Research Methods Flashcards
(103 cards)
What Is a hypothesis?
Is a prediction and testable statement of the relationship between 2 variables
What are the 2 types of hypotheses?
Directional (one-tailed)
Non-directional (two-tailed)
What is a directional hypothesis? (One tailed)
This predicts that the nature of the effect of the IV in the DV
-predicts the direction in which results are expected to occur. (Correlation would either be positive or negative)
What is a non-directional hypothesis? (Two-tailed)
This predicts that the IV will have an effect on the DV, but the direction of the effect is not specified
-predicts a difference but not a ‘direction’ of difference (there would be a correlation but not specified whether positive or negative)
What is a dependent variable?
Is the variable that the experimenter measures and it depends on the IV
What is an independent variable?
Is the variable that the experimenter manipulates
What must variables always be?
Operationalised
What does operationalising a variable mean?
Putting the variables into a form, that can be easily tested, so defining them as precisely as possible
What are the 4 types of experiments?
- Laboratory
- field
- quasi
- natural
define what a lab experiment is?
An experiment conducted in an environment where the variables are carefully controlled
-participants are aware that they are taking part in an experiment, although they may not know the true aim of the study
Give an example of a lab experiment
Milgrams study on obedience (1963)
Give 2 advantages of laboratory experiments
- a high degree of control over the variables minimises any extraneous variables, leading to higher internal validity and a greater likelihood of establishing a cause and effect relationship
- greater potential for replicability as the study is carefully designed and variables are highly controlled, allowing other researchers to check for similar results
Give 3 disadvantages of laboratory experiments
- they are artificial
- risk of demand characteristics
- low ecological validity as participants may not behave naturally
Define what is meant by field experiments
IV manipulated by researcher. Carried out in everyday settings (more realistic than lab)
Give an example as to when a field experiment was used
Hofling et al(1966) - investigated obedience in a hospital setting. 22 nurses were telephoned by a ‘doctor’ who asked them to administer a drug they’d never heard of. The nurses were unaware they were participating in the study
Give 2 advantages of field experiments
- behaviour is more realistic. Ecological validity higher than lab experiments
- everyday behaviour
Give 3 disadvantages of field experiments
- less control over extraneous variables, because the study takes place in the real world, therefore reducing the internal validity of the study
- potentially more time consuming and expensive
- problems with replicability
Define what is meant by natural experiments
A natural experiment is conducted when it is not possible for ethical or practical reasons, to deliberately manipulate the IV. Therefore it is said that the IV varies naturally. The DV may be tested in the lab
Give an example of when a natural experiment was used
Effects of institutionalisation-
A study looking at the effects of being adopted either before 6 months or after
Give 3 advantages of using natural experiments
- reduced demand characteristics
- good method to use if topic is a sensitive ‘ethical issue’
- very high levels of ecological validity
Give 2 disadvantages of using a natural experiment
- difficult to show cause and effect(IV-DV)
- researcher does not control IV and does not allocate Ps to conditions
Define what is meant by a quasi experiment
An experiment where the IV is naturally occurring and the DV may be measured in the lab. The IV could not be made to vary by anyone the difference is fixed (e.g. Males/females
Give 1 advantage of quasi experiments
-allows for comparison between different types of people
Give 1 disadvantage of quasi experiments
-participants may be aware of being studied, this will reduce the internal validity (e.g. What you are measuring in your study)