1. How science works

2. Introduction Psychology is the science of mind and behaviour.
Because scientific methods are rigorous and respected it is important that psychology follows the basic scientific principles outlined in this presentation.

3. Cause and effect
One of the most important concepts that is looked for in psychology is cause and effect.
Cause and effect is how one variable can have an effect on another variable. For example, you could research how eating vegetables will have an effect on a person’s energy levels.
In experiments, we look for how the independent variable can have an effect on the dependent variable.
However, correlations only reveal relationships between variables and not how one variable will have an effect on another.

4. Falsification
‘The aim of science is not to open the door to infinite wisdom, but to set a limit to infinite error.’
B. Brecht

5. Falsification
To be scientific, psychological ideas and hypotheses need to be falsifiable.
This means that you should be able to conduct tests to see if research questions can be proved false.
For example, a research question like ‘Are all swans white?’ is falsifiable as you can test this claim and see if it’s true or not.
However ‘Does God exist?’ is not falsifiable as you cannot scientifically prove this right or wrong.
In modern psychology most research is falsifiable and can be tested scientifically. Some research, however, like Freud’s theory of the unconscious, is not falsifiable. This makes it unscientific.

6. Hypothesis testing
One way in which you can provide falsifiability in psychology is to write good hypotheses.
All psychological hypotheses should be able to be clearly tested.
For example, ‘Children will be significantly more intelligent after reading books’ is not a clearly testable hypothesis.
A way to make hypotheses clearly testable is by operationalising the variables so they are clear and specific.
For example, ‘Children will score significantly higher on a standard IQ test after having read at least five books in a year when compared to children who have read four books or fewer in a year.’
Because this hypothesis has its variables clearly operationalised, anyone could test it to see if it is true.

7. Manipulation of variables
In psychological experiments there are independent and dependent variables.
Dependent variables are what is being measured.
Independent variables should be able to be clearly manipulated.
For example, if you were researching whether alcohol impairs speech, you could clearly manipulate the amount of alcohol you give to different participants.

8. Replicability
Replicability is the ability to be able to repeat research again and again to see if the same results will keep happening.
Different researchers should be able to repeat the same research and obtain the same results.
If research is replicable it tends to be precise and detailed – this is one of the reasons why replicability is a key scientific principle.
Think of the research you’ve looked at so far. Could you repeat it? If not, why not? Look at Activity 1 of your worksheet.

9. Control and standardisation
A way in which you can ensure that research is replicable is to control it.
Controls mean making a study constant and keeping it the same for each participant who takes part in it.
This could include making sure all participants have the same time to complete a task, and that they complete the same task and follow instructions in the same order.
When a procedure has a clear set of instructions to follow, we can say that it is standardised. This means there is a standard way of carrying out the study.
A clearly standardised study should mean that anyone could read the procedure instructions and carry out the study themselves. This will make the study more replicable and therefore more scientific.

10. Objectivity
Studying human behaviour can be quite personal. It is often easy for researchers to look at things from their own point of view and be influenced by personal experience, morals and beliefs (subjectivity).
When people are subjective they are prone to bias, which can lead to recording inaccurate results.
Being objective means conducting research in a completely neutral way that eliminates all biases, emotions and feelings.
Ways to improve objectivity may be to use independent researchers to analyse results from participants they have never met.
You could also use researchers who are blind to the purpose of the research, to guarantee they will not be biased when researching.

11. Deduction
Psychological research relies on drawing conclusions from evidence.
If you deduce then you come to a conclusion by eliminating other possibilities until you are left with one.
For example, if researching why a child acts aggressively, there are lots of possible reasons for this. A scientist would try to eliminate as many reasons as possible and deduce the main cause for aggression.
Deuce = Reduce

12. Induction
Induction is when you generalise a limited finding to a larger population.
For example, a researcher may observe in a single cafe that the time people most often buy cappuccinos is between 4pm and 5pm and so induce that people in all cafes in that city tend to buy cappuccinos at the same time.
Induce = increase

13. Quantifiable results
Psychology researches concepts that are difficult to make scientific, e.g. emotions, memories and feelings.
Scientific results are usually numbered and quantitative. This is good as results can easily be compared and analysed.
A challenge in psychology is to take human concepts like memory and make them quantifiable (turn them into numbers).
How can you take a concept like memory and make it measurable through numbers?
You could use a memory test where participants look at a list of 30 words and write down as many as they can remember.
Think about concepts in the human mind that you could make quantifiable. Use the worksheet for Activity 2 to help you.

14. Pick a psychological study Explain how scientific it is using one these key words
Cause and effect
Control and standardisation
Falsification
Objectivity
Hypothesis testing
Deduction
Manipulation of variables
Induction
Replicability
Quantifiable
Make a top trump card for a study you have learnt with these features
Play top trumps and decide who wins each turn through negotiation!
Can you decide which is the most scientific study?