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Framework of Statistical
Information
Statistical Information
Statistics
Data
In print
Online
Aggregate
E-publications
E-tables
Databases
Microdata
Framework of Statistical
Information
Statistical Information
Statistics
Data
This
categoriesMicrodata
or
In printis a typology
Online of the
Aggregate
classes of statistical information.
Remember the
relationship
between
E-publications
E-tables
Databases
statistics and data, however, is causal.
Statistics are created from data.
An overlap occurs in
this chart between
Statistics: Databases
and Data: Aggregate,
which will be
discussed below.
Framework of Statistical
Information
Statistical Information
Statistics
Data
In print
Online
Aggregate
E-publications
E-tables
Databases
Microdata
Framework of Statistical
Information
Statistical Information
Statistics
Data
In print
Online
Aggregate
E-publications
E-tables
Databases
Microdata
Framework of Statistical
Information
Statistical Information
Statistics
In print
Data
Online
Aggregate
In print
E-publications
E-tables
Databases
Microdata
In Print
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Rely on yearbooks, statistical abstracts,
catalogues, and indexes to locate statistics in
print.
Examples of online indexes to print resources:
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Statistical Universe (U.S., international, government and private)
Tablebase
Example of online catalogues that include print
resources:
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U.S. Census Bureau Sales Catalog
Statistics Canada’s Online Catalogue
Framework of Statistical
Information
Statistical Information
Statistics
Data
In print
Online
Aggregate
E-publications
E-tables
Databases
Online
Microdata
Online Statistics
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Example of e-publications
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Example of e-tables
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Statistical Abstract of the United States
Statistics Canada Downloadable Publications (DSP)
Tables [and publications] containing U.S. Consumer Price
Indexes
Canadian Statistics (STC Website)
Example of statistical databases
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American Fact Finder and Data Ferrett
CANSIM II (STC Website, E-STAT, CHASS)
E-Publications
Tend to be available in PDF format
 Can use the “Select Text” Tool in the
Adobe Reader and copy columns to
another application

Statistical Information
E-Tables
Tend to be displayed in HTML
 May provide a pull-down list to view
other categories in the table
 Some e-tables will provide an alternate
format for the table that can be
downloaded (e.g., the Canadian Census
tables are available in commaseparated ASCII, IVT, and print-friendly
formats)

Databases
Often use HTML forms to define the
statistics to be retrieved
 May offer a variety of output formats for
the retrieved statistics (e.g., E-STAT
provides IVT format for Beyond 20/20,
graphs, charts, maps, and ASCII
formats for spreadsheets and
databases)

Framework of Statistical
Information
Statistical Information
Statistics
Data
In print
Online
E-publications
E-tables
Aggregate
Microdata
Aggregate
Databases
Data
Aggregate Data
Aggregate data consist of statistics that
are organized into a data structure and
stored in a database or in a data file.
 The data structure is based on
tabulations organized by time,
geography, or social content.

Aggregate Data

Data Structure
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Time
Geography
Social Content
Example:
CANSIM II
Aggregate Data
Time series data have long fueled
econometric models based on macroeconomic indicators.
 Comma-separate values (CSV) have
become an important format for time
series data, which is often manipulated
in Excel if not analyzed in a
spreadsheet.

Aggregate Data

Data Structure
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Time
Geography
Social Content
Example:
CENSUS
Aggregate Data
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Increased availability of GIS software has
created greater demand for Census statistics
organized as aggregate data.
Beyond 20/20 has become a popular tool for
reshaping census statistics from 1996 and
2001 for use with GIS software.
DBF is the most commonly used format to
share census statistics with GIS software.
Aggregate Data
A map from E-STAT of
Montreal Census
Tracts
Aggregate Data

“Small area statistics” are a special
category of aggregate data. These data
files consist of statistics for small
geographic areas usually calculated
from a population or manufacturing
census or an administrative database
with enough cases to create accurate
summaries for small areas.
Aggregate Data
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Data Structure
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Time
Geography
Social Content
Example:
Cause of Death (HID)
Aggregate Data

Also known as “cross-classified” tables,
these files tend to be made of statistics
constructed from social-content
variables. Examples of cross-classified
tables in DLI are found in education and
justice.
Framework of Statistical
Information
Statistical Information
Statistics
In print
Data
Online
Aggregate
Microdata
Microdata
E-publications
E-tables
Databases
Microdata
This is raw data organized in a file
where the lines in the file represent a
specific unit of observation and the
information on the lines are the values
of variables.
 There are different types of microdata
files, which will now be discussed.

Confidential Microdata

Master files: these files contain the
fullness of detail captured about each
case of the unit of observation. This
detail is specific enough that the identify
of a case can often be disclosed easily.
Therefore, these files are treated as
confidential.
Confidential Microdata
Share files: these are confidential files
in which the participants in the survey
have signed a consent form permitting
Statistics Canada to allow access to
their information for approved research.
 These files consist of a subset of the
cases in the master file.
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Confidential Microdata
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In summary, confidential microdata get
grouped into two types:
– master files and share files.
Public Use Microdata
These microdata are specially prepared
to minimize the possibility of disclosing
or identifying any of the cases in a file,
i.e, participants in a survey.
 The original data from the master file
are edited to create a public use
microdata file.
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Public Use Microdata
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Steps in Anonymizing Microdata
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Remove of all personal identification
information (names, addresses, etc);
Include only gross levels of geography;
Collapse detailed information into a smaller
number of general categories;
Cap the upper range of values of variables with
rare cases;
Suppress the values of a variable; or
Suppress entire cases.
Public Use Microdata

Statistics Canada PUMFs
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Only available for select social surveys that
undergo a review of the Data Release
Committee, an internal Statistics Canada
committee.
No ‘enterprise’ public use microdata.
Public Use Microdata
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Statistics Canada PUMFs
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Almost all PUMFs consist of cross-sectional
samples, that is, samples where the data
have been collected from respondents at
one point in time.
Longitudinal samples, where data are
collected from the same individuals two or
more times, are difficult to anonymize and
maintain any useful information.
Synthetic Microdata
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These data files have been created to
assist with the analysis of confidential
data files.
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The files provide the full variable structure
of the confidential microdata but do not
contain any real cases.
They are intended to be used by
researchers wanting to submit a file of
commands in a statistical package’s
language for remote job submission.
Synthetic Microdata
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They are also being used by those with
approved projects in Research Data
Centres to help prepare their analysis
strategies prior to working in an RDC.
Synthetic files are also commonly referred
to as “dummy files,” although a more
technical use of this term does exist for this
specific type of synthetic file.
Synthetic Microdata
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A variety of synthetic file types are being
created and tested by author divisions.
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One type has no real data but does contain a
complete set of real variables. This type is the
more technical reference to a dummy file.
Another type has a mix of real data but no real
cases. The purpose of this type is to provide -in the aggregate -- results that should be close
to an analysis of the real microdata file.
Synthetic Microdata
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Users of these files must be advised that none
of the analytic results from these files should
ever be reported. Their only purpose is to
help researchers construct their statistical
analysis programs to guard against syntax
errors that might exist in their setup.
Framework of Statistical
Information
Statistical Information
Statistics
Data
In print
Online
Aggregate
E-publications
E-tables
Databases
Microdata
Framework Summary
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This framework provides a way of thinking
about the types of statistical information
that exist.
Is the information Statistics or Data?
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If Statistics, is the information in print or
online?
 If
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online, is it in an e-pub, e-table, or database?
If Data, is the information aggregate data or
microdata?