Research methods Flashcards
What is an Independant Variable?
Some event that is directly manipulated by experimenter in order to test its effect on the DV.
What is a Dependant Variable?
A measurable outcome of the action of the independent variable in an experiment.
What is an extraneous Variable?
Variables which may effect the dependant variable but do not act as an independent variable. Nuisance variables that muddy the waters and make it more difficult to detect a significant effect.
What is Mundane realism?
How an experiment mirrors the real world. ‘Mundane’ means ‘of the real world’ - commonplace, ordinary.
What does Control mean?
Refers to the extent which any variable is held constant or regulated by a researcher.
What is External validity?
The degree to which a research finding can be generalised: to other settings (ecological validity); other people (population validity); over time (temporal/historical validity).
What is internal validity?
The degree which an observed effect was due to the experimental manipulation rather than other factors such as confounding/extraneous variables.
What does Validity mean?
Refers to whether an observed effect is a genuine one.
What is a confounding variable?
A variable under study that is not the IV but which varies systematically with the IV.
What does confound mean?
To cause confusion.
What is a laboratory experiment?
An experiment conducted in a special enviroment where variable can be carefully controlled.
What is a field experiment?
An experiment conducted in a more natural enviroment i.e. in ‘the field’.
What are strengths of Laboratory experiements?
- Usually high in internal validty because extraneous variables can be controlled.
What are limitations of Laboratory experiements?
- Participants usually are aware that their behaviour is being studied. Leading to particpants searching for cues about the aims of the experiments and affect behaviour reducing realness.
- The IV and DV may be operationalised in such a way that it doesn’t represent everyday experiences, i.e low in mundance realism.
- Low ecological validty can also be explained in terms of setting. Participants may feel uncomfortable in an unknown and artifical enviroment. Causes change in usual behaviour.
- Materials may lack mundane realism.
What are strengths of Field experiments?
- Participants are not likely to be aware that their behvaiour is being studied
- A field experiment takes places in a more natural setting (e.g a classroom), particpants are more relaxed.
What are limitations of Field experiments?
- It is more difficult to control extraneous variables.
- There is a major ethical issue
What is a Natural Experiment?
An experiment conducted when it is not possible, for ethical or practical reasons, to deliberately manipulate an IV.
What are the strengths of Natural experiments?
- Allows research where IV can’t be manipulated for ethical or practical reasons.
- Enables researchers to study ‘real’ problems such as the effect of a disaster on health (increased mundane realism and ecological validty).
What are limitations of Natural experiments?
- Cannot demomstrate causal relationships because IV not directly manipulated.
- Can only be used where conditions vary naturally.
- Participants may be aware of being studied, creating demand characteristics and reducing internal validity.
- The DV may be a fairly artficial task, reducing mundane realism.
What is strength of Quasi-experiments?
Allows comparisons between types of people.
What are limitations of Quasi-experiments?
- Participants may be aware of being studied, creating demand characteristics and reducing internal validty.
- The DV may be a fairly artificial task, reducing mundane realism.
Operationalise
Ensuring that variables are in a form that can be easily tested. E.g a GCSE maths grade.
Hypothesis
A precise and testable statement which is based on an assumption of a relationship between variables.
Aim
An statement of what the reseacher intend to find out in a research study.
What is an experiment?
A research method where causal conclusions can be drawn because an IV has been deliberatley manipulated to observe the casual effect on the DV.
What are Standardised procedures?
A set of procedures that are the same for all p’s in order to be able to repeat the study.
Debriefing
A post-research interview designed to inform participants of the true nature of the study and to restore them to the state they were in a the start of the study.
What is Counterbalancing?
An experimental technique usted to overcome order effects when using a repeated measures design.
What is a Experimental design
A set of procedures used to control the influence of factors as p’s variables in an experiment.
What is an independent groups design?
P’s are allocated to two (or more) groups representing different levels of IV. Allocation is usually done using random techiniques.
Matched pairs design
Pairs of p’s are matched in terms of key variabls such as age and IQ.
Random allocation
Allocating participants to experimental groups or conditons using random techniques.
Repeated measure design
Each p’s takes part in every conditon under test, I.e each level of the IV.
Order effect
In a repeated measure design an extraneous variable arising from the order in which conditions are presented. Eg fatigue effect
What are the strengths of Mean?
Most sensitive measure of central tendency as it includes all the raw data most suitable for interval or ratio data.
What are the limitations of Mean?
Can be biased by skewed (outlying) scores often means score is not one of the original scores (eg. 2.4).
Can not be representative of the data at all times eg average family size 2.4 children!
What is the strengths of Median?
- Not affected by extreme scores.
- Most appropriate for ordinal data
- quick and easy to calculate
- Can be more representative on a set of skewed scores
What is the limitations of Median?
- Not as sensitive as the mean.
- Not used in further statistical calculations
What are the strengths of Mode?
- Not affected by the extreme scores
- Can make more sense eg. average number of children in a family is 2 (mode) rather than 2.4
What is the limitations of Mode?
- Not v. useful if more than one modal score.
- Tells us nothing about the other scores
What is the definition of Case studies?
Detailed study of a single individual/small group by using a self-report and/or observational techniques.