Graphical Analysis Questions
& Answers
Visual Depictions – ANSWERS
These are tools that make it easier for 6Sigma professionals or sponsors to retell
the story to others, which can be helpful for training, building cultural buy-in for a
process change, or even resource requests.
Graphical Analysis Tools – ANSWERS
Pareto Charts (ch. 5 & 14)
Run Charts (ch. 13)
Box Plots (ch. 14)
Introduction to Control Charts (ch. 16)
Introduction to Scatter Diagrams (ch. 14)
Bar Charts – ANSWERS
Recognizable and easy to create and read. Uses both nominal or ordinal data. Other
benefits:
1. the ability to summarize large data sets in a simple visual format
2. the ability to clarify trends
3. a well-formatted chart allows most people to easily estimate important values
4. the ability to visually check data and identify areas where data might be skewed
5. the ability to easily display data sets that range above and below zero on the same
chart
Bar Chart's Limitation – ANSWERS
Rarely on their own provides detailed data about causes or patterns in data, easy to
manipulate colors, order, and layout of a bar chart to influence the intended message
Nominal Data - ANSWERS1. Nominal is considered to be the lowest data
classification level and simply involves applying number labels to a qualitative
description so statistical analysis programs and tests can be applied to the data.
The numbers assigned to each category don't provide any information about
whether the data is better or worse than other data in the listing - in nominal data,
numbers don't reflect a scale.
2. data of categories only. Data cannot be arranged in an ordering scheme.
(Gender, Race, Religion)
Ordinal Data - ANSWERS1. A higher form of data than nominal data. The numbers
provide meaning, the numbers are qualitative in nature, but they are also ranked in an
order that makes sense
, 2. data exists in categories that are ordered but differences cannot be determined or
they are meaningless. (Example: on a scale 1 to 10, Suzy rated movie A as a 10 and
movie B as a 9, the conclusion is Suzy likes movie A better, but exactly how much more
she liked the movie is not discernible using ordinal data.)
Creating a Bar Chart on Excel – ANSWERS
Enter data within correct labels
Highlight the cells that you want to chart as well as the labels for the data/cells
Select Insert > Chart > Bar Chart
Select appropriate bar charts
Use Excel formatting tools to customize the chart title, colors, and labels
Column Chart – ANSWERS
The basic and most common bar chart, the visual columns representing each data
category rise vertically or horizontally.
3-D Bar or Column Chart – ANSWERS
Similar to the 2-d column chart, but with added visual appeal to a presentation. 3-d
charts are helpful if you are presenting a number of similar-looking charts in a row, as it
helps to differentiate between information in your presentation.
Stacked Bar Charts – ANSWERS
Lets you display the total nominal or ordinal data for each category while also breaking
that information into color coded category
ex: a category of sports also have bar charts split between win percentages of home
team vs visiting team
Creating a Stacked Bar Chart – ANSWERS
Must have ordinal or nominal data that is broken into categories
The categories must be the same for each data set so that the total sub-category
numbers equals the total of the main category.
ex: 3 bags broken into numbers of marbles, the number of marbles are broken
further down into categories of colors
Highlight the cells containing the data plus cells containing the data labels
Select Insert > Charts > Bar Charts > Stacked Bar Chart
Use Excel formatting tools to customize the chart title, colors, and labels
What does a bar chart require? – ANSWERS
Bar charts require nominal or ordinal data that is classified according to qualitative
information.
What is the downside to using a bar chart? – ANSWERS
Bar charts fail to reveal key information about trends that are not part of the specific
design of the chart and rarely provide detailed data.
What is the biggest benefit of using a bar chart? – ANSWERS