Welcome to Research Methods!

Research methods are the "tools" that psychologists use to understand how humans think and behave. Think of it like a detective kit: before a psychologist can tell us why we forget things or why we follow a crowd, they need to know how to gather evidence properly. Don't worry if some of this seems like math or science at first—we will break it down into simple steps!

1. Starting with a Plan: Hypotheses

Before starting an experiment, a psychologist makes a prediction. This is called a hypothesis.

Types of Hypotheses:

1. Null Hypothesis: This predicts that there will be no difference or effect. It’s like saying, "Drinking coffee won't make you run any faster."
2. Alternative Hypothesis: This predicts that there will be a difference. For example, "Drinking coffee will make you run faster than drinking water."

Quick Review: The Null hypothesis is the "boring" one (nothing happens), while the Alternative hypothesis is the one testing a new idea.

2. The Building Blocks: Variables

In psychology, we change one thing to see what happens to another. These "things" are called variables.

Independent Variable (IV): The thing the researcher changes (the "cause").
Dependent Variable (DV): The thing the researcher measures (the "effect").
Extraneous Variables: These are "annoying" extra things that might mess up the results, like noise in the room or how tired a participant feels. Researchers try to control these so the test is fair.

Example Analogy: If you are testing if a new fertilizer helps plants grow, the Fertilizer is the IV and the Plant Height is the DV. A rainy day would be an extraneous variable!

3. Picking People: Sampling Methods

You can't study everyone in the world, so you pick a sample from a target population.

How to choose your sample:

• Random: Everyone has an equal chance (like pulling names out of a hat). It is very fair but can take a long time.
• Opportunity: You just ask whoever is available at the time (like people walking past you in the hall). It is quick but might be biased.
• Systematic: You use a system, like picking every 5th person on a list.
• Stratified: The sample reflects the exact proportions of the group (e.g., if the school is 60% girls, your sample is 60% girls). This is the most representative but very hard to do.

Key Takeaway: A good sample represents the whole group so the results are "true" for everyone, not just a few people.

4. Designing the Experiment

How do we organize our participants? There are three main ways:

Experimental Designs:

1. Independent Groups: Different people do different tasks. Group A drinks coffee; Group B drinks water.
Strength: No "order effects" (people don't get bored or practiced).
Weakness: The groups might be different naturally (e.g., Group A might just be naturally faster runners).

2. Repeated Measures: The same people do both tasks. Everyone drinks coffee on Day 1 and water on Day 2.
Strength: No "people differences" because it’s the same people!
Weakness: Order effects—people might do better on the second day just because they’ve practiced.

3. Matched Pairs: You find two people who are very similar (like twins or people with the same IQ) and put one in Group A and one in Group B.
Strength: Reduces person-to-person differences.
Weakness: Very difficult and time-consuming to find "matches."

5. Different Ways to Research

Psychologists don't just use experiments in labs. They have many methods:

• Laboratory Experiment: Done in a controlled room. High control but can feel "fake" to participants.
• Field Experiment: Done in the real world (like a shopping center). More natural, but harder to control extraneous variables.
• Natural Experiment: The researcher doesn't change the IV; it happens on its own (like comparing people before and after a new law is passed).
• Questionnaires & Interviews: Asking people for their thoughts. Questionnaires are fast; interviews give more detail.
• Case Studies: An in-depth study of just one person or a small group (often used for unique brain injuries).
• Observation Studies: Watching how people behave. Researchers use categories of behaviour (a checklist of what to look for). To make it fair, they use inter-observer reliability, which means two researchers watch and see if they agree on what they saw.

A correlation looks at the association between two variables. For example, does "Time spent revising" link to "Exam scores"?

• We show this using scatter diagrams.
• Positive Correlation: Both go up together (More revision = higher marks).
• Negative Correlation: One goes up, the other goes down (More time on video games = lower marks).
• Zero Correlation: No link at all (Shoe size has no link to IQ).

Important: Correlation does NOT mean one thing caused the other. It just shows they are linked!

7. Doing it Right: Procedures and Ethics

Researchers must follow strict rules to be fair and kind.

Procedures:

• Standardisation: Giving every participant the exact same instructions and experience.
• Randomisation: Using chance (like a coin flip) to decide things, like which group a person goes in.
• Counterbalancing: Used in repeated measures. Half the group does Task A then B; the other half does B then A. This cancels out the "order effects."

Ethics (The BPS Guidelines):

Psychologists must follow British Psychological Society (BPS) rules:
1. Informed Consent: Participants must agree to take part and know what they are doing.
2. Deception: You shouldn't lie to participants unless it's absolutely necessary.
3. Protection from Harm: Participants must not be embarrassed or hurt.
4. Privacy and Confidentiality: Keep their names and data secret.

8. Data Handling: The Numbers

Once the research is done, we have to look at the data.

Quantitative vs. Qualitative:

• Quantitative: Numbers (e.g., "7 out of 10 people"). Easy to graph.
• Qualitative: Words and descriptions (e.g., "I felt very nervous"). Gives deep meaning.

Primary vs. Secondary:

• Primary: Data you collected yourself for your own study.
• Secondary: Data collected by someone else (like looking at government statistics).

Descriptive Statistics:

You need to know how to calculate these four things:
1. Mean: The average (add them all up and divide by how many there are).
2. Median: The middle value when they are in order.
3. Mode: The most common value.
4. Range: The biggest number minus the smallest number.

Memory Aid: "The Mean is the 'mean' one because it makes you do the most math!"

Normal Distributions:

If you graph the height or IQ of a large population, it usually forms a Normal Distribution. This looks like a symmetrical "Bell Curve" where most people are in the middle and very few people are at the extreme ends.

Final Quick Review Box

• IV = What you change. DV = What you measure.
• Standardisation keeps it fair for everyone.
• Ethics keep participants safe.
• Mean, Median, Mode help us see the "average" person.
• Correlations show links, but NOT causes.