Research Designs in Psychology

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Questions and Answers

What type of research design is used when the same participants complete cognitive tests after different sleep conditions?

Between-subjects design

Cross-sectional design

Within-subjects design (correct)

Longitudinal design

In a within-subjects design, how many conditions does each participant experience?

Only one condition

Two or more conditions (correct)

Only the control condition

None of the above

What is a major disadvantage of between-subjects designs?

It eliminates the need for a control group

It often requires a longer testing time

It typically requires fewer participants

It can introduce more individual differences as confounding variables (correct)

Which design is more likely to detect a treatment effect if it exists?

Within-subjects design Signup and view all the answers

What is the primary role of the dependent variable in a study?

To observe and measure behavior or response Signup and view all the answers

When is it preferable to use a between-subjects design?

When there are expected large individual differences Signup and view all the answers

Which statement best describes an experimental condition?

It is the group that receives the experimental treatment. Signup and view all the answers

What is one advantage of using a within-subjects design?

It typically requires fewer participants Signup and view all the answers

In the example regarding room temperature and students' performance, what designation is given to the room temperature?

Independent variable Signup and view all the answers

In an experiment comparing two exercise programs, what type of design is being used if different groups follow each program?

Between-subjects design Signup and view all the answers

What are extraneous variables?

Any variables not controlled that could affect the dependent variable Signup and view all the answers

What effect can time-related factors have in a within-subjects design?

They can distort the results Signup and view all the answers

Which of the following best describes a control condition in an experiment?

It is where the treatment is not administered. Signup and view all the answers

What describes confounding variables in an experiment?

Variables that can systematically change alongside the independent and dependent variables Signup and view all the answers

What was the independent variable in the study by Ford and Torok (2008)?

Effectiveness of motivational signs Signup and view all the answers

What was concluded about participants who shouted swear words in the study conducted by Stephens, Atkins, and Kingston (2009)?

They endured less pain than those who shouted neutral words. Signup and view all the answers

What characterizes a nonexperimental design compared to experimental designs?

It makes no attempt to minimize threats to validity. Signup and view all the answers

Which scenario best exemplifies a nonexperimental study?

Measuring the impact of school policy on student performance. Signup and view all the answers

In a nonequivalent group design, how are the groups formed?

Under circumstances that do not allow for random assignment. Signup and view all the answers

What issue arises from individual differences in nonequivalent group designs?

They can introduce a confound in the findings. Signup and view all the answers

Which statement correctly describes a between-subjects design?

Different groups of participants are compared under equivalent circumstances. Signup and view all the answers

Which of the following indicates a characteristic of within-subjects designs?

Participants have their scores compared against their own previous scores. Signup and view all the answers

What is one primary goal when conducting a nonequivalent group design study?

To demonstrate that a differentiating factor causes differences in outcomes. Signup and view all the answers

Which of these designs implies some level of variable manipulation?

Pre–post design. Signup and view all the answers

What is the primary purpose of the static group comparison design?

To show that a treatment has an effect by comparing with a treated group. Signup and view all the answers

In the pretest–posttest nonequivalent control group design, what do both groups have in common during the study?

They are measured over the same time period. Signup and view all the answers

Which of the following describes a key characteristic of a quasi-experimental design?

It compares groups that are not equivalent. Signup and view all the answers

What conclusion can a researcher draw if both groups in a pretest–posttest study show similar changes?

Time-related factors are likely responsible for the change. Signup and view all the answers

What is one of the main limitations the pretest–posttest nonequivalent control group design tries to address?

Differences between treatment and control groups. Signup and view all the answers

What is the significance of the control group in a quasi-experimental design?

It provides a benchmark against which to compare the treated group. Signup and view all the answers

Which factor does the pretest–posttest nonequivalent control group design minimize?

The impact of time-related variables. Signup and view all the answers

How do researchers demonstrate the effectiveness of treatment in a static group comparison study?

By comparing posttest scores between treated and control groups. Signup and view all the answers

What is the main purpose of a pre–post design?

To evaluate the influence of an intervening treatment over time Signup and view all the answers

Which research design lacks a control group?

Pre–post design Signup and view all the answers

In what research design is a series of observations made before and after a treatment or event for each participant?

Time-series design Signup and view all the answers

A researcher is observing the same group of participants before and after an intervention. What type of research design is being used?

Within-subjects experiment Signup and view all the answers

What distinguishes a pretest–posttest nonequivalent control group design from a pre–post design?

It has a control group for comparison. Signup and view all the answers

Which statement best characterizes a between-subjects experimental design?

Each participant is assigned to one condition of the experiment. Signup and view all the answers

What is a primary disadvantage of a between-subjects design?

Individual differences between participants can affect results. Signup and view all the answers

Which of the following accurately describes the scores in a between-subjects experiment?

Only one score is obtained for each participant. Signup and view all the answers

In a within-subjects experimental design, what is being compared?

The same group of participants across multiple conditions. Signup and view all the answers

What must a within-subjects design satisfy to qualify as an experiment?

There must be manipulation of an independent variable. Signup and view all the answers

Which statement defines a key characteristic of a within-subjects design?

The same individuals are engaged in all treatment conditions being compared. Signup and view all the answers

What is a potential outcome of using a between-subjects design?

It complicates the analysis due to unique participant scores. Signup and view all the answers

How does a within-subjects design seek to find differences in treatment conditions?

By observing changes in the same set of individuals across conditions. Signup and view all the answers

Study Notes

Research Process: Selecting a Research Strategy and Experimental Research Design

Research process steps include:
- Research idea
- Convert research idea into research hypothesis
- Constructs and operational definitions
- Identifying participants (sampling)
- Selecting a research strategy
- Selecting a research design
- Conduct the study
- Evaluate the data
- Report the results
- Refine research idea

Research Strategy

Definition: A broad approach to research, determined by the question the study aims to answer.
Types of research strategies:
- Experimental research strategy
- Quasi-experimental research strategy
- Non-experimental research strategy
- Correlational research strategy
- Descriptive research strategy

Experimental Research Strategy

Definition: Establishes cause-and-effect relationships between variables.
Key elements of an experiment:
- Manipulation: Changing the value of one variable (independent) to create treatment conditions.
- Measurement: Measuring a second variable (dependent) within each treatment condition.
- Comparison: Comparing scores in different treatment conditions to determine impact of manipulation.
- Control: Controlling all other variables to isolate the effect of the independent variable on the dependent variable.

Four Basic Elements of Experiment

Manipulation: One variable is changed to form treatment conditions. This enables researchers to understand relationship direction (Ice cream sales rise and fall with temperature.).
Measurement: A second variable is measured to obtain scores for each treatment condition.
Comparison: Scores are from one treatment condition compared to the other. Consistent variance signals manipulation causes change.
Control: Controlling other variables to ascertain that they don't affect the key variables studied. This ensures that change is genuinely related to manipulation, not other factors.

Types of Variables

Independent variable: The variable manipulated by the researcher (e.g., room temperature).
Dependent variable: The variable measured for changes. (e.g., student performance).
Extraneous/confounding variable (e.g., noise level, room illumination, humidity.) : Variables that can influence the dependent variable but are not of primary interest.

Experimental Conditions

Experimental condition: The group receiving the treatment.
Control condition: The group not receiving the treatment.

Research Design

Definition: A general plan for implementing a research strategy.
It covers:
- Whether the study involves groups or individual participants.
- How comparisons are made (within a group or between groups).
- Number of variables included.

Experimental Research Designs

Two main designs:
- Between-subjects design
- Within-subjects design

Between-Subjects Design

Definition: Different people test each condition to limit the exposure each person has to a single treatment.
Independent group of individuals for each treatment condition.
Results contain only one score per participant.
Emphasizes controlling external factors that could affect results.

Within-Subjects Design

Definition: Same group of people experience all conditions.
Participants serve as their own control
Eliminates variance due to participant differences.

Assumptions for Within-Subjects Design

Normality: Scores of dependent variable are normally distributed in each condition.
Sphericity: Variances of differences among conditions are equal.
Independence of Observations

Assumptions for Between-Subjects Design

Random Assignment: Participants randomly allocated to different groups.
Independence: Observations from one group are not influenced by another group.
Homogeneity of Variance: Variances in each group should be equal.
Normality: Distribution of the dependent variable should be approximately normal within each group.
Control of Extraneous Variables: Control extraneous variables to avoid impacting the result.

Nonexperimental and Quasi-experimental Research Strategies

Non-experimental strategies: comparing scores from different groups/ conditions using non-manipulated variables.
Quasi-experimental strategies: Attempt to control threats to internal validity.

Nonequivalent Groups Design

Used when random assignment is not possible
Compares preexisting groups
Includes differential research, posttest-only control, and pretest-posttest nonequivalent group designs.

Pre-Post Design

Observation made before and after treatment for one group.
Evaluates treatment/event impact by comparing pre- and post-observations.

Time-Series Design

A series of observations before and after treatment/event
Useful for evaluating the impact of interventions.

One-Group Pretest-Posttest Design

One group measured before and after treatment.
No comparison group, so cause-and-effect are less clear.

Equivalent Time-Samples Design

Measures treatment's effect by alternately administering and withdrawing the treatment.
Useful when treatment's impact is temporary.

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Description

This quiz explores various research designs used in psychology, focusing on within-subjects and between-subjects designs. Test your knowledge on dependent variables, control conditions, and the effects of sleep on cognitive tests. Perfect for psychology students looking to enhance their understanding of experimental methods.