Graphing

Read these sections and complete the questions at the end of each section. First, we'll look at the available methods to portray distributions of quantitative variables. Then, we'll introduce the stem and leaf plot and how to capture the frequency of your data. We'll also discuss box plots for the purpose of identifying outliers and for comparing distributions and bar charts for quantitative variables. Finally, we'll talk about line graphs, which are based on bar graphs.

Frequency Polygons

Answers

  1. histogram
    Frequency polygons do not list the raw data, as stem and leaf plots do. Frequency polygons are very similar to histograms, except histograms have bars and frequency polygons have dots and lines connecting the frequencies of each class interval.

  2. comparing distributions
    Frequency polygons are better at comparing distributions because two frequency polygons can be displayed in the same graph without obscuring each other. Both histograms and frequency polygons show the shape of the distribution. Neither necessarily reveals the exact values in a distribution.

  3. large target
    Almost all of the times for the large target are below 750 msec., whereas there are many longer times for the small target.