Soft drink example follow up 2 pie charts useful with

 SOFT DRINK EXAMPLE FOLLOW UP
2. Pie Charts
 Useful with relative frequency and percent frequency only . MUST
SHOW PARTS OF A WHOLE!
 Often misused in practice.
 Correct:
27%
22%
21%
21%
1%
8%
Impact of Technology on Golf
Golf Ball
Club head
material
Shaft material
Club head size
Shaft length
Don't know

OIS 2340 – Business Statistics Chapters 1 & 2
5
 Incorrect:
 SOFT DRINK EXAMPLE FOLLOW UP.
Summarizing QUANTITATIVE Data
Tabular Summaries
1. Frequency Distribution
 Classes must be mutually exclusive (nonoverlapping).
 Classes must be all-inclusive
 Classes should be equal width (if possible).
 There should be no empty classes (if possible).
Creation
a) Determine the number of classes (bins) you will need.
.
Rule of Thumb…Between 5 and 20 Classes
b) Determine the width of each class (bin).
c) Determine the class (bin) boundaries.
d) Determine the frequency for each class (bin).
 AUDIT TIMES EXAMPLE
\
$5,410
$5,900
$6,320
$7,143
Funding Per Student
Lewis and Clark
College
Boise State
University
Idaho State
University
University of Idaho

OIS 2340 – Business Statistics Chapters 1 & 2
6
2. Relative Frequency and Percent Frequency Distributions
 Shows the proportion or percentage of items in each of several categories or
classes.
 Relative Frequency = Frequency of a Class ÷ n , where n is the number of
observations.
 Percent Frequency = Relative Frequency x 100.
 Useful for comparing similar sets of data with different sample sizes.
 AUDIT TIMES FOLLOW UP
3. Cumulative Frequency Distribution
 Uses the same classes as a Frequency or Percent Frequency Distribution.
 Shows the number of data points with values less than or equal to the upper
class limit of each class.
 AUDIT TIMES FOLLOW UP
4. Cumulative Relative Frequency and Cumulative Percent Frequency Distributions
 Used same as Cumulative Frequency, but using the ratio or percent
frequencies instead.