Formulation of Testable Hypotheses (OCR GCSE Psychology): Revision Note
Exam code: J203
The alternative hypothesis
A hypothesis is a testable statement that predicts what the researcher expects to find in their study
The psychologist’s goal is to test the hypothesis and find out whether supports the data
The alternative hypothesis predicts a pattern in results, either:
a difference between two or more conditions, or
a correlation between two variables
It must include both the independent variable (IV) and the dependent variable (DV)
Both variables must be operationalised – clearly defined and measurable, e.g.
IV: Exposing some children to an aggressive adult model while others are exposed to a non-aggressive adult model
DV: Counting the number of acts of aggression performed by the child
Examples of alternative hypotheses
When predicting a difference, the researcher needs at least two conditions or groups of participants to compare, e.g.
“There will be a difference in the number of aggressive acts performed by children, depending on whether they have been exposed to an aggressive adult model or a non-aggressive adult model"
When predicting a correlation, the researcher must include both co-variables that they are investigating for a possible relationship, e.g.,
“There will be a correlation between how many hours participants have slept and how stressed they rate themselves on a scale of 1 to 10”
Examiner Tips and Tricks
Examiners note that students often confuse concepts such as correlation and difference.
Be precise in your wording, and when you’re asked to write a hypothesis, make sure it clearly matches the type of investigation.
For example, if the study is testing a relationship, you should state, “There will be a correlation…” rather than describing a difference.
The null hypothesis
All psychological research must include a null hypothesis
The null hypothesis predicts no difference or no correlation between variables
It is written before running the experiment because the results are not yet known
In research, either the null or alternative hypothesis will be supported
The psychologist’s job is to find out which hypothesis is correct, and reject the one that is not supported
Examples of null hypotheses
When predicting no difference:
“There will be no difference in the number of aggressive acts performed by children, depending on whether they have been exposed to an aggressive adult model or a non-aggressive adult model"
When predicting no correlation or relationship:
“There will be no correlation between how many hours participants have slept and how stressed they rate themselves on a scale of 1 to 10”
Accepting and rejecting hypotheses
If there is no significant difference or correlation, the null hypothesis is accepted, and the alternative hypothesis is rejected
If there is a significant difference or correlation, the null hypothesis is rejected, and the alternative hypothesis is accepted
Examiner Tips and Tricks
It is essential not to confuse the alternative hypothesis with the null hypothesis. One way of remembering which is which is to remember that ‘null’ means ‘nothing’, i.e. no difference or correlation between the conditions.
Worked Example
Here is an example of an A02 question you might be asked on this topic.
AO2: You need to apply your knowledge and understanding, usually referring to the ‘stem’ in order to do so (the stem is the example given before the question).
Professor Gunner believes that drinking cola before a football match improves players’ ability to score penalties. He decides to test this by comparing the performance of players who drink cola with those who do not.
Q. State a null hypothesis for this investigation.
[2 marks]
Model answer:
There will be no difference in the number of goals scored (the DV) depending on whether football players have drunk cola or not drunk cola (the IV) before attempting the penalties [2 marks].
Unlock more, it's free!
Did this page help you?
