# Techniques for Summarizing Quantitative Data

Topics: Harshad number, Statistical charts and diagrams, 10 Pages: 2 (290 words) Published: October 31, 2012
Techniques for Summarizing
Quantitative Data
frequency histogram
A sample of 40 female statistics students were
asked how many times they cried in the previous
month.Their replies were as follows:

Stem-Leaf Plot
A natural way to organize (group) quantitative data is with the order property of the real numbers, i.e., arrange the data from least to greatest. For example, the 30 weights: 185, 160, 235, 165, 125, 175, 185, 132, 168, 112, 170, 155, 105, 158, 120, 190, 140, 185, 125, 180, 145, 110, 155 135, 170, 113, 155, 175, 145, 130 are more easily comprehended in order: 105, 110, 112, 113, 120, 125, 125, 130, 132, 135, 140, 145, 145, 155, 155, 155, 158, 160, 165, 168, 170, 170, 175, 175, 180, 185, 185, 185, 190, 235. Note that each weight has been listed as many times as it occurs. This information can be visually presented with a stem and leaf plot. A position has been chosen to break the numbers into a stem and a leaf. The leaf will always be one digit. The stems are listed on the left, and the corresponding leaves (if any) on the right. Visually a stem-and leaf plot looks like a bar chart; the categories are defined by the decimal structure of the numbers. A stem-and leaf plot for the above data is presented below:

10 | 5
11 | 023
12 | 055
13 | 025
14 | 055
15 | 5558
16 | 058
17 | 0055
18 | 0555
19 | 0
20 |
21 |
22 |
23 | 5

Techniques for Summarizing
Categorical Data
Frequency Table
A frequency table shows the number of occurrences of each category.

Pareto Chart
A bar chart with categories arranged from
the highest to the lowest is called a Pareto Chart.