Introduction to Aims and Hypotheses
Welcome to the very beginning of any psychological investigation! Before a psychologist starts collecting data, they need a clear plan. Think of it like going on a road trip: the Aim is your destination (where you want to go), and the Hypothesis is your prediction of what you will find when you get there. Understanding these is vital for your Paper 2 and Paper 4 exams, where you will often be asked to identify or write them yourself.
Don't worry if these terms sound a bit scientific at first—by the end of this page, you’ll be able to write them like a pro!
1. What is an Aim?
An aim is a simple, broad statement that explains the purpose of the study. It tells the reader what the psychologist is investigating.
Example: In the core study by Andrade (2010), the aim was to investigate whether doodling aids (helps) concentration while listening to a boring message.
Key Takeaway: Aims usually start with the words "To investigate..." or "To see if...". They are general and do not usually include specific predictions about the results.
2. What is a Hypothesis?
A hypothesis (plural: hypotheses) is a formal, testable prediction about the outcome of the study. Unlike an aim, which is a general goal, a hypothesis makes a specific claim about the relationship between variables.
In Psychology, we use two main types of hypotheses: the Alternative Hypothesis and the Null Hypothesis.
A. The Alternative Hypothesis
This predicts that there will be a significant effect, difference, or relationship. There are two "flavours" of alternative hypotheses:
Directional (One-tailed) Hypothesis
This predicts the specific direction of the results. You use words like more, less, faster, slower, higher, or lower.
Analogy: It’s like saying, "I predict my team will win by 2 goals." You aren't just saying they will play; you are saying exactly how they will do.
When to use it: Researchers use this when previous research or theories suggest which way the results will go.
Non-directional (Two-tailed) Hypothesis
This predicts that there will be a difference or effect, but it doesn’t say which way it will go. You use words like "There will be a difference..." or "There will be an effect...".
Analogy: It’s like saying, "I predict the score will not be a draw." You know something will happen, but you aren't sure who will win.
When to use it: Researchers use this when the topic is brand new or when previous studies have found conflicting results.
B. The Null Hypothesis
The null hypothesis predicts that there will be no significant difference or relationship. Any difference found is just due to chance.
Example: "There will be no difference in memory scores between participants who doodle and participants who do not doodle."
Quick Review Box:
Aim: What are we doing?
Directional: Predicting a specific winner/direction.
Non-directional: Predicting a change, but not sure which way.
Null: Predicting "nothing happens."
3. How to Write a High-Scoring Hypothesis
To get full marks in your exam (especially in Paper 4), your hypothesis must be operationalised. This means you must clearly define the variables so they are measurable.
Checklist for a great hypothesis:
1. Mention both levels of the Independent Variable (IV).
2. Mention the Dependent Variable (DV).
3. Make sure the DV is measurable.
Note: For more on how to define these, see the chapter on "Variables and operationalisation."
Common Mistake to Avoid: Many students forget to mention the second group.
Incorrect: "People who drink coffee will be faster." (Faster than who?)
Correct: "Participants who drink 200ml of coffee will complete a puzzle faster than participants who drink 200ml of water."
4. Hypotheses in Correlational Studies
Correlational studies are different because they don't have an IV or DV. Instead, they have two co-variables. Because of this, the wording changes slightly.
Important Rule: Never use the words "cause," "affect," or "difference" in a correlational hypothesis. Instead, use the word relationship or correlation.
Example (Directional Correlation): "There will be a significant positive correlation between the number of hours spent studying and the score achieved on a Psychology test."
Key Takeaway: Correlations measure how two things change together. They do not prove that one thing causes the other.
5. Exam Tips for AS & A Level
Paper 2 (Research Methods)
In Paper 2, you might be asked to identify a hypothesis from a scenario. You also need to know that in the "Planning" section of Paper 2, you are not required to write an aim or hypothesis for your plan. However, you must know how they work to answer the short-answer questions!
Paper 4 (Specialist Options)
In Paper 4, when you design a study, you must include both an aim and a hypothesis. This is where being specific and operationalising your variables becomes very important for your marks.
A Level Concept: Temporal Validity
While this is covered more in the "Validity" chapter, remember that if a study's aim or hypothesis is based on social settings from 50 years ago, we must ask if the prediction still holds true today. This is called temporal validity.
Summary Review
Did you know? Psychologists always start by assuming the Null Hypothesis is true. They only reject it if their data shows a strong enough effect. It's like the legal principle of "innocent until proven guilty"!
Key Points Checklist:
- Aim: General purpose (To investigate...)
- Hypothesis: Specific, testable prediction.
- Directional: States the expected direction (e.g., higher).
- Non-directional: States there will be a difference but not which way.
- Null: States there will be no difference/relationship.
- Operationalisation: Making variables measurable for the hypothesis.