Representation of Data

• What diagram is this?

  Cumulative frequency

  
• What else can you draw once you have a cumulative frequency diagram?

  box plot
• What diagram is this?

  box plot

  
• How has the box plot been calculated from this cumulative frequency diagram?

  Marking the quartiles at the appropriate height

  
• Label the box plot:

  A) min

  B) q1

  C) Q2

  D) Q3

  E) max

  F) outlier

  
• Standard way of finding an outlier above $Q_3$ :

  
  

  $Q_3\ +$$\ 1.5\ \times IQR$
• What diagram is this?

  histogram

  
• What data is a histogram appropriate for?

  continuous

  no gaps
• To find the frequency density of a histogram you do:

  $\frac{frequency}{class\ width}$
• To find the area of a histogram:

  $frequency\ \times k$ (k is typically provided in the question)
• When comparing two histograms, you want to mention:

  1. location of peaks
  2. spread of data
  3. context and what the spread means