DATA SCIENCE
MIS0855 | Spring 2016
A Brief Introduction to Data
SungYong Um
sungyong.um@temple.edu
Today’s Goal
1. Learn the basic concept of metadata
2. Example
Adapted from http://www.systems-thinking.org/dikw/dikw.htm
Statistical
Analysis
Data
Information
Observation,
relationship (limiting boundary),
prediction
Adapted from http://www.systems-thinking.org/dikw/dikw.htm
Knowledge
Hypothesis
Data, Information, Knowledge
Data
Information
Knowledge
Raw, unorganized facts
Data that is processed to be useful
Application of data and information
Adapted from http://www.systems-thinking.org/dikw/dikw.htm
How does the data collected by the NSA differ from
the data collected by Ashley Madison’s site?
Adapted from http://www.systems-thinking.org/dikw/dikw.htm
Adapted from http://www.systems-thinking.org/dikw/dikw.htm
Each piece of
data can be
described by…
Metadata
“data about data”
The data itself
a title
a description
a data type
a value
So what is metadata?
Metadata
• Data Dictionary
• “Data for data”
• Data that explains what this data is, what it is for, and
how it is structured
 e.g. title, description, data type
How would you describe this data?
Metadata for Philadelphia Crime Logs
Data type
a classification that determines the possible values that data can have
Type
Description
Examples
What it’s called
in Excel
What it’s called
in Tableau
Integer
Whole numbers
35, 102, -40, 0
Number
Number (whole)
Floating point
Fractional values
3.56, -1.0, 10.123
Number
Number (decimal)
Boolean
Binary (2) values
True/False,
Male/Female
N/A
Boolean
String
Numeric and nonnumeric characters
Bob, I like cheese,
hello123
Text
String
Date/Time
Calendar date and
time
8/31/2014,
10:05 AM,
8/31/2014 10:05 AM
Date
Date or
Date & time
Why do we care about data types?
Why do we need Metadata?
• Because computers are dumb!
• It is getting there, but computers are still not able to
understand what the data means and what it is for.
• So, we have to describe it for them.
http://www.manning.com/sande/excerpt_preface.html
Why do we care about metadata?
Documents what the data means
• Enables navigation
• Facilitates understanding
• Eliminates guesswork
Metadata is everywhere
Metadata in the news
What is “telephony metadata?”
IMEI/MEID, IMSI, trunk identifiers?
What can it tell you?
How does the NSA turn this
(meta)data into information?
What is the “non-metadata” data
in a telephone call?
The Ashley Madison
Data Breach
How is this data different
from other “famous” data
breaches?
In what ways is it more
damaging than telephony
metadata?
Does this change our notion
of privacy?