Question 1

Which threat to the validity of an interrupted time-series design is controlled in the multiple time-series design?

Accepted Answer

A)  selection 
B)  history 
C)  instrumentation 
D)  testing 
A)  selection 
B)  history 
C)  instrumentation 
D)  testing

Question 2

Attrition effects pertain only to studies using the aged or disabled as experimental subjects.

Accepted Answer

A) True 
 B)False

Question 3

Which threat to internal validity is controlled in the one-group pretest-posttest design (O1 X O2)?

Accepted Answer

A)  attrition 
B)  testing 
C)  history 
D)  maturation 
A)  attrition 
B)  testing 
C)  history 
D)  maturation

Question 4

Suppose you have developed a treatment to help people stop smoking. To test the treatment, you identify smokers in a campus survey, and then you contact them to ask if they wish to volunteer for your smoking cessation treatment. Those who volunteer are given the treatment, and those who do not are assigned to the control group. After a month, a higher percentage of the treatment subjects than the controls has stopped smoking. Aside from the treatment, what may account for this difference?

Accepted Answer

A)  testing 
B)  testing-X interaction 
C)  instrumentation 
D)  selection 
E)  maturation 
A)  testing 
B)  testing-X interaction 
C)  instrumentation 
D)  selection 
E)  maturation

Question 5

In a study of interpersonal attraction, subjects watched a videotape featuring a person who was (1) either competent or incompetent, and (2) either did or did not spill coffee on himself (i.e., "blundered"). After watching the tape, all subjects indicated how much they liked the person in the film on a seven-point scale. Consider the following outcome:
  This outcome shows

Accepted Answer

A)  a main effect for competence only. 
B)  a main effect for blunder only. 
C)  main effects for both competence and blunder. 
D)  an interaction between competence and blunder. 
A)  a main effect for competence only. 
B)  a main effect for blunder only. 
C)  main effects for both competence and blunder. 
D)  an interaction between competence and blunder.

Question 6

Which of the following design features is present in a factorial design?

Accepted Answer

A)  the dependent variable is measured both before and after the manipulation 
B)  a pretest measure is used in each experimental condition 
C)  there is more than one measure of the dependent variable 
D)  more than one independent variable is manipulated 
A)  the dependent variable is measured both before and after the manipulation 
B)  a pretest measure is used in each experimental condition 
C)  there is more than one measure of the dependent variable 
D)  more than one independent variable is manipulated

Question 7

A posttest-only control group design eliminates the possible effects of testing and testing-X interaction.

Accepted Answer

A) True 
 B)False

Question 8

Selection effects may occur whenever college students are used as subjects.

Accepted Answer

A) True 
 B)False

Question 9

__________ is likely to be a threat to internal validity whenever subjects are assigned to experimental conditions on the basis of their low or high scores on the pretest.

Accepted Answer

A)  Testing 
B)  Differential attrition 
C)  Instrumentation 
D)  Statistical regression 
A)  Testing 
B)  Differential attrition 
C)  Instrumentation 
D)  Statistical regression

Question 10

3. A pharmaceutical company wants to market what seems to be a revolutionary new drug: a near-cure for the common cold. Researchers in the R & D division randomly select 1,000 persons from the city where the company is headquartered to participate in a test study. Each participant is observed for six months. For the first three months, baseline data are collected. For the last three months, the participants take a weekly dose of the common-cold cure. Sure enough, 15 percent of the participants contracted a cold during the first three months, whereas only 2 percent did so in the second three months.
a. Using the notation introduced in Chapter 8, carefully diagram the design of this study. Be sure to label or specify the meaning of each "letter" in the diagram.
b. Is this a true experiment? If so, describe the design features that make it a true experiment. If not, describe what feature(s) of a true experiment are missing.
c. What is the purpose of randomly selecting participants? Does this enhance the internal validity or external validity of the study? 
d. The investigators are confident that they have accurately recorded the incidence of colds and that the observed difference (15 percent versus 2 percent) is statistically significant. Therefore, they rush their findings to you, the company president, who must decide whether the data are convincing enough for the company to put the product on the market. Knowing about threats to internal validity, you consider the following: selection, statistical regression, history, instrumentation, and attrition. Which, if any, of these threats might undermine the validity of this study? Briefly explain.

Accepted Answer

a. The design of this study can be diagr

Question 11

Which of the following is not a potential threat to the validity of a within-subjects design?

Accepted Answer

A)  testing 
B)  testing-X interaction 
C)  order of the treatment and control conditions 
D)  selection 
A)  testing 
B)  testing-X interaction 
C)  order of the treatment and control conditions 
D)  selection

Question 12

In a within-subjects design, each subject participates in all experimental conditions.

Accepted Answer

A) True 
 B)False

Question 13

Which of the following statements is false about quasi-experimental designs?

Accepted Answer

A)  They use a variety of approaches to establish internal validity. 
B)  They are more effective than pre-experimental but less effective than true experimental designs in controlling for extraneous variables. 
C)  Their major deficiency is the absence of a pretest. 
D)  They lack one or more features of a true experiment. 
A)  They use a variety of approaches to establish internal validity. 
B)  They are more effective than pre-experimental but less effective than true experimental designs in controlling for extraneous variables. 
C)  Their major deficiency is the absence of a pretest. 
D)  They lack one or more features of a true experiment.

Question 14

Quasi-experimental designs generally are inferior to pre-experimental designs.

Accepted Answer

A) True 
 B)False

Question 15

An experiment's internal validity depends upon how well it controls for extraneous variables.

Accepted Answer

A) True 
 B)False

Question 16

Maturation effects may occur when experimental conditions are run at different times of the day.

Accepted Answer

A) True 
 B)False

Question 17

Which of the following would not be a potential threat to internal validity in the pretest-posttest design (O1 X O2)?

Accepted Answer

A)  testing 
B)  maturation 
C)  history 
D)  selection 
A)  testing 
B)  maturation 
C)  history 
D)  selection

Question 18

Random assignment controls for the effects of selection and statistical regression.

Accepted Answer

A) True 
 B)False

Question 19

A 2 × 3 factorial design has five experimental conditions.

Accepted Answer

A) True 
 B)False

Question 20

Which of the following experimental designs can provide information on interaction effects?

Accepted Answer

A)  pretest-posttest control group design 
B)  posttest-only control group design 
C)  static group comparison 
D)  factorial design 
A)  pretest-posttest control group design 
B)  posttest-only control group design 
C)  static group comparison 
D)  factorial design

Which threat to the validity of an interrupted time-series design is controlled in the multiple time-series design?

Attrition effects pertain only to studies using the aged or disabled as experimental subjects.

Which threat to internal validity is controlled in the one-group pretest-posttest design (O₁ X O₂)?

Which of the following design features is present in a factorial design?

A posttest-only control group design eliminates the possible effects of testing and testing-X interaction.

Selection effects may occur whenever college students are used as subjects.

__________ is likely to be a threat to internal validity whenever subjects are assigned to experimental conditions on the basis of their low or high scores on the pretest.

Which of the following is not a potential threat to the validity of a within-subjects design?

In a within-subjects design, each subject participates in all experimental conditions.

Which of the following statements is false about quasi-experimental designs?

Quasi-experimental designs generally are inferior to pre-experimental designs.

An experiment's internal validity depends upon how well it controls for extraneous variables.

Maturation effects may occur when experimental conditions are run at different times of the day.

Which of the following would not be a potential threat to internal validity in the pretest-posttest design (O₁ X O₂)?

Random assignment controls for the effects of selection and statistical regression.

A 2 × 3 factorial design has five experimental conditions.

Which of the following experimental designs can provide information on interaction effects?

Introduction

The Nature of Science

Research Ethics

Elements of Research Design

Measurement

Sampling

Experimentation

Survey Research

Survey Instrumentation

Field Research

Research Using Available Data

Multiple Methods

Data Processing and Elementary Data Analysis

Multivariate Analysis

Writing Research Reports

Filters

Exam 8: Experimental Designs

Which threat to the validity of an interrupted time-series design is controlled in the multiple time-series design?

Attrition effects pertain only to studies using the aged or disabled as experimental subjects.

Which threat to internal validity is controlled in the one-group pretest-posttest design (O1 X O2)?

Which of the following design features is present in a factorial design?

A posttest-only control group design eliminates the possible effects of testing and testing-X interaction.

Selection effects may occur whenever college students are used as subjects.

__________ is likely to be a threat to internal validity whenever subjects are assigned to experimental conditions on the basis of their low or high scores on the pretest.

Which of the following is not a potential threat to the validity of a within-subjects design?

In a within-subjects design, each subject participates in all experimental conditions.

Which of the following statements is false about quasi-experimental designs?

Quasi-experimental designs generally are inferior to pre-experimental designs.

An experiment's internal validity depends upon how well it controls for extraneous variables.

Maturation effects may occur when experimental conditions are run at different times of the day.

Which of the following would not be a potential threat to internal validity in the pretest-posttest design (O1 X O2)?

Random assignment controls for the effects of selection and statistical regression.

A 2 × 3 factorial design has five experimental conditions.

Which of the following experimental designs can provide information on interaction effects?

Introduction

The Nature of Science

Research Ethics

Elements of Research Design

Measurement

Sampling

Experimentation

Survey Research

Survey Instrumentation

Field Research

Research Using Available Data

Multiple Methods

Data Processing and Elementary Data Analysis

Multivariate Analysis

Writing Research Reports

Filters

Which threat to internal validity is controlled in the one-group pretest-posttest design (O₁ X O₂)?

Which of the following would not be a potential threat to internal validity in the pretest-posttest design (O₁ X O₂)?