Research Methods Flashcards
(81 cards)
independent variable
The variable which changes or is manipulated
dependant variable
The variable that is measured to see the effect of the iv
operationalising
To be specific and clear when defining the independent and dependant variable in an experiment, to make it easier to measure
lab experiment
An experiment conducted in a highly controlled environment
the researcher manipulated the independent variable and measures the effect on the dependant variable
field experiment
Takes place in a natural environment such as an office or a school
the researcher manipulates the independent variable and measures the effect on the dependant variable
natural experiment
The researcher takes advantage of a naturally occurring IV (event)
strengths of a lab experiment
- High level over extraneous variables eg. Light. Cause and effect can be established which increases internal validity
- High in reliability as the experiment can be easily repeated in the same conditions to check for consistent results
What are weaknesses of a lab experiment ?
- lacks ecological validly as its carried our in an artificial setting. It is difficult to generalise the finding beyond the settings of the study, lowering its external validity.
- prone to demand characteristics where the participants behaviour changes according to clues given off by the researcher, reducing the internal validity
Strengths of a field experiment ?
- Less prone to demand characteristics. People might not know they are ring watched so are less likely to guess clues given off by the researcher and change their natural behaviour, increasing the internal validity
- high ecological validity as its based in a Real life setting therefore its easier to generalise the finding beyond the setting of the study, increasing the external validity
Weaknesses of a field experiment ?
- low in reliability as the environment is natural. It is difficult to repeat it with exactly the same conditions to check for consistent results
- could create an ethical issue with lack of informed consent as people may not be aware they are being studied. If they become aware of this they may become upset and wish to withdraw their data from the research
Strengths of a natural experiment ?
- Provides opportunities for research that may not be undertaken for practical or ethical reasons
- high ecological validity as the natural experiments are often base in a real life setting. It’s easier to generalise the findings beyond the setting increasing the external validity
Weaknesses of a natural experiment ?
- Naturally occurring event may only happen very rarely which limits the opportunities for research
- low control ver extraneous variables as natural experiment take place in a natural environment. It is difficult to establish cause and effect between the IV and DV lowering the internal validity
independent group design
Participants take part in one condition only. Each condition has a different group of participants
Conducted
- Participants are recruited
- They are split into equal sized groups
- A different group is allocated each condition
advantages of an independent group design experiment ?
- No order effects because participants only take part in one condition so they wont get fatigued, bored or better at the task
dis-advantages of an independent group design experiment ?
- individual differences may affect the DV as there are separate groups of participants in each condition.
- more participants are needed as two different groups are required for different conditions
repeated measures design
All participants take part in all/both conditions of the experiment
Conducted
- participants complet one condition
- after a specific time lapse they will repeat the other condition
- the task should be different but matched on difficulty/measuring the same thing
advantages of a repeated measure design in an experiment ?
- Requires fewer participants
- same participants take part in all conditions. The researcher can be more sure that any changes in the DV are due to the IV and not any other variable
dis-advantages of a repeated measure design in an experiment ?
- order effects may occur when participants take part in more than one condition. They may perform worse in the second activity from being tried (reduces internal validity)
- increase chances of demand characteristics as participants take part in all conditions and may pick up clues given off by the researcher
matched pairs design
Participants are matched on important characteristic and then each pair is randomly allocated across each condition
Conducted
- choose a variable to match the participants on
- test the ppt on this variable before the study
- match the ppts with the same scores
- randomly allocate each member of the pair to one condition
advantages of matched pairs design in an experiment ?
- reduces individual differences between participants researcher can be sure that changes in the dv are due to the iv and not other variables
- no order affects because ppts only take part in one condition so they wont get bored or fatigued
dis-advantages of matched pairs design in an experiment ?
- very time consuming to match up and find similar ppts. You would need a very large pool of people
- individual differences could not be fully eliminated you could question validity
How do you find the mean of a set of numbers ?
Add all of them together and divide them by the amount of numbers added together
How do you find the mode of a set of numbers ?
It is the most common number
How do you find the range of a set of numbers ?
Subtract the smallest number from the largest number