeated measures is an appropriate technique for determining the statistical significance of pretest-posttest change in experiments because it takes into account the correlation between the pretest and posttest scores.

Question 6

The validity of gain scores based on repeated administration of the same test to research participants

Accepted Answer

The validity of gain scores, which are differences in test scores from one time to another, depends on the assumption that the test has equal intervals across all of its measurement points. This ensures that a given difference in scores represents the same amount of change in the measured construct, regardless of where on the scale that change occurs.

Question 7

In an experiment that includes a pretest and posttest, describe a statistical technique that can be used to reduce initial group differences resulting from nonrandom assignment of research participants to the experimental and control treatments. Indicate the function of the pretest and posttest in thestatistical technique.

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The answer of In an experiment that includes a pretest...

Question 8

a. What is the main difference between a static-group comparison design and a nonequivalent controlgroup design?
b. Which design is stronger in internal validity, and why?

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The answer of a. What is the main difference between...

Question 9

a. What threat to external validity is controlled by the Solomon four-group design?
b. How is the threat to external validity controlled by this design?

Accepted Answer

The answer of a. What threat to external validity is...

Question 10

Five types of independent variables can be employed in an experiment. Name and describe three of these types of independent variables.

Accepted Answer

The answer of Five types of independent variables can be...

Question 11

a. What is the purpose of aptitude-treatment interaction (ATI) research?
b. What type of experimental design is employed in ATI research?

Accepted Answer

The answer of a. What is the purpose of aptitude-treatment...

Question 12

Using a factorial design, a researcher conducted an experiment to determine how prior vocabulary knowledge and a new reading program influence students' reading comprehension. The new reading program is the experimental treatment, and the existing reading program is the control treatment.
a. Identify what would be a main effect in this experiment, and define what is meant by a main effect.
b. Identify what would be an interaction effect in this experiment, and define what is meant by an interaction effect.

Accepted Answer

The answer of Using a factorial design, a researcher conducted...

Question 13

Why is the A-B-A-B design considered more acceptable from an ethical standpoint than the A-B-A design?

Accepted Answer

The answer of Why is the A-B-A-B design considered more...

Question 14

What is the main difference between an A-B-A design and a multiple-baseline design in a single-case experiment?

Accepted Answer

The answer of What is the main difference between an...

Question 15

Which of the two single-case designs, A-B or A-B-A, has superior internal validity? Why?

Accepted Answer

The answer of Which of the two single-case designs, A-B...

Question 16

Describe two potential problems that can occur when raw gain scores (posttest scores minus pretest scores) are used to measure the amount of learning that individuals achieve as the result of an experimental intervention.

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The answer of Describe two potential problems that can occur...

Question 17

Describe two alternatives to the use of gain scores to analyze research data from a correlational or experimental study that included administration of a pretest and a posttest.

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The answer of Describe two alternatives to the use of...

Question 18

A research team conducted an experiment in which they administered a mathematics test before and after students had participated in a new individualized curriculum. Parallel forms of the test were used as the pretest and posttest, and the range of possible scores was 0-100 on each. In analyzing data from the experiment, the researcher found that students in the lowest quartile on the pretest (M = 15.5) made a good gain (posttest M = 37.6), whereas students in the highest quartile on the pretest (M = 83.7) declined slightly (posttest M = 80.1). From these differences in gain scores, they concluded that the new curriculum is more effective for students of low ability than for students of high ability. What are two other interpretations that can be made of the differences in gain scores?

Accepted Answer

The answer of A research team conducted an experiment in...

Question 19

A research team wishes to determine which of two types of staff development is more effective. The administrators of a school district agree to the experiment, and all the teachers in two high schools agree to participate and to take the pretest and posttest. However, the administrators insist that the teachers cannot be randomly assigned to the staff development programs. All teachers in one high school must participate in program A, and all teachers in the other high school must participate in program B.
a. If the researchers agrees to this condition, what type of experimental design must she use and why?
b. What is the main threat to internal validity in this type of experimental design, and how can it be handled?

Accepted Answer

The answer of A research team wishes to determine which...

Question 20

A researcher plans to test the effectiveness of self-paced instruction vs. conventional instruction for male and female students of varying levels of ability. There are a total of 150 students: 60 boys and 90 girls. Within each of these groups (boys and girls), there are an equal number of high-, middle-, and low-ability students. Make a chart that illustrates the experimental design for this research project, and show the number of students in each experimental group. Also, list each interaction effect that can be analyzed.

Accepted Answer

The answer of A researcher plans to test the effectiveness...

Quiz 13: Experimental Research: Designs, Part 2