DataAnalysis inWF ED
18 September 2015
1. Each variable
must have its
own column:
1. Each variable
must have its
own column:
2. Each
observation must
have its own row:
1. Each variable
must have its
own column:
2. Each
observation must
have its own row:
3. Each value
must have its
own cell:
UNTIDY
UNTIDY TIDY
 YES, for understanding (transformation,
visualization, and modeling)
 YES, for understanding (transformation,
visualization, and modeling)
 NO, for communication
An entity that has two or more mutually
exclusive values
An entity that has two or more mutually
exclusive values
An entity that has two or more mutually
exclusive values
An entity that has two or more mutually
exclusive values
Some examples?
Measurement is a process of assigning values
to variables based on rules
Type Level Example
Nominal Unordered categories Gender is either male or
female
Ordinal Ordered
categories
Size is small, medium or, large
Interval No true zero, but equal
intervals
% items correct on
achievement test as a
measure of ability
Ratio True zero and equal intervals % items correct on
achievement test
DataAnalysis inWF ED
18 September 2015
http://economywork.com/courses/data/dataSYL/quiz4.html
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WF ED 540, Data Analysis, Fall 2017