Chapter 2

• Unexplained Underperformance Syndrome (UPS)
• Psychology began with:

  • the deliberate attempt to start a new science
  • applying the method of the natural sciences to some of the questions of philosophy
• Hypothesis - a clear predictive statement which is an attempt to explain the observations
• Meta-Analysis:

  • combines the results of many studies as if they were all one huge study
  • determines which variations in procedure increase or decrease the effects
• Theory - an explanation or model that fits many observations and makes accurate predictions
• Well-Formed Theories are falsifiable


  Falsifiable - states in such clear precise terms that we can see what evidence would count aginst it. The theory is solid; it provides everything that makes it true and anything that could make it false
• Good Theories:

  • start with as few assumptions as possible
  • lead to many correct predictions
• Burden of Proof - the obligation to present evidence to support one's claim
• Parsimony:

  • stick with ideas that work and try hard to avoid new assumptions
  • adhere to what we already believe to resist radically new hypotheses


  Don't try to do anything that is unprovable
• Operational Definition - specifies the operations or procedures used to produce or measure something
• Convenience Sample - a group chosen because of its ease of study
• Representative Sample - one that resembles the population
• Random Sample - one in which every individual in the population has an equal chance of being selected
• Cross-Cultural Sample - groups of people from at least two cultures
• Ways to gather samples from research

  cross-cultural sample, random sample, convenience sample, representative sample
• Correlation - a measure of the relationship between two variables


  Outlier - does not match the majority of the sample or the correlation
• Experiments - studies in which investigators manipulate at least one variable while measuring at least one other variable


  Independent Variable - the factor the researcher changes or controls

  Dependent Variable - the factor that changes in response to the independent variable
• • Experimental Group - the group that receives the treatment
  • Control Group - the group that receives the placebo
  • Random Assignment - experimenter does not indicate who is assigned to which group
  • Experimental Bias - the tendency for the experimenter to misperceive the results to favor their hypothesis
  • Single-Blind Study - participants don't know which group they are in
  • Double-Blind Study - participants and researchers/observers don't know which group they are in