Experimental methods- Research methods Flashcards
What does experimental method mean?
Involves the manipulation of an independent variable to measure the effect on the dependent variable. Experiments may be laboratory, field, natural or quasi.
What does aim mean?
A general statement of what the researcher intends to investigate the purpose of the study
What does hypothesis mean?
A clear, precise, testable statement that states the relationship between the variables are to be investigated. Stated at the outset of any study.
What does directional hypothesis?
Sates the direction of the difference or relationship
What does non-directional hypothesis?
Does not state the direction
What does variable mean?
Any ‘thing’ that can vary or change within an investigation. Variables are generally used in experiments to determine if change in one thing results change to another.
What does an independent variable mean?
Some aspect of the experimental situation that is manipulated by the researcher- or changes naturally- so the effect on the DV can be measured.
What does a dependent variable mean?
The variable that is measured by the researcher. Any effect on the DV should be caused by the changes in the IV.
What is the aims of the experimental method?
In psychological research, aims are developed from theories.
Give an example of an aim:
To investigate whether drinking energy drinks makes people more talkative.
Give an example if a case:
We have a theory that energy drinks affect how much people talk. This is based on our understanding (having researched studies ) that energy drinks containing sugar and caffeine, and that these substances increase alertness making people chattier. A new energy drink has come into the market and we’re keen to know whether it might affect the talkativeness of those who drink it.
When is a hypothesis written?
Having written an aim, we need to now write a hypothesis.
What is a hypothesis and give an example?
A hyothesus is a statement that is made at the start if a study and clearly states the relationship between variables as stated by the theory. An example would be in this case: Drinking Speedup (an energy drink) causes people to become more talkative.
What can a hypothesis be?
Directional
Non directional
What is directional hypothesis?
In a directional hypothesis the researcher makes clear the sort of difference that is anticipated between two conditions or two groups of people. For this reason, directional hypothesis includes words like more or less, higher or lower, faster or slower.
Give examples of a directional hypothesis:
People who drink speed up become more talkative than people who don’t
People who drink water are less talkative than people who drink Speedup
What is a non directional hypothesis?
A non directional hypothesis simply states that there is a difference between the conditions but unlike a directional hypothesis, the nature of the difference is not specified.
Give an example of a non directional hypothesis:
People who drink Speedup differ in terms of talkativeness compared with people who don’t drink speed up.
-There will be a difference in how many numbers are correctly recalled by children and adults.
How do you do an experiment?
Firstly we are going to gather together two groups of people, lets say 10 in each group ( mostly because the total number of participants are 20) Then starting with the first group we will give the participants a can of speedup to drink. The participants in the other group will just have water. We will then record how many words each participant says in a five minute period immediately after they’ve had their drink.
How do you decide which hypothesis to use?
Psychologist tend to use directional hypothesis when the finding of previous studies suggest a particular outcome.
When there is no previous research or findings from earlier studies they will then use non directional hypothesis.
What are the independent and dependent variables?
-IV- Variable that is manipulated/ changed
- DV- Variable that is measured- researcher records the affect of the OV on the DV
All other variables that might potentially affect the DV should remain constant in a properly run experiment. This is so the researcher can be confident that the cause of the effect on the DV was the IV and the IV alone.
What are the levels of the IV?
In order to test the effect of the IV we need different experimental conditions. If we simply gave the participants Speed-up, how would we know how talkative they were? We need a comparison. We could either:
- Compare participants talkativeness before and after they drank speedup
- Compare two groups of participants- those who drank speedup up and those who drank water.
These are the two levels of IV: control condition (no Speedup? drink of water and the experimental condition (energy drink).
Give an example of a hypothesis that hasn’t been operationalised:
The group that drinks an energy drink will be chattier than the group that drinks water
What is operationalisation of variables?
Clearly defining each variable in the hypothesis
Give an example of an operationalised hypothesis?
After drinking 300ml of Speedup participants say more words in the next five minutes than participants who drink 300ml of water.
