Welcome to Your Practical Investigations!
In Psychology, we don't just read about how people behave; we go out and find out for ourselves! Practical investigations are the "hands-on" part of your OCR A Level course. This chapter is all about how you plan, conduct, and explain your own research. Think of it like being a detective: you have a question, you gather evidence, and you try to solve the mystery of human behavior.
Don't worry if this seems a bit overwhelming at first. We are going to break down the four main ways you will "do" psychology and look at how to stay ethical and organized while doing it.
1. The Four Core Methods
The OCR syllabus requires you to conduct your own small-scale versions of four specific types of research. You need to be ready to talk about these in your exam, explaining what you did, what you found, and how you could have done it better.
A. The Experiment
An experiment is used to find out if one thing causes another. You change one thing (the Independent Variable) to see if it affects something else (the Dependent Variable).
Example: Does listening to music while studying (IV) make your test scores (DV) better or worse?
B. The Observation
An observation involves watching and recording behavior as it happens. You aren't changing anything; you are just being a "fly on the wall."
Example: Counting how many students use their phones in the cafeteria during lunch.
C. The Self-Report
A self-report is when you ask people to tell you about their own thoughts, feelings, or behaviors using questionnaires or interviews.
Example: Giving a survey to your classmates about their stress levels before an exam.
D. The Correlation
A correlation looks for a relationship or link between two variables. Unlike an experiment, you aren't saying one thing causes the other; you are just seeing if they move together.
Example: Is there a link between the number of hours you spend on social media and how happy you feel?
Quick Review: - Experiment: Testing cause and effect. - Observation: Watching behavior. - Self-Report: Asking people directly. - Correlation: Finding a link between two things.
2. Planning Your Investigation
Before you start, you need a solid plan. A messy plan leads to messy data!
Aims and Hypotheses
Your Aim is a general statement of what you intend to study (e.g., "To investigate the effect of sleep on memory").
Your Hypothesis is a clear, testable prediction. You need to know two main types:
1. Alternative Hypothesis: Predicts that there will be a significant difference or relationship.
2. Null Hypothesis: Predicts that there will be no significant difference or relationship. It's basically saying, "Nothing interesting will happen here."
Choosing Your Participants (Sampling)
You can't study everyone in the world! You pick a sample from your target population. Common ways to do this include:
- Opportunity Sampling: Using whoever is available at the time (like people in the library right now).
- Self-Selected Sampling: Putting up a poster and waiting for volunteers to come to you.
Memory Aid: Think of a Sample like a "taster" spoonful of soup. It's a small bit used to tell you what the whole pot (the Target Population) tastes like!
3. Staying Ethical: The Rules of the Game
In Psychology, we must treat our participants with respect. The British Psychological Society (BPS) has four main principles you must follow in your practicals:
1. Respect: This includes Informed Consent (telling them what they will be doing) and Confidentiality (keeping their names secret).
2. Competence: You should only conduct research you are qualified to do.
3. Responsibility: You must protect participants from harm and debrief them (explain the true aim of the study afterward).
4. Integrity: Being honest and avoiding deception unless it's absolutely necessary for the study.
Did you know? If you ever use animals in research, you must follow the 3Rs: Replacement (use a non-animal alternative if possible), Reduction (use as few animals as possible), and Refinement (make sure they suffer as little as possible).
4. Analyzing and Presenting Your Results
Once you've done your research, you'll have a pile of "raw data." You need to turn this into something people can understand.
Descriptive Statistics
These help you summarize your findings:
- Mean: The average (add all scores together and divide by the number of scores).
- Median: The middle score in a list ordered from lowest to highest.
- Mode: The most common score.
- Range: The difference between the highest and lowest score.
Visualizing Data
Choose the right graph for your method: - Bar Charts: Great for comparing different groups in an experiment. - Scatter Diagrams: Essential for showing the relationship in a correlation.
Quick Review Box: - Use a Mean when you have a lot of data and want a sensitive average. - Use a Median if you have one or two very weird, extreme scores (outliers) that might mess up the average. - Correlation Coefficients are numbers between \( -1 \) and \( +1 \) that tell you how strong a relationship is.
5. Writing Up Your Report
In your exam, you might be asked about the sections of a psychological report. They usually go in this order:
1. Abstract: A tiny summary of the whole thing.
2. Introduction: Why you are doing the study and what others have found.
3. Method: The "recipe" — how you did it (Design, Sample, Materials, Procedure).
4. Results: What the numbers showed (graphs and stats).
5. Discussion: What the results mean and how to improve the study.
6. References: Giving credit to other researchers.
7. Appendices: Extra stuff like copies of your questionnaire or raw data tables.
Common Mistakes to Avoid
- Confusing Correlation with Causation: Just because two things are linked (like ice cream sales and shark attacks) doesn't mean one causes the other! (In this case, it's just that both happen in hot weather).
- Vague Hypotheses: Make sure your hypothesis mentions both variables clearly. Instead of saying "Music affects memory," say "Participants who listen to classical music will remember more words than those who sit in silence."
- Forgetting the Debrief: In ethical questions, always mention that participants should be told the true aim of the study once it's over.
Key Takeaway
Practical investigations are about applying the rules of science to human behavior. Whether you are conducting an experiment, an observation, a self-report, or a correlation, your job is to be objective, ethical, and organized. If you can explain what you did and why you did it, you're well on your way to success!