Planning research and methodological issues

• What are the different sampling methods

  • Random sampling
  • snowball sampling
  • self selected/volunteer sampling
  • opportunity sampling
• what is random sampling


  Every person in each target population has an equal chance of being selected by using a computer generator
• Strengths and weaknesses of random sampling

  Advantage

  equal chance, unbiased and most representative

  
  

  disadvantage: takes much more time and effort and may be impossible depending on target population. Also costly and time consuming
• What is self selected/volunteer sampling

  People put themselves forward e.g. by seeing an advertisement, poster, newspaper
• Strengths and weaknesses of self selected/ volunteer sampling

  Advantage

  participants select themselves so they’re easy to obtain and less likely to withdraw, they also specify the exact criteria

  disadvantage

  selectivity of responses (most of the target population unlikely to respond. Not random

  biased response, most likely from extroverts/confident people. unrepresentative
• What is opportunity sampling

  Using people who are freely and readily available around you e.g. on the streets
• Strengths and weaknesses of opportunity sampling

  Advantage

  quickest and easiest as anyone willing to take part is selected. Convenient and less time consuming

  disadvantage

  inevitably biased as sample is drawn from a small part of the target population. Unrepresentative, restricted and makes generalisations
• What is snowball sampling

  (Used if target population is very specific/difficult to recruit) asking someone who fits the criteria to ask people they know (friends/family) if they fit the criteria
• Advantages and disadvantages of snowball sampling

  Advantage

  representative ( allows you to gather people you wouldn’t otherwise have access to)

  disadvantage

  restricted/unrepresentative as participants likely come from one area. Not generalisable
• Validity= accuracy
• What are the types of external validity?

  • Ecological validity
  • population validity
• What are the types of internal validity?

  • Face
  • concurrent
  • criterion
  • construct
• definitions of external validity

  • Ecological: refers to our environment, natural habitat or behaviour (will the measure used be able to reflect real life behaviour?)
  • Population: does the sample used reflect the wider target population?
• Reliability= consistency
• What are the four ethical principles

  • Respect
  • competence
  • responsibility
  • integrity
• Respect (ethical principles)

  • Informed consent: investigator should inform all participants of the objectives when possible. Research with children (or those with impairments) requires consent from parents.
  • right to withdraw: investigators should remind participants they can withdraw anytime before, during or after a study.
  • confidentiality: participants to remain anonymous
• Competence (ethical principles)

  • Justification of actions: psychologists should continue with the development and maintaining high levels of competence in their research. Accept ethical dilemmas (which inevitably arise) and accept responsibility by resolving such dilemmas
• Responsibility (ethical principles)

  • Protection from harm: investigators have a responsibility to protect participants from physical and psychological harm. They must be protected form stress. Assurance should be given that answers to personal questions need not to be given.
  • Debriefing: to restore participants mental state to how it was before the study (does not provide a justification for unethical aspects of any investigation)
• Integrity (ethical principles)

  • deception: the withholding of information/misleading of participants is unacceptable (without extremely strong scientific or medical justification) if they‘re likely to object or show unease once debriefed.
  • observational research: unless consent is given, observational research is only acceptable in situations where those observed could expect to be observed by strangers
• Why are ethical issues important

  • The aim of psychology is to increase our understanding of human behaviour in order to help people
  • Ethical issues raised by many studies has damaged the image of psychology (could result in running out of participants for studies)
• Brief explanations of code of ethics and conduct 


  • Respect: informed consent, confidentiality, right to withdraw
  • competence: includes awareness of professional ethics making ethical decisions
  • responsibility: protection from harm and debriefing
  • integrity: honesty (avoiding deception) and addressing misconduct
• Ethnocentrism 


  One may see their own culture as the correct way of living.
• Sampling bias


  How representative the sample is to the target population. Can results be accurately generalised to another group
• Falsifiability 


  The ability for a theory to be proven true or false
• induction

  When research starts with observations and builds a theory based on these observations
• Operationalisation 


  The process of defining and making variables measurable
• Standardisation


  when procedures in research are kept the same
• Objectivity 


  conducting research with an open mind and considering facts rather than personal feelings
• hypothesis 


  An idea that can be tested to see if it might be true
• Deduction


  When research starts with a theory and seeks evidence for the theory
• Conclusion 


  A final decision, judgement or statement about what the results from a study may tell us about behaviour
• Theory 


  An explanation for observations from research
• Variables 


  things that are changed or measured in a piece of research.
• What are ways of dealing with ethical issues?

  • Debriefing
  • Ethics committee
  • Presumptive consent
• What is debriefing?


  a way of dealing with ethical issues

  • Participants have the right to refuse permission for the researcher to use their data. Aims to restore P’s to the mental state they were in before the study
• What is ethics committee?


  a way of dealing with ethical issues

  • A group of people who approve a study before it begins, they look at how the researcher plans to deal with ethical issues
• What is presumptive consent?


  a way of dealing with ethical issues

  • Dealing with lack of informed consent or deception by asking a group of similar people to the participants. If they agree to take part, it’s presumed the real P’s do as well
• What are ways to test internal reliability?


  split half method: do all parts of the measure contribute equally to what is being measured? (e.g. does each half of a test share the same level of difficulty?)
• What are ways to test external reliability?


  .

  • Test re-test: measures stability over time e.g. participants doing the same test at different times
  • Inter-rater: does the rating of one observer correlate with another watching the same behaviour? e.g. the ability of 2 researchers to share the same finding
• What are the types of reliability?


  internal and external