Exam 2 - Section 6

Question 1

What are the two critical elements of a true experimental research design?

Answer 1

(1) Manipulation or Control of the Independent Variables and (2) Randomization of participants to assure group “equivalency”

Question 2

What are the main features or differences of Group Studies?

Answer 2

Reports made on the group performance, instead of individual scores; minimum number of participants per group; comparison of means and SD since the focus is on group data

Question 3

What does the notation “R” stand for?

Answer 3

Random Assignment

Question 4

What does the notation “X” stand for?

Answer 4

Experimental treatment/condition

Question 5

What does the notation “O” stand for?

Answer 5

Observations or measurement

Question 6

What are the key features of a Posttest-Only Design?

Answer 6

Randomization of participants to the control; manipulation of the independent variable; measurement/observation taken only after the treatment

Question 7

What are the key features/elements of a Pretest-Posttest Randomized Control Group Design?

Answer 7

Randomization of participants; Pretest or baseline measurement; Manipulation of the independent variable; Posttest measurement after the treatment

Question 8

What is one benefit of a Pretest-Posttest Randomized Control Group Design?

Answer 8

Assures the groups are similar before intervention (equivalency of groups)

Question 9

What are the key features of the Solomon Randomized Four-Group Design?

Answer 9

Random of assignment of participants across all four groups; two groups have the pretest and two do not; two groups receive treatment or intervention and two do not

Question 10

What is one benefit of the Solomon Randomized Four-Group Design?

Answer 10

Verifies that learning did not occur because of the pretest

Question 11

What are the key elements of a Factorial Design?

Answer 11

Manipulation of two or more independent variables at the same time in the same study

Question 12

What does a Factorial Design allow investigators to examine?

Answer 12

How each variable affects the outcome; how independent variables work together or influence one another (interaction effects); look at each factor independent from one another and see if the factors are contingent or interact with one another

Question 13

What is a Main Effect in terms of a Factorial Design?

Answer 13

The effect associated with each independent variable; a significant Main Effect means there is a difference between the levels of one of the independent variables

Question 14

What is an Interaction Effect in terms of a Factorial Design?

Answer 14

The independent variables work together or influence one another

Question 14

What is Internal Validity?

Answer 14

The extent in which researchers’ conclusions about cause/effect relationships are accurate

Question 15

What Aspects can Impact/Threaten Experimental Control (Important for Internal Validity)?

Answer 15

History, Instrumentation, Maturation, Selection, Mortality, and Statistical Regression

Question 16

What is History in terms of Experimental Control Threats?

Answer 16

“Outside” influences that occurred during the course of a study; can influence the observed outcomes at the end of a study; Example: participants are distracted by news of a new strain of COVID-19, so they cannot focus on the study

Question 17

What is Instrumentation in terms of Experiment Control Threats?

Answer 17

Changes in equipment or human observers; Example: during the pretest, you took measures for 15 minutes, but during the posttest you took measures for 30 minutes

Question 18

What is Maturation in terms of Experimental Control Threats?

Answer 18

Performance influence by participants’ development or recovery; Example: you are conducting a study on stroke patients, but over time they begin to naturally recover from the stroke

Question 19

What is Selection in terms of Experimental Control Threats?

Answer 19

Groups vary in some way; participants/groups differ in a systematic way, rather than in a random way, prior to a study; Example: those with a lower IQ score were placed in Group A, and those with a higher IQ score were placed in Group B

Question 20

What is Mortality in terms of Experimental Control Threats?

Answer 20

Participants discontinue participation and loss may not be “random”; participants drop out before the end of a study; Example: participants with the lowest scores or those making less progress in treatment drop out of the study

Question 21

What is Statistical Regression in terms of Experimental Control Threats?

Answer 21

Effect of repeated testing may cause change in some scores; effect of being tested repeatedly; Example: if a participant scores extremely high on a test, there’s a strong probability that the condition had nothing to do with it, and the next test taken will be closer to the mean/average score