Chapter 4-Displaying and Summarizing Quantitative Data

Chapter 4-Displaying and Summarizing Quantitative Data

1. Display or picture

   • Histogram
     • Each bar represents the frequency (or relative frequency) of values falling in each bin.
   • Steam and leaf
     • A stem-and-leaf display shows quantitative data values in a way that sketches the distribution of the data
   • Dotplot
     • a dot for each case against a single axis

2. Numerically= Measure of dispersion

   • Mean
   • Standard
   • IQR

3. Shape

   • Center
     • Measures of center include the mean and median.
   • Unimodal/bimodal
     • One mode/two modes
   • Uniform
     • roughly flat
   • Symmetric
     • if the two halves on either side of the center look approximately like mirror images of each other