research methods

• experimental group

  exposed to the independent variable

  exposed to experimental conditions
• control group 


  group not exposed to the independent variable
• correlation studies

  is used to investigate the relationship that exists between variables without any control over the setting in which the relationship occurs or any manipulation by the researcher

  done by applying a statistical technique that have been collected on each variable

  correlation studies are used in psychology when an experiment is inappropriate and impractical

  involve behavioral variables
• advantages of correlation studies

  1. discover the relationship between variables
  2. can be conducted outside an artificial laboratory (results are more realistic)
  3. can indicate patterns or trends
• disadvantages of correlational studies

  1. cannot draw cause and effect relationships
  2. difficult to control unwanted variables
• observational study

  involves a collection of data by carefully watching and recording behavior as it occurs without any intervention or manipulation.

  the method to collect data is highly detailed (specific scientific investigation)
• data collected in an observational study

  1. structured - prepared system (checklist)
  2. unstructured - no format
  3. semi-structured - predetermined format

  most studies used are structured and use systematic data collection in controlled settings such as a checklist with predetermined criteria
• advantage of observational study

  1. no manipulation is needed from the experimenter
  2. structured observations are accurate, therefore data obtained is accurate
  3. some types of human behavior can only be studied as they naturally occur, as it would be unethical to manipulate them in a laboratory setting.
• disadvantages of observational data

  1. cannot be used to determine the causes of behaviour of interest.
  2. potential observer bias (they see what they want to see)
  3. the participant variables (socioeconomic background, sex, age) may be biased and therefore cannot be generalised to the entire population.
• case studies

  an intensive, in-depth investigation of the behavior, activity event, or problem in the interest, of an individual group or organization.

  in-depth
• ways to collect data (case study)

  • interveiw
  • medical records
  • school reports
  • psychological testing
  • observations
• advantages of case studies

  1. useful way of obtaining detailed information on behaviour and mental processes. the data is rich and in-depth
  2. avoid artificiality that can be present in laboratory experiments
  3. conducted over a prolonged period of time (longitudinal)
• disadvantages of case studies

  1. cannot test or establish a cause-effect relationship
  2. small sample size cannot be generalised to an entire population
  3. time consuming
• longitudinal studies

  long-term investigation that follows the same group of people over an extended period of time.

  it records behaviors, thoughts, and feelings that may have changed over time
• cross-sectional studies

  selects and compares a group of participants of different ages over a short period of time.
• advantages of cross-sectional studies

  1. inexpensive
  2. quick
  3. researchers can compare different variables at the same time
• disadvantages of cross-sectional studies

  1. differences can be found between age groups
  2. generational influence cannot be controlled
• advantage of longitudinal studies

  1. useful way of examining consistencies
  2. useful way of examining inconsistencies
  3. can study early and late development
• the disadvantage of longitudinal studies

  1. expensive
  2. time-consuming
  3. hard to keep in touch with same group over a long period of time
• extraneous variable

  is a variable other than the iv that may cause a change in the dv and therefore may affect the results
• confounding variable

  is a variable other then the iv that had an effect on the dv which cannot be separated from that of the iv.

  it has an effect
• demand characteristics

  when people know they are in the experiment they may act in a way they think the experimenter wants them to

  cues in the experiment that may influence or bias a participant's results
• ways to control demand characteristics

  1. withhold information
  2. single-blind procedures
  3. placebo
  4. double-blind procedures
  5. standardised instructions and procedures
• experimenter effect

  personal characteristics of the experimenter and their behavior during the experiment may affect how participants respond.

  the influence the experimenter may have on the results of their investigation. this could occur from

  • interaction with participants
  • unintentional errors
• personal characteristics that could affect results

  • sex
  • ethnic background
  • attitudes
  • expectations
• experimenter expectancy

  cues the experimenter provides unintentionally

  • body language
  • facial expressions
  • tone of voice
• double-blind procedures

  when neither the particpants nor the experimenter knows the particular experiment conditions
• types of extraneous variables

  • environmental
  • situational
  • demand
  • placebo
  • participant variables
  • experimenter effect
• ways to control extraneous variables

  • similar in personal characteristics
  • random sampling
  • appropriate experimental design
• environmental variables (situational variables )

  external factors associated with the experimental setting that may influence participant responses and therefore results

  procedures not only involve what the experimenter doe but also how the relevant research activities are conducted.
• standardisation

  non standardised= not the same

  even small variations in instructions and procedures may affect participant responses.

  if the experimenter doesn't standardise their procedure they aren't controlling all of the possible extraneous and confounding variables that could influence the dv
• ways to control standardization

  hold all situational variables constant