Experimental research

Summary

In this educational video, Professor Doug Crawl from Northern Kentucky University explains the concept of experimental research in psychology. He illustrates how the study of variables can reveal causal relationships, using the example of whether violent media increases aggression. The video clarifies the roles of independent and dependent variables and addresses potential confounds in experimental design. It emphasizes the importance of random assignment to ensure that any observed effects can be attributed to the independent variable, thus establishing causality.

Takeaways

• 🧑‍🏫 Experimental research aims to determine if one variable causes another, which is crucial in psychology.
• 🔍 Examples of experimental research questions include whether certain therapies reduce depression or if specific techniques reduce violent crime.
• 🎬 A basic experimental study might involve showing participants either a violent film clip or a neutral one, like a documentary on penguins.
• 🔄 The independent variable is what the experimenter manipulates (e.g., type of film), while the dependent variable is what is measured (e.g., levels of aggression).
• ❓ The goal is to see if changes in the independent variable cause changes in the dependent variable.
• ⚠️ Confounds occur when there are multiple possible explanations for the findings, such as differences between participant groups.
• 🔀 Random assignment helps eliminate confounds by evenly distributing participant characteristics across experimental conditions.
• 📊 By ensuring groups are similar before the experiment, any differences found afterward can be attributed to the manipulation of the independent variable.
• ✅ Proper random assignment and control of variables allow researchers to determine causality in experimental research.
• 🎓 The example highlights the importance of controlling extraneous variables to make valid causal inferences in psychological studies.

Q & A

What is experimental research?

Experimental research seeks to discover if one variable causes another, often used in psychology to determine causal effects.

Can you provide an example of a question experimental research might seek to answer in psychology?

One example is determining whether a particular type of therapy reduces levels of depression.

What are independent and dependent variables in experimental research?

Independent variables are the ones that the experimenter controls or manipulates, while dependent variables are the ones being measured and are expected to change in response to the independent variable.

In the example of studying the effect of violent media on aggression, what are the independent and dependent variables?

The independent variable is the type of film watched (violent or neutral), and the dependent variable is the level of aggression observed in viewers.

What is a confound in experimental research?

A confound is a situation where there is more than one possible explanation for the findings, making it unclear what caused the observed effect.

How can confounds affect the validity of an experiment's results?

Confounds can lead to incorrect conclusions because they introduce alternative explanations for the observed effects, making it difficult to determine the true cause.

What strategy can be used to eliminate confounds in an experiment?

Random assignment can be used to mix up participants from different groups, ensuring that the groups are equal before the experiment begins and eliminating potential confounds.

Why is random assignment important in experimental research?

Random assignment ensures that participants are evenly distributed across experimental conditions, making the groups equal ahead of time and allowing for a clearer determination of causality.

What might an experimenter do to ensure the conditions are the same for all participants?

The experimenter can control variables such as the environment, instructions, and timing, ensuring everything is the same except for the independent variable being tested.

How does random assignment help in determining causality in an experiment?

By making the groups equal ahead of time, random assignment allows any differences observed after the manipulation of the independent variable to be attributed to that variable, thus helping to establish causality.