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

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.

Define experimental research based on its core components. In your definition, list the key practices involved in control, assignment, and manipulation within this method, and state the primary objective of using this approach.

Explain how this study meets the definition of experimental research. Specifically, identify how the variables are handled (manipulated and measured), how participants are distributed, and what kind of conclusion the psychologist is equipped to draw based on this design.

Imagine you want to test the hypothesis that a new online tutoring platform improves math quiz scores in high school students. Apply the principles of experimental research to explain in 1-3 sentences how you would implement randomized assignment and systematic manipulation in this study.

Experiment (Psychological Research)

A psychologist designs a study to test whether listening to classical music while studying improves test performance. She recruits 80 undergraduate students, uses a random number generator to assign 40 students to study with classical music and 40 to study in silence, and administers the same 20-item algebra test to both groups in the same laboratory room under identical lighting and temperature.

Match each element of this study to the experimental component it represents.

A researcher investigates a new cognitive training program by comparing a group of volunteers who chose to participate in the program against a group of volunteers who chose not to. By conducting all sessions in the exact same laboratory room, under identical environmental conditions, and using identical testing materials, the researcher has established sufficient experimental control to confidently draw a causal inference that the training program caused any observed differences in cognitive performance.

Falsifiability

Limitations of the Scientific Method

Non-Empirical Questions

Example of an Empirical Question

Conceptualizing Single Variable Research Questions

Evaluating Research Questions

Empirical Evidence

Which of the following best describes the defining characteristic of an empirical question?

A question about whether it is 'right' or 'wrong' to use animals in research is considered an empirical question because researchers can measure the animals' physiological stress levels.

Match each psychological research inquiry with the classification that best explains why it is, or is not, considered an empirical question.

A researcher is evaluating the inquiry: 'Does frequent social media use lead to lower self-esteem?' To confirm this is a valid empirical question, arrange the following steps in the logical sequence required to analyze the inquiry's structure.

A cognitive psychologist wants to transform the vague interest 'Does sleep affect the mind?' into a specific, testable empirical question. Arrange the following components in the logical order required to synthesize a complete inquiry that can be resolved through systematic, observable evidence.

The scope of the scientific method is strictly restricted to answering empirical questions because science relies on systematic, observable evidence.

A psychologist is designing a new research study. Which of the following best explains why the question 'Does practicing mindfulness meditation increase empathy in college students?' is classified as an empirical question, whereas the question 'Should college students be required to practice mindfulness meditation?' is not?

A researcher evaluates the inquiry 'Is it more ethical to use human or animal subjects?' and determines that it is not an empirical question. This judgment is correct because the 'ethicality' of a choice is a value-based decision that cannot be resolved through _____ evidence alone.

A research methods instructor presents four inquiries and asks students to identify the specific feature that determines whether each can be addressed using the scientific method. Match each inquiry to the feature that best explains its empirical or non-empirical status.

A student defends their proposed research question 'Are individuals who exercise regularly more likely to report lower stress levels than those who do not?' by arguing it qualifies as a valid empirical question suitable for scientific investigation. The student's justification is sound because this question asks about the way the world actually is and can be resolved by collecting and evaluating systematic, _____ evidence — the defining criterion that separates empirical questions from non-empirical ones such as value or aesthetic judgments.

Define what an empirical question is and explain why the scope of the scientific method is strictly restricted to addressing only these types of questions.

Based on the features of science and the definition of an empirical question, diagnose why the student's current question is not empirically testable, and explain how the student should modify their research focus to make it suitable for scientific inquiry.

A clinical psychologist wants to investigate mindfulness but starts with the question: 'Is mindfulness meditation a morally superior way to live compared to other lifestyles?' Apply the criteria for generating a valid empirical question to rewrite this inquiry so that it can be addressed using the scientific method.