RESEARCH PART 1

• population

  group of people who are the focus of the researcher's interest
• sample

  a group of people who take part in a research investigation
• sampling technique

  method used to select people from the population
• bias

  some groups may over or under represented - limiting generalisations
• generalisations

  findings and conclusions from an investigation can be made to the target population
• experiment

  aim, participants, method, how, findings, conclusions, evaluation, limitations
• validity

  accuracy
• ecological 


  everyday life
• quasi experiments

  study that lacks key ingredients (no IV)
• experimental methods

  method with a manipulation of the IV, where researcher measures effects on DV
• Independent variable

  changing variable
• dependent variable

  measuring
• lab experiments

  conducted in highly controlled environment
• field experiments

  takes place in a natural setting
• natural experiments

  change in IV would have happened without the researcher
• random sampling

  every member of the population have an EQUAL selection chance
• how - random sampling

  sampling frame obtained - names drawn randomly
• random sampling - strength

  unbiased - all members have equal chance of selection
• ramdom sampling - limitation

  not representative - ratio of males and females may not reflect population
• systematic sampling

  every nth number is selected
• how - systematic sampling 


  list of names / size of sample = nth number
• strength - systematic sampling 


  useful for large population - simpler to conduct
• limitation - systematic sampling 


  not every member of population have an equal chance of being selected
• stratified sampling

  composition of sample reflects proportions of people in each strata
• how - stratified sampling

  researcher make strata and proportions , then pps that make the strata are chosen randomly
• strength - stratified sampling

  representative sample - designed to reflect composition of population
• limitation - stratified sampling

  cannot reflect all the ways people are different
• opportunity sampling

  consists of people available to the researcher at the time
• how - opportunity sampling

  researcher asks people if they can participate at the time it's conducted
• strength - opportunity sampling


  first participants found are used - quicker
• limitation - opportunity sampling

  drawn from small population - not every member has an equal chance, not generalised
• volunteer sampling

  consists of people who volunteer to take part
• volunteer sampling - how

  advertisement put up in a place seen by target population
• volunteer sampling - strength

  participants selected themselves so less likely to drop out
• volunteer sampling - limitation

  volunteers may by more motivated, makes it bias and not generalised
• difference question....


  WHEREAS
• hypothesis

  statement made at the start which states the relationship between variable
• directional hypothesis

  clear direction between conditions (more,less,higher,lower)
• non-directional hypothesis

  states a difference between conditions - no direction
• aim

  general statement of what the researcher intends to investigate