PSYCHOLOGY1 research methods

• Define target population


  group of people who researcher is interested in studying
• Define sample


  group of people who take part in an experiment. this is selected from people from the target population
• Define hypothesis


  A clear, precise, testable statement that states the relationship between the variables to be investigated.
• Define variable


  A factor that can change in an experiment
• define directional


  states the direction of the difference or relationships
• define non directional


  does not state the difference
• Define alternative hypothesis


  states that there is a relationship between variables
• define independant variable


  what you change/ manipulate
• define dependant variable


  the effect of the change
• define aim


  a general statement on what you hope to find out
• define a null hypothesis

  a statement of no relationship between variables/ no difference
• define extraneous variable


  unwanted factors that affect the relationship between dv and iv and distorts the results
• define random allocation


  putting the participants into the conditions of the experiment using random methods (have same chance of being in one group as the other)
• what EV does random allocation control

  participant variables
• Define counter balancing


  this is when half the participants complete condition A first then condition B, whereas other half does B first then A
• what EV does counter-balancing control


  order effects
• define randomisation


  using chance (such as tossing a coin) to determine the order of a procedure (eg word order in a list)
• what EV does randomisation control

  investigator effects
• define demand characteristics


  any cue from the researcher or experimental situation that reveals the purpose of the investigation to the participant and could lead to them guessing the aim and changing behaviour
• define participant variables


  the difference between the participants in the study eg age, personality
• define situational variables


  features of the experimental situation that could affect the IIV eg temp, time, noise
• define investigator effects


  When a researcher unintentionally gives clues to participants, altering their behaviour.
• Define order effects


  an extraneous variable that arises from the order in which conditions are presented
• define standardized procedure


  a set order of carrying out a study that is applied to all participants
• define instructions


  the written or verbal information given to participants during the experiment
• define experimental design


  the different ways in which participants can be organised in relation to the conditions of an experiment . there are 3 types of experimental designs
• define general population


  all of the people in the world
• define independent groups


  when there are separate groups of people for each level of the independent variable in the experiment
• define repeated measures


  all the participants receive all levels of the IV
• define matched pairs


  Participants paired on a variable and then one of each pair allocated to each experimental condition
• define random sampling


  every person in the target population has an equal chance of being selected
• example of random sampling

  pulling names out of a hat
• strength of random sampling

  no researcher bias
• weakness of random sampling

  time consuming and much effort
• define opportunity sampling


  the researcher approaches people who are available at the time and fit the criteria and ask them to participate
• example of opportunity sampling


  ask people close to you to participate
• strength of opportunity sampling


  quick and easy
• weakness of opportunity sampling

  unrepresentative and likely to be biased
• define systematic sampling


  every nth person in the population is chosen as part of the sample.
• example of systematic sampling

  eg, every 5th person