Z scores

  • Z-score: way to provide an exact location for a score within a distribution
    • tells area under curve
    • sign of score tells if above or below the mean
    • z-score = 0: at the mean
    • numerical value of z-score = how many standard deviations away from the mean
  • can transfer graphs to z to make standard deviations
    • extremes are past -2 and 2
  • z scores also help determine if a score is representative of a population
  • can also use z scores to standardize scores
  • probability
    • proportion that describes the frequency of the occurrence of an outcome
    • desired outcome compared to all possible outcomes
    • normal distribution