Welcome to the World of Psychological Research!
Ever wondered how psychologists actually "prove" things? They don't just guess; they use a specific set of tools called Scientific Processes. This chapter is the "toolbox" of psychology. Once you understand these tools, you'll be able to look at any study and understand exactly how it was built. Don't worry if it seems like a lot of terms at first—we'll break them down step-by-step!
1. Starting with a Plan: Aims and Hypotheses
Before a psychologist starts any study, they need to know what they are looking for.
Aims vs. Hypotheses
An Aim is a general statement of what the researcher intends to investigate. Think of it as the "goal" of the study.
Example: "To investigate if drinking coffee affects concentration."
A Hypothesis is a clear, precise, and testable statement that predicts the outcome of the study. It’s like a specific bet the researcher is making.
Types of Hypotheses
Directional Hypothesis: This predicts the specific direction of the results. Use this when previous research suggests which way the results will go.
Example: "Students who drink coffee will score higher on a concentration test than those who don't."
Non-directional Hypothesis: This predicts that there will be a difference, but doesn't say which way it will go. Use this when there is no previous research or findings are mixed.
Example: "There will be a difference in concentration scores between students who drink coffee and those who do not."
Quick Review:
• Aim: What are we doing?
• Hypothesis: What do we think will happen?
• Directional: Higher/Lower, Faster/Slower.
• Non-directional: Just a "difference."
2. Choosing Your People: Sampling
Psychologists can't study every single person in the world. Instead, they use a Sample.
The Population: The large group of people the researcher is interested in (e.g., "all teenagers in the UK").
The Sample: The smaller group of people who actually take part in the study.
Sampling Techniques
1. Random Sampling: Every member of the population has an equal chance of being chosen (like pulling names out of a hat).
• Pro: It is usually unbiased.
• Con: It can be very time-consuming.
2. Opportunity Sampling: The researcher simply asks whoever is available at the time (e.g., asking people in the school cafeteria).
• Pro: It’s quick and easy.
• Con: It is often biased because the sample might not represent the whole population.
Generalisation
If your sample is "representative" (looks like the target population), you can generalise. This means you can say, "Because it happened to my sample, it probably happens to everyone in the population."
3. Designing the Experiment
How do we organize our participants into groups? There are three main Experimental Designs.
1. Independent Groups
Participants are split into two groups. One group does Condition A (e.g., coffee), and the other does Condition B (e.g., water).
• Mistake to avoid: Don't forget that you need to use Random Allocation here to make sure the groups are fair!
2. Repeated Measures
The same participants do both Condition A AND Condition B.
• The Problem: Order Effects. Participants might get better at the task because they've practiced it, or worse because they are bored.
• The Fix: Counterbalancing. Half the group does A then B, the other half does B then A. (Think: ABBA!)
3. Matched Pairs
Participants are paired up based on something important (like IQ or age). One person from the pair does Condition A, and the other does Condition B.
• Analogy: Imagine trying to test a new running shoe. You’d pair two runners with similar fitness levels so the "shoes" are the only real difference.
4. The Variables: The "Moving Parts"
Independent Variable (IV): The thing you change or manipulate (the "cause").
Dependent Variable (DV): The thing you measure (the "effect").
Operationalisation
This is a fancy word for making variables measurable. You can't just measure "intelligence"; you have to operationalise it as "a score on a 20-question IQ test."
Extraneous Variables
These are "annoying" extra variables that might mess up your results (like a loud noise outside during a test). If they aren't controlled, they become confounding variables.
Did you know?
Demand Characteristics happen when participants try to guess the aim of the study and change their behavior to "help" or "mess with" the researcher. It's like when you act differently because you know your teacher is watching you!
5. Pilot Studies
A Pilot Study is a small-scale "practice run" of the investigation.
Why do it? To check if the timing is right, if the instructions are clear, and to see if the whole thing works before spending lots of money on the real study.
6. Other Ways to Collect Data
Experiments aren't the only tool in the box!
Observational Design
Psychologists watch people. To make it scientific, they use Behavioural Categories. Instead of just "watching a child play," they tick a box every time the child "shares a toy" or "hits a peer." This makes the observation objective.
Self-Report Techniques
Questionnaires:
• Open questions: Allow participants to answer in their own words (provides qualitative data).
• Closed questions: Fixed choices like "Yes/No" or a scale of 1-10 (provides quantitative data).
Interviews:
• Structured: Pre-set questions in a fixed order.
• Unstructured: More like a conversation; questions are developed based on the answers given.
7. Ethics: Doing the Right Thing
Psychologists must follow strict ethical guidelines to protect participants. Use the mnemonic "Can Do Can't Do With Participants" to remember some of the big ones!
• Confidentiality: All personal data must be kept private.
• Informed Consent: Participants must know what they are signing up for.
• Deception: You shouldn't lie to participants (unless it's absolutely necessary and justified).
• Debrief: After the study, tell the participants the true aim and make sure they are okay.
• Right to Withdraw: Participants can leave at any time.
• Protection from Harm: Participants must not be embarrassed, stressed, or physically hurt.
• Privacy: Do not observe people in private places (like their homes) without permission.
Key Takeaway:
Scientific psychology is all about control and fairness. By using specific aims, controlled variables, and ethical practices, we can trust that the results of a study are actually true!