additional research methods and techniques Flashcards
what is a twin study?
a study where a trait/behaviour is compared between twins to see how similar they are
concordance rate - the degree to which two people are similar on a particular trait/behaviour
what does concordance rate suggest?
twin studies
if trait/beh is entirely genetic, then MZ twins would show 100% concordance
if a trait/beh is influenced more by genes than environment, then we would expect MZ twins to show a higher concordance rate than DZ twins
twin studies - strengths
Allows researchers to measure the influence of genes because each set of twins share an environment, so the only difference between MZ and DZ twins is genetics (MZ-100, DZ-50). Therefore the infuence of nature vs nurture can be measured
Samples usually large because data is taken from twin databases whcih contan info on many variables (mental health, addiction). Therefore samples can be representative due to being large
twin studies - weaknesses
Twin studies assume twins grow up in the same environemnt, but this is wrong because there are small diferences between even identical twins, e.g. one twin may be sportier than the other. Thesse differences mean there are actually TWO environmental influences: shared and nonshared
Twin studies can’t identify the specific genes involved, just a broad indication of whether a behaviour is genetic or environmental. Therefore they are a good starting point but studies which use more scientific methods are needed to identify individual genes
what are adoption studies
Compare the concordance rate of an adoptee with their biological and adoptive parents
How do adoption studies suggest a behaviour is genetic?
The adoptee has a high concordance rate with their biological parents but not their adoptive
How do adoption studies suggest a behaviour is environmental?
The adoptee has a high concordance rate with their adoptive parents but not their biological
adoption studies - strengths
Adoption studies control the influence of environment so differences between sets of adoptees can be said to be genetic.
Therefore the influence of nature vs nurture can be measured
Useful to show the environment may play a greater role than twin studies suggest. Thus adoption studies should be used in addition to twin studies to ensure overestimations aren’t made.
adoption studies - weaknesses
Adoptive studies may lack validity because of ‘selective placement’ (children adopted to families similar to their biological families)
Therefore some of the similarities with biological relatives is actually due to environmental similarities rather than genes
Adoption studies have limited generalisability. Therefore conclusions about the effects of genes? on ? may not be generalisable to the population as a whole.
what are case studies?
case studies are in-depth investigtions of a single person, group or event
use a wide range of methods and can gather both qualitative and quantitative data
strengths of case studies
large amounts of in-depth data (qualitative and quantitative) can provide brilliant insight. Tests and assessments can be carried out more than once (test-re-test) to check for reliability and validity.
weaknesses of case studies
risk of inaccurate recording of data or subjective interpretation of information due to large amounts of time invested and rapport between participant and researcher meaning objectivity may be lost, lowering the validity of the results
poor populatuion validity due to unrepresentative sample of usually one or small group of pps with interesting or unusual behaviour which means the results may not be generalisable
what is content analysis
a way of observing, describing, quantifying and interpreting qualitative data
the content produced by people (TV shows, magazines, newspapers, articles, books and other forms of media) are observed and analysed
procedure of content analysis
data is collected - researcher reads through or examines the data, making themselves familiar with it - researcher identifies coding units - data is analysed by applying the coding units - tally is made of teh number of times that a coding unit appears
strengths of content analysis
weaknesses of content analysis
It requires interpretation of data, quite often words may be hard to ‘fit’ into a category. This reduces the scientific status of the method as results are likely to be subjective, lowering validity
Turning qualitative data into quantitative may mean that detail and context is lost, reducing the validity of the results
what are longitudinal studies?
strengths of longitudinal studies
weaknesses of longitudinal studies
what are cross-sectional studies?
takes measurements of one group of pps at a specific time and comapres it with another group
provides snapshot of the difference between groups
strengths of cross-sectional studies
practical issue - not as time consuming as longitudinal design - the data is analysed and compared more rapidly. this is useful if results are being used to affect government policy
generalisability - pps are less likely to drop out as it will be a shorter amount of time to commit too than compared to longitudinal research, resulting in more representative samples
weaknesses of cross-sectional studies
validity - individual differences is a major drawback and likely to affect conclusions which are drawn on making comparisons between groups of different people in each age group
cohort effects - the differences between groups could be attributed to the effects of being raised in a particular time and/or place e.g. different generations are affected by technology/war/changes to laws etc.
what are cross-cultural studies?
involves taking samples from different cultural groups to draw comparisons about the similarities and differences between them to consider how culture may impact on the behaviour in question
strengths of cross-cultural studies
reliability - likely to be replicable as procedures are standardised and controlled so that they can be replicated in different cultures
validity - if the procedure is replicable then the only variable which is changing is culture therefore accurate cause and effect conclusions about the extent to which nature and nurture play a role in people’s experiences can be made
weaknesses of cross-cultural studies
cultural bias - using a standardised procedure which has been developed in one culture may be biased towards that culture (ethnocentric) and may lose consistency if translated
generalisability - pps used in a cross-cultural study won’t necessarily represent teh culture accurately (pop validity), therefore the results may not be generalisable to the whole culture
compare cross-sectional and longitudinal
similarities
- both allow changes in behaviour over time to be measured and cause and effect conclusions drawn
differences
- long. measures same pps at serveral points over time whereas cross-sectional measures diff groups of people at each age
- long. doesn’t have problems with pps variables as its the same group of pps, whereas cross-sectional does due to diff pps
- long = higher drop out rate (attrition) due to long term commitment, whereas cross-sectional has lower drop out
what is a meta-analysis?
Looking at secondary data from multiple studies conducted by other researchers and drawing findings together to make overall conclusions
strengths fo meta-analysis
weaknesses of meta-analysis
what is a pilot study
A pilot study is a small-scale version of an investigation which is done before the real investigation is taken
* They are carried out to allow potential problems of the study to be identified and the procedure to be modified to deal with these
- This allows money and time to be saved in the long run
