Comparison of Internal Validity Across Research Designs
Experimental, quasi-experimental, and non-experimental (correlational) research vary systematically along a spectrum of internal validity. True experimental research generally possesses the highest internal validity because it utilizes the manipulation of an independent variable and strict control over extraneous variables to confidently rule out alternative explanations. In contrast, non-experimental research ranks lowest in internal validity because it fundamentally lacks variable manipulation and control. Quasi-experimental research occupies the middle ground; it incorporates some structural features of an experiment but lacks others, such as the random assignment of participants.
0
1
Tags
KPU
Research Methods in Psychology - 4th American Edition @ KPU
Related
Double-Blind Procedure
Extraneous Variable
Placebo Effect
Prioritizing Validities
Comparison of Internal Validity Across Research Designs
According to the provided text, what does internal validity indicate in an empirical study?
True or False: According to the text, a statistical relationship between regular exercise and happiness confirms that exercise causes happiness.
Match each research scenario or design category with the description of its setup and corresponding effect on internal validity.
Types of Experimental Research
Basic Experimental Design Components
Interpreting Experimental Findings in Psychology
Reporting Research in Psychology
Weakness of Experimental Research: Artificial Settings
Ethical Constraints in Experimental Research
The Core Aim of Experimental Research
Primary Strength of Experimental Research: Establishing Causality
A researcher wants to test if a new note-taking strategy improves exam performance. They teach the new strategy to their morning class and the traditional strategy to their afternoon class. At the end of the unit, the morning class scores significantly higher on the exam. The researcher concludes that the new strategy causes better exam performance. Which of the following statements best analyzes the validity of this conclusion?
Falsifiability
Example of an Experiment: Lighting and Worker Productivity
Field Experiment
Experiment
Inability to Manipulate Variables
Experimental Record Keeping
Non-Experimental Research
Quasi-Experimental Research
Comparison of Internal Validity Across Research Designs
Applications of Surveys
Laboratory Experiment
Single-Subject Research
Match each component of experimental research with its specific role or function in the study design.
A researcher wants to know whether a new memorization strategy causes higher quiz scores. She recruits 50 participants and allows each person to choose whether to use the new strategy or their usual approach. She then compares the average quiz scores of the two groups. This study qualifies as an experiment because it compares two groups on a measured outcome.
In experimental research, what is the primary objective of systematically manipulating an independent variable and randomly assigning participants to conditions?
Match each core component of experimental research with its specific role in the research process.
A researcher investigating the effect of exercise on mood assigns 50 participants to a high-intensity workout group and 50 participants to a stretching group by flipping a coin for each person. True or False: Because the researcher used randomized assignment and systematically manipulated the type of exercise, this study qualifies as experimental research.
To establish a causal relationship between two variables, a researcher must strictly adhere to the logic of experimental design. Arrange the following steps in the sequence required to ensure internal validity and support a causal inference.
In the context of experimental research, which of the following best describes the fundamental goal of exercising a high degree of 'control' over variables of interest?
A researcher claims their study demonstrates that one variable directly produces a change in another, but a reviewer notices that participants were not randomly assigned to conditions. In evaluating the research design, the reviewer concludes that the lack of randomization prevents the study from supporting a(n) _____ inference.
In experimental research, the variable that the researcher systematically manipulates to observe its effects on the dependent variable is called the _____ variable.
An investigator wants to design a study to test a causal hypothesis. Evaluate the logical flow of components in experimental research by ordering these steps from the initial establishment of control to the final research objective.
Example of a Quasi-Experimental Study: Sex and Spatial Memory
One-Group Posttest Only Design
One-Group Pretest-Posttest Design
Nonequivalent Groups Design
Example of a Quasi-Experimental Study: Anti-Bullying Program
Selection Effect
Comparison of Internal Validity Across Research Designs
Tuskegee Syphilis Study
Elimination of Directionality Problem in Quasi-Experiments
Applications of Quasi-Experimental Research
Causal Limitations of Quasi-Experimental Research
Which of the following is a key characteristic that distinguishes quasi-experimental research from a true experiment?
Match each feature of a quasi-experimental design with the specific role it plays or the consequence it has on the quality of a psychological research study.
A clinical psychologist evaluates the effectiveness of a new mindfulness-based therapy by providing the treatment to all patients at one clinic while patients at a neighboring clinic receive standard care. Because the researcher is manipulating the treatment but is using pre-existing groups rather than assigning individual patients to conditions by chance, this study is best categorized as a(n) _________ research design.
A psychologist is testing the impact of a new peer-mentoring program in a local high school. Arrange the logical sequence of steps the psychologist would take to conduct a study that follows a quasi-experimental design and evaluates the strength of its causal claims.
A researcher claims that their quasi-experimental study provides the same level of confidence in causal conclusions as a true experiment because both designs involve the manipulation of an independent variable. This evaluative claim is scientifically sound.
Although quasi-experimental research offers more control than purely correlational studies, it generally possesses lower internal validity than a true experiment because it lacks random assignment or counterbalancing.
A researcher evaluates a new educational software by implementing it in one classroom and comparing the results to another classroom that continues with the standard curriculum. Which statement best explains why this quasi-experimental design has lower internal validity than a true experiment, yet still provides more control than a purely correlational study?
A psychology instructor asks students to match scenarios with their corresponding design feature. Match each research description to the quasi-experimental design feature or consequence it applies.
An investigator is analyzing the methodological differences between two research proposals. Study A uses random assignment and counterbalancing, whereas Study B implements a comparison condition using pre-existing groups without random assignment. In analyzing their quality, the investigator concludes that Study B generally possesses lower _____ than Study A.
Evaluate the following research design scenarios based on the standard of internal validity and control established in methodology. Arrange them in order from the design that provides the HIGHEST level of internal validity to the design that provides the LOWEST level of internal validity.
Conditions for Non-Experimental Research
Correlational Research
Longitudinal Research
Cross-Sectional Research
Example of Non-Experimental Research: Traffic Fatalities
Example of Non-Experimental Research: Intersection Observation
Complementary Use of Experimental and Non-Experimental Research
Observational Research
Quasi-Experimental Research
Comparison of Internal Validity Across Research Designs
Applications of Surveys
What is the defining characteristic of non-experimental research?
A study that measures the naturally occurring levels of social media use and self-esteem in a group of high school students to see how they are related is an example of non-experimental research.
Match the core characteristics of non-experimental research with the descriptions that best explain their role in a psychological study.
A researcher conducts a study on the relationship between students' natural sleep patterns and their academic performance by tracking them for a semester. Arrange the following steps in the logical order required to analyze this methodology and determine its scientific boundaries.
A researcher is tasked with designing a study to investigate how the frequency of naturally occurring social interactions in the workplace relates to the overall job satisfaction of employees. Since the researcher cannot ethically or practically assign employees to have more or fewer friends at work, which of the following research plans best constructs a valid non-experimental design for this investigation?
A psychologist is evaluating the most ethical way to study how surviving a natural disaster affects long-term personality. Because the researcher cannot ethically expose participants to such trauma, they must conclude that the most appropriate methodology is _____, even though this design cannot provide definitive evidence that the disaster caused the personality changes.
Non-experimental research methodologies are characterized by the lack of _____ of an independent variable.
Learn After
Overlap in Internal Validity Between Research Designs
Arrange the following research designs in order from LOWEST internal validity to HIGHEST internal validity.
A researcher wants to study whether a new therapy reduces anxiety. In Design A, participants are randomly assigned to either the therapy group or a no-therapy control group. In Design B, participants self-select into whichever group they prefer. Which design has higher internal validity, and what is the primary reason?
Based on the spectrum of internal validity, match each research scenario with the level of internal validity it typically provides.
True or False: According to the spectrum of internal validity, the structural feature that distinguishes a true experiment from a quasi-experiment—thereby placing it at the highest level of validity—is the manipulation of an independent variable.
In the comparison of internal validity across research designs, what is the primary structural reason that quasi-experimental research occupies the middle ground between experimental and non-experimental research?
Quasi-experimental research and non-experimental (correlational) research share the same level of internal validity because both lack the random assignment of participants.
A researcher evaluating the rigor of a causal claim finds that a study utilizes strict control over extraneous variables, the manipulation of an independent variable, and random assignment of participants. Consequently, the researcher would judge this design as possessing the _____ level of internal validity on the standard research spectrum.
Match each structural feature to the role it plays in determining where a research design falls on the internal validity spectrum.
A researcher compares a quasi-experimental study and a true experiment that both investigated the same causal relationship. The quasi-experimental study produced a weaker causal conclusion. Analyzing the structural source of this difference, the researcher determines that the quasi-experimental study lacked _____, which allowed pre-existing differences between groups to serve as alternative explanations for the observed outcomes.
A researcher wants to determine whether a new stress-management workshop causes a reduction in student anxiety. Evaluate each design approach below and arrange them in order from the approach that LEAST effectively supports a causal conclusion (order 1) to the approach that MOST effectively supports a causal conclusion (order 3), justifying your ranking based on the internal validity each design provides.