PECAS Model Development
Analyzing PECAS output results with MapIt
Tech Memo 2 – WORKING DRAFT
Calgary, Alberta
November 2011
PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
1. Introduction
This brief document has the purpose to explain why HBA creates MapIt? What is MapIt? How to
access or open MapIt? What are the prerequisite in terms of data and software? And, how to use
Mapit?
Three illustrative examples are presented in this report in order to show and explain how to use
MapIt. The first example is about changes in price in one scenario during a period of time; the
second example, is regarding changes in household quantities in two different scenarios during a
period of time; and the third example shows changes in non-residential floorspace in one scenario
considering a period of time.
Besides this document, there is another piece of documentation called ‘MapIt Installation and
Configuration’ that explains in detail the installation of the program.
2. Why HBA creates MapIt?
PECAS as other spatial economic models needs to handle a lot of spatial information. There are two
specific periods when it is particularly relevant to revise the output results of PECAS model: during
the base year calibration process and during the tests of future year’s policy scenarios. Even if
geographic information system (GIS) softwares are used to visualize PECAS results, to organize the
information in a specific way for the correspondent revision, is very demanding in terms of time
consuming and effort. Many times it includes not only the revision of one scenario, but several
scenarios from different years and the comparison between each policy scenario with the base
scenario.
In order to facilitate or make faster and easier the final visualization of the PECAS output results,
HBA decided to create ‘MapIt.’ This is a tool that combines PECAS outputs into layers in a geodatabase and generates these outputs in shape files (which is the one of the standard format in GIS
software).
In addition, MapIt allows PECAS user to visualize results from a single scenario or visualize a
comparison of scenarios showing the spatial pattern of a specific variable included in the query by
the user, e.g. prices, quantities and zonal utilities. It is also the user who specifies the level of
geography for the analysis. And, even if the user does not have a GIS software to perform further
analysis, MapIt allows the user to visualize the PECAS output results.
3. What is MapIt?
MapIt is a tool developed by HBA Specto that provides support to a group of tasks involved in every
day PECAS modelling work. MapIt allows users to visualize PECAS model results in the form of maps
at the LUZ (land use zones) and TAZ (transportation analysis zones). MapIt runs on a webserver and
interacts with a database, so that multiple users can simultaneously use it to investigate model run
results.
Users define their own query in terms of: scenarios (one or two), which file (ActivityLocations,
ExchangeResults, others), which attributes (prices, quantities, utilities, etc.), start year and end year.
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
MapIt then shows a list of options depending on the file selected. For example, MapIt shows activity
groups or commodity groups based on the file previously chosen.
Two features make MapIt essential in PECAS modelling work:
 It compares the results from 2 different scenarios (for instance W00 and C01).
 It combines values from different years.
Although MapIt generates rudimentary maps, its main purpose is to combine PECAS outputs into
layers in a geodatabase and in shape files. Users can then use the GIS and visualization tools they
are comfortable with to view PECAS output.
MapIt is used by HBA staff to build numeric comparison between scenarios and years and store the
instructions for the comparison in the database. Users can download these comparisons as GIS
shape files, or view them from the GIS database. These comparisons are used in calibration and
development (plan an implement future changes or improvements in the models) and in policy
evaluation and analysis. Figure 1 shows MapIt interface.
Figure 1. MapIt interface
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
4. Prerequisites to use it:
To use MapIt the user needs:
1. MapIt should be installed and configured in your machine or in the server
2. The project database should be in PostgreSQL 8.4 (pgAdmin III) format and the outputs should
be stored in tables inside of a schema called ‘Output’. For example, Oregon database with the
results in Output schema
3. Shape files or layers you want to link with the output results from PECAS. For example, TAZ, LUZ,
Beta Zones or another level of geography defined for the project
4. User needs to know which file has which information
To help with this last item, a table with the content of the output has been placed bellow:
AA Output Files
Description
[CommodityZUtilities.csv]
Commodity make and use quantities and composite utilities
regarding buying and selling by LUZ
[ActivityLocations.csv]
Activity quantities and composite utilities for LUZ and TAZ
Prices and quantities for each commodity exchange (by LUZ and
commodity type)
[ExchangeResults.csv]
[ZonalMakeUse.csv]
Solved LUZ industry-commodity production and consumption
technical coefficients (binary)
[FloorspaceI.csv]
Quantities of total floorspace inventory by TAZ (or by LUZ)
5. To access and run MapIt
MapIt can be accessed and run by typing this URL in a web browser: http://<IP address of
MapServer>/(name of the database, e.g. Baltimore)/mapit.
For example, if MapServer is installed on computer (IP: 192.168.90.105). Then, MapIt URL is:
http://192.168.90.105/(name of the database, e.g. Baltimore)/mapit or if MapServer is installed in your
machine, then MapIt URL is http://localhost/(name of the database, e.g. Baltimore)/mapit
Once you type the referenced URL, you should be able to see the MapIt menus as shown in Figure 2.
Figure 2. Accessing MapIt
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
6. Analyzing PECAS output with MapIt:
The user build the queries selecting the options needed for the analysis. To show how the output results
can be visualized using MapIt, three examples are presented:



6.1
Changes in prices of low density residential space in scenario S20 between 2000 and 2015
Changes in household’s quantities between scenario S20 and scenario S30, since year 2000 until
2020
Changes in non-residential floor space in scenario S20 between 2010 and 2020
Example 1. Changes in prices of low density residential space in scenario
S20 between 2000 and 2015
To start, press home. Then, select the option work with one scenario then select the file Exchange
Results.csv (Figure 3).
Figure 3. MapIt home - choosing scenarios and the file
Choose an attribute; in this case price was selected for the analysis (Figure 4).
Figure 4. MapIt – choosing the attribute
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
Choose which scenario you want to revise; in this case S20 was selected (Figure 5):
Figure 5. MapIt – choosing the scenario
Choose Start year and End year in the menu (Figure 6):
Figure 6. MapIt – start year and end year
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
Choose a Commodity group or an Individual Commodity (Figure 7):
Figure 7 MapIt – choosing the commodity
Depending on the previous selection (commodity group or an individual commodity) the user can decide
what option selects for the Aggregate grouping function. For example, if an option from the
Commodity Group was choosen, then for the aggregate grouping function Average should be selected
(Figure 8).
Figure 8 MapIt – choosing the aggregate grouping function
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
Then, press the button Create DB view and a window with the map will be opened at the bottom of the
window as it is shown in Figure 9.
Figure 9 MapIt – visualizing the output results in the map
If we press the button Show Map! a new tab will be open with the map allowing the user to change the
zoom moving the vertical command in the left side on the window. In addition, the user can check the
data of a specific zone making a single click on the zone. This action will display a window bellow the
map with the results for each year included in the analysis. The number of the zone is indicated in the
plot (x-axis) and on the left of the plot a summary of the difference (delta) is presented (Figure 10).
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
Figure 10 MapIt – visualizing a detail of the output results by zone
To use the Export as a shape file functionality just press the button and a zip file will show up including
all the files needed to open the shape file in a GIS software. In this particular case the file name
generated is called ‘S20_low_density_res_111110_130911_with the geom’ (Figure 11)
Figure 11 MapIt – exporting output results in a shape file
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
In order to see in detail the internal database produced by MapIt, the shape file was open in
QuantumGIS. The figure bellow shows in detail the fields of the table. Zone 20100 was selected to see
the output results (Figure 12).
Figure 12 MapIt – visualizing output results in QuantumGIS
6.2
Example 2. Changes in household’s quantities between scenario S20 and
scenario S30, since year 2000 until 2020
To build the query for this example the user should select compare two scenarios and then select the
file ActivityLocations.csv (Figure 13)
Figure 13 MapIt – choosing scenario options and the file
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
After that, the user should select the options to build the query. The selections should be made in the
following order as it is shown in Figure 14:







An attribute (for this example, quantity)
The first scenario (for this example, S20)
An operator (e.g. minus, division, relative change, relative difference)
The second scenario (for this example, S30)
Start year and End year (for this example, 2000 and 2020 respectively)
Activity or activity group (for this example, households)
Aggregate grouping function (households is a activity group then Average was selected as an
aggregate grouping function).
Figure 14 MapIt – choosing options to build the query
As a result, three maps are created by Mapit:
 A map with the households estimated from 2000 to 2020 for the scenario S20
 A map with the households estimated from 2000 to 2020 for the scenario S30
 A map with the household comparison estimated from 2000 to 2020 for scenario S30 minus
scenario S20
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
Figure 15 presents a map with the quantity of households estimated from 2000 to 2020 for the scenario
S20
Figure 15 MapIt – visualizing output results from S20
Making click in the previous map, the user can make zoom and pan in the map. Once in the new map
the user can click on one zone. This will display a plot with the output for the selected zone (e.g. in this
case zone 12203). The user can check the information putting the cursor on each bar of the plot; the
number or households come up for that year. On the left, it can be seen the difference in households for
this zone between 2000 and 2020. (Figure 16).
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
Figure 16 MapIt – visualizing output results by zone from S20
Figure 17 presents the quantity of households estimated from 2000 to 2020 for the scenario S30
Figure 17 MapIt – visualizing output results from S30
The data for the same zone 12203 can be checked but now for the scenario S30. On the left, it can be
seen the difference in households for this zone between 2000 and 2020. In this scenario is 72
households (Figure 18).
Figure 18 MapIt – visualizing output results by zone from S30
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
This map presents the comparison of households (HH) estimated from 2000 to 2020 between the
scenario S20 and the scenario S30. Note that the bars are facing down in some zones which means that
probably the number of HH decrease in some zones in the future while probably other activity increase
the use of space in that zones (Figure 19).
Figure 19 MapIt – visualizing output results from the S20 and S30 comparison
The data for the same zone 12203 can be checked but now for the scenario comparison. On the left, the
difference in households that is shown for this zone corresponds to the difference for the year 2020
(Figure 20).
Figure 20 MapIt – visualizing output results by zone from the S20 and S30 comparison
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
6.3
11.10.2011/GFM/JEA
Example 3. Changes in non-residential floorspace in scenario S20 between
2010 and 2020
To build the query of this example the user should follow the same steps showed in the two previous
examples. This query is regarding changes in non-residential floorspace in the scenario S20 between
2010 and 2020. The image below shows the selections the user should make and the resulted map
(Figure 21).
Figure 21 MapIt – visualizing output results (floorspace) from the S20
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PECAS Model Development: Analyzing PECAS output with MapIt
System Documentation Technical Note
File: Analyzing PECAS with MapIt.docx
11.10.2011/GFM/JEA
Note that non-residential space only increase in specific zones. The figure below shows the detail of
these changes in the zone 127 for each year of the evaluation period.
Figure 22 MapIt – visualizing output results (floorspace) by zone from the S20
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