Question 1

A baseline, treatment, baseline single-subject design would be represented as:

Accepted Answer

The acronym for a baseline, treatment, baseline design is ABA, where A represents the baseline phase, and B represents the treatment phase. Therefore, the correct choice is B, as it represents the proper sequence of baseline, treatment, and baseline phases.

Question 2

Exhibit 11-5: Indicate whether the following statements refer to internal validity or external validity.
-Refer to Exhibit 11-5.Does this experiment represent reality?

Accepted Answer

The question refers to whether the experiment can be generalized to the real world, which is a measure of external validity. Internal validity refers to whether the experiment is accurately measuring the relationship between the variables being studied within the confines of the experiment.

Question 3

Experimental designs differ mainly in

Accepted Answer

Experimental designs can vary in the number of independent variables used and the method of assigning subjects to different treatments. The number of pre-measurements of the dependent variable is not a primary factor that determines the type of experimental design. Therefore, options A, B, and C are all partially correct but incomplete on their own. Only option D correctly and comprehensively describes the main differences between different experimental designs.

Question 4

Single-subject research would be described as

Accepted Answer

Single-subject research is considered quasi-experimental because it does not randomly assign participants to groups and often does not have a control group, which are characteristics of true experimental designs.

Question 5

The following experimental design would be recommended when 
(R) $\quad$ X $\quad$ Y
(R) $\quad$ --- $\quad$ Y

Accepted Answer

The given experimental design is suitable when a pretest may have an influence on the experimental treatment. In this design, one group (R) is given pretest and subjected to experimental treatment, and the other group (---) is not given a pretest but treated experimentally. This design helps in controlling the effect of pretest on the experiment. However, it does not address other issues like matching, control group, or pre-existing groups as specified in options A, B, and C, respectively.

Question 6

The major means of control in single-subject experimental designs is

Accepted Answer

The major means of control in single-subject experimental designs is replication. Replication involves repeating the same procedure or intervention multiple times in order to evaluate its consistency and effectiveness across different trials. This allows researchers to identify patterns of behavior and isolate the effects of the independent variable on the dependent variable. Randomization and statistical control are also important aspects of experimental design, but they are not typically the primary means of control in single-subject designs.

Question 7

The relationship between internal and external validity in research can best be described as

Accepted Answer

Internal validity refers to the extent to which a study measures what it intends to measure, while external validity refers to the generalizability of study findings to other populations or settings. If a study lacks internal validity, it means that there are flaws in the study design or methods that make it difficult to draw accurate conclusions about cause and effect relationships. This would also compromise the study's external validity, as it would be difficult to apply the findings to other contexts or populations. However, a study with strong internal validity may still have limited external validity if the sample or setting chosen is not representative of other populations or settings in which the findings might be applied.

Question 8

If a researcher compared left-handed versus right-handed girls on a reading test after giving half of them special training, then the attribute variable and one likely extraneous variable, would be respectively

Accepted Answer

The attribute variable is handedness (left-handed vs. right-handed), and a likely extraneous variable could be the age of the student, as it might affect reading test performance.

Question 9

A researcher used a pretest-posttest, control group quasi-experimental design.The experimental group had a mean achievement test score of 40 on the pretest and 70 on the posttest.The control group had a mean achievement score of 50 on the pretest and 60 on the posttest.What statistical technique should the researcher use to analyze these data?

Accepted Answer

ANCOVA (analysis of covariance) should be used because it can control for the pretest scores, which were different between the experimental and control groups. This will allow for a more accurate comparison of the posttest scores between the groups. A t-test or ANOVA would not control for pretest scores, and a chi-square would not be relevant for this type of data.

Question 10

Exhibit 11-5: Indicate whether the following statements refer to internal validity or external validity.
-Refer to Exhibit 11-5.Are the findings of this study a result of the experimental treatment?

Accepted Answer

The question is asking about whether the findings of the study are a result of the experimental treatment, which is a question of internal validity. External validity refers to the generalizability of the findings to the larger population.

Question 11

Which of the following types of experimental designs would be strongest for establishing cause and effect?

Accepted Answer

The randomized posttest control group design is the strongest for establishing cause and effect because it randomly assigns participants to either an experimental group or control group, and then measures the outcome (posttest) after the manipulation has occurred. This allows for comparison between the two groups and eliminates potential confounding variables.

Question 12

A researcher has developed a series of in-service training programs for teachers that he believes will improve their effectiveness in the classroom.The researcher observes and compares teacher classroom behavior before and after the teachers attend the in-service training.If this design has a flaw, suggest a way(s) that you would improve it.

Accepted Answer

Both options (a and b) are improvements to the design of the study. By using trained observers other than the researcher or videotapes with blind observers, the potential for bias is reduced. If the researcher is personally invested in the success of the program, their observations may be influenced by their desire for positive results. Using independent observers or blind evaluation helps to eliminate this potential bias.

Question 13

Multiple baseline designs may use more than one

Accepted Answer

Multiple baseline designs can use more than one subject, target behavior, setting, or AB unit. In fact, the whole purpose of multiple baseline designs is to establish a relationship between several variables, so multiple variations are utilized.

Question 14

Exhibit 11-5: Indicate whether the following statements refer to internal validity or external validity.
-Refer to Exhibit 11-5.Can the results of the study be applied to elementary school students in rural settings?

Accepted Answer

This statement refers to external validity, which concerns the generalizability of study findings to other populations or settings beyond the specific sample and context of the study. Internal validity, on the other hand, pertains to the soundness of the study design and methods for establishing cause-and-effect relationships between variables within the sample and context of the study.

Question 15

A basic characteristic of single-subject experimental research is

Accepted Answer

Single-subject experimental research typically involves repeated measures of the dependent variable in order to establish a baseline and assess the effects of manipulating the independent variable. Therefore, choice C is the most accurate characteristic of this type of research. Choices A and B are not true, as both the independent and dependent variables are typically measured repeatedly. Choice D is incorrect, as there is a clear and established set of characteristics that define single-subject experimental research.

Question 16

Exhibit 11-4.Identify the major threat to internal validity in the following research studies.
-Refer to Exhibit 11-4.Students who had low scores on a reading pretest were chosen for a special instructional program.This group showed significant gains on a reading achievement test administered after a period of four months.

Accepted Answer

Regression toward the mean is a major threat in this scenario because students with initially low scores are likely to show improvement over time simply due to statistical reasons, rather than the effect of the special instructional program.

Question 17

In the fall semester, a professor compared a lecture approach to teaching statistics (using a sophomore class) with a problem-oriented approach (using a senior class).Both sections were given the same final exam.The professor repeated the same experiment in the spring semester.This study shows a confounding of

Accepted Answer

The study compares two teaching approaches, lecture and problem-oriented, with two different class levels, sophomore and senior. Therefore, the study shows a confounding of teaching approaches with class level, as it is not clear whether the difference in test scores is due to the teaching approach or the class level.

Question 18

A basic assumption of the multiple baseline design is that the

Accepted Answer

The multiple baseline design assumes that the behaviors being targeted for treatment are independent of each other (c) and that the treatment will have specific effects on different behaviors (a). This design involves manipulating the treatment across multiple behaviors or participants at different points in time, allowing for comparisons between baseline and treatment phases. The assumption of independence between behaviors is necessary so that any observed changes in behavior can be attributed to the treatment and not to other extraneous factors that may affect all behaviors in the same way (such as history or maturation).

Question 19

Exhibit 11-4.Identify the major threat to internal validity in the following research studies.
-Refer to Exhibit 11-4.A researcher conducted a semester-long experiment comparing two instructional programs in math.During the administration of tests during the semester, the researcher found that about ten percent of the experimental group and about five percent of the control group were absent for each administration.

Accepted Answer

The major threat to internal validity in this study is mortality, as there was differential attrition (absenteeism) in the experimental and control groups. This could potentially affect the results by introducing a bias towards the group with more participants remaining in the study, and therefore invalidate the conclusions drawn from the study.

Question 20

An elementary teacher had a student, Andy, who showed signs of hyperactivity in the classroom.The teacher wanted to "experiment" to find ways to reduce the hyperactivity and bring about behavior more conducive to learning.She began to record the number of incidences of hyperactive behavior.After a period of time, she started to praise Andy and gave him tokens when he stayed in his seat and showed other less hyperactive behavior.The praise and tokens continued during which time the teacher observed and recorded Andy's behavior.The teacher then stopped the praise and the tokens and took measures of Andy's behavior.What data would the teacher look for to determine the effectiveness of her "treatment"?

Accepted Answer

The teacher's goal was to reduce hyperactivity, so a decrease in hyperactivity during the treatment phase would indicate that her approach was effective. The other options would suggest that the treatment either had no effect or made the hyperactivity worse.

Quiz 11: Experimental Research Design

A baseline, treatment, baseline single-subject design would be represented as:

Exhibit 11-5: Indicate whether the following statements refer to internal validity or external validity. -Refer to Exhibit 11-5.Does this experiment represent reality?

Experimental designs differ mainly in

Single-subject research would be described as

The following experimental design would be recommended when (R) \quad X \quad Y (R) \quad --- \quad Y