Graphs

• Box and Whisker plots include outliers.

  outliers:

  lower = Q1 - (1.5 x IQR)

  upper = Q3 - (1.5 x IQR)
• box plot include: median, quartiles, interquartile range, outliers, maximum and minimum values
• cumulative frequency graphs:

  • if you are given grouped data because you cannot find exact values.
  • finds estimates for: median, quartiles, percentiles
  • to find percentiles, use normal formula for percentages
• histogram:

  • grouped continuous data
  • area of bar = frequency
  • allows to see general spread
• when comparing data: SIGNIFICANTLY
• bivariate data = data that has two variables
• correlation:

  • linear corelation only
  • strong, weak or no/zero
• frequency density = frequency / class width (inequality)