Psychology

• Random Sampling: A sample where every member of the population has an equal chance of being selected for the study.
• Experimental


  scientific study of behaviours, motives, or cognition in a laboratory or other controlled setting
• operational definition


  a statement of the procedures or ways in which a researcher is going to measure a specific variable or behaviour in a study
• single-blind study


  a type of experiment or clinical trial in which the experimenters are aware of which subjects are receiving the treatment or independent variable, but the participants of the study are not
• qualitative research


  a method of research that produces descriptive (non numerical) data
• sample error


  differences between what is present in a population and what is present in a sample
• case study

  an in-depth study of a particular individual
• stratified sample 


  a method is sampling that involves dividing a population into subgroups or strata and then randomly selecting individuals from each group for study
• naturalistic observation 


  observing subjects in their natural environment
• random sample 


  selecting individuals for a study by selecting them from a larger potential group
• double-blind study 


  neither the participants nor the experimenters know who is receiving a particular treatment
• sample

  a representative subset of a population which is being studied
• control group separated from the rest of the experiment
• external validity


  the extent to which the results of a study can be generalized or applied to settings, people, times, and measures other than the ones used in the study
• hypothesis


  a testable statement of what researchers expect to happen in a study and why
• internal validity

  casual relationship exists between the independent and the dependent variables
• placebo effect 


  beneficial effect that happens due to the persons belief that they'll receive a benefit
• quantitative research


  a method of research that relies on measuring using a numerical system
• independent variable 


  the variable the experimenter manipulates or changes and is assumed to directly affect the dependent variable
• self-fulfilling prophecy 


  a belief or expectation about onself
• confounding variable

  extraneous factor that intervenes with the relationship between an experiments independent and dependent variables
• longitudinal study 


  type of observational and relational study that involves monitoring a population over an extended period of time
• cross-sectional study 


  a type of observational study that involves analyzing information about a population at a specific point in time
• research question


  main focus of a research project
• dependent variable 


  is a measure of a certain aspect of a participants behaviour that varies in response to change in another variable