Research methods Flashcards
Define experiment
Tests undertaken under controlled conditions in order to investigate the effect of the IV on the DV
Define lab experiment
Experiments that occur in a highly controlled setting where the experimenter directly manipulates the IV
Define field experiment
Experiments that occur in a natural environment of the people whose behaviour is being studied
Define quasi experiment
Where the IV is naturally occurring as opposed to be created and controlled by the experimenter
List the strengths of lab experiments
Control in a lab experiment will produce scientific research, which ensures that the variable which we are manipulating is the only thing affecting behaviour (ie no extraneous variables)
List the weaknesses of lab experiment
Lower EV as they are artificial settings which do not reflect real life, so therefore the behaviour seen may also be artificial
What are the strengths of a field experiment?
More realistic setting for a study and can have higher EV
What are the weaknesses of a field experiment?
Lack of control can mean it is difficult to assume the IV was actually influencing behaviour and that it wasn’t another extraneous variable
What are the strengths of quasi experiments?
Allows us to study the effects of the variables psychologists can’t manipulate or change behaviour
What are the weaknesses of quasi experiments?
There is no control over the participants, in terms of social setting, how they were brought up, lifestyle etc., and these may be confounding variables which can influence behaviour
Define repeated measures
This involves using the same P’s in each condition
Define independent measures
This involves using different people in each condition
Define matched groups
This involves using different people in each condition but an attempt is made to make the P’s as similar as possible on certain key characteristics
What are the advantages of repeated measures?
Reduces individual differences as P is being compared to themselves and uses fewer P’s so maybe more cost and time effective
What are the disadvantages of repeated measures?
Must be counterbalanced due to order effects and P’s may work out the IV and display DC’s
What are advantages of independent measures?
Unaffected by order effects as each P is only tested once, less likely to be affected by DC’s and less time consuming than matched groups
What are the disadvantages of independent measures?
Individual differences may skew the results and findings, large sample needed to be sure the DV is caused by IV and not by individual differences
What are the advantages of matched groups?
Unaffected by order effects or DC’s, controls P variables better because P’s are matched on variables important to the study
What are the disadvantages of matched groups?
Very time consuming to match P’s, impossible to match P’s on enough variables to be sure that there are no possible extraneous variables or individual differences
Define self selecting sampling method
This is when people volunteer to take part in the study. Often adverts, posters or leaflets will be distributed which contain details about the research
Define opportunity sampling method
A sample of P’s produced by selecting those who are most readily available at a given time and place selected by the researcher
Define random sampling method
A technique in which each member of the target population has an equal chance of being selected (e.g. using a random name generator)
Define snowball sampling
When P’s are asked to contact their friends and family and ask them to also take part in the research
What are the strengths of self selecting?
Can target certain groups you want
Relatively easy and P’s are likely to turn up
What are the weaknesses of self selecting?
Biased based on who volunteers (more confident people?) and possible time and cost of the advertising process
What are the strengths of opportunity sampling?
Quick to gather P’s and very easy as no advertising or selection process required
What are weaknesses of opportunity sampling?
Biased based on where you go and who is available at the time
May be less ethical as P’s may feel more obliged to take part
What are strengths of random sampling?
Should be representative of the target population and all have chance of being selected
What are weaknesses of random sampling?
Can be difficult to ensure all names from target pop are included
Can still be biased on who (from those selected) are willing to take part
What are strengths of snowball sampling?
Easy as only requires finding a few P’s before they recruit the rest
Relatively cheap
Good when after ‘rare’ groups
What are weaknesses of snowball sampling?
Biased as all P’s know each other and are likely to have many similarities
May not get enough P’s
What is quantitative data?
Quantities of things (e.g. raw scores, numbers and percentages)
What is qualitative data?
Qualities of things (e.g. descriptions, words, meanings, pictures)
What are the strengths of quantitative data?
Easy comparisons
Summarises easily into percentages
Reliable and replicable
What are the weaknesses of quantitative data?
Not reflective of everyday life
EV us lacking
No insight into why results occurred
What are the strengths of qualitative data?
Richness and details to the findings
Higher levels of validity
What are the weaknesses of qualitative data?
Harder to summarise
Difficult to make comparisons
Define ‘measures of central tendency’
These all aim to express the ‘average’ or ‘typical’ score within a data set
What are the 3 measures of central tendency?
Mean, median and mode
What are the advantages and disadvantages of the mean?
+: Accounts for all of the results obtained
-: Allows for extreme results and can be skewed or distorted
What are the advantages and disadvantages of the median?
+: Eliminates extreme scores
-: Could be a result that doesn’t exist
What are the advantages and disadvantages of the mode?
+: Represents the majority of results and works for non-numerical data
-: Doesn’t consider all values
Define ‘measures of dispersion’
They indicate how far the results are spread out around the ‘typical’ score
What are the 3 measures of dispersion?
Range
Variance
Standard deviation
How is the variance calculated?
Subtract each score from the mean score (this is ‘d’)
Square each ‘d’ score
Find the mean of the ‘d’ squared’s
What are the advantages and disadvantages of the range?
+: Shows us the range of values in the data
-: Can be skewed by extreme values and doesn’t account for the distribution of data