:GRAPH WIP1
:TITLE WIP1
:X-MIN 0
:X-MAX 250
:SCALE
:VAR population
:GRAPH HISTORY
:WIP
:label-lines
:Title History of Conditions
:x-min 100
:x-max 250
:x-label Years
:var population|Total Population
:line-width 2
:y-min 0
:y-max 10e6
:Var underemployed crowding|Underemployed crowding
:y-min 0
:y-max 200
:units /100
:line-width 2
:scale
:VAR percent underemp|% of population underemployed
:line-width 2
:VAR unemployment rate|Unemployment rate
:units %
:y-min 0
:y-max 100
:line-width 2
:report COMM1
This game allows you to play with and understand a model through 
interaction and analysis.  Most screens have menu items.  To select
a menu item you can click on it, type the first letter, or highlight
it using the up and down arrow keys and press the enter key.  

The main gaming screen has buttons rather than menu selections.  Use
the mouse to click on a button and activate the associated action.

Additional functionality available in the software is described in 
places where it can be used.  To conserve space, later commentaries
will be kept small, and you will need to scroll them to read all the
information they contain.

The model used for this application is the Urban Dynamics model as 
published in the book Urban Dynamics by Jay W. Forrester (MIT Press,
Cambridge, MA 1969).
:end-of-report
:report comm3
You can do analysis of the model by first loading in scenarios of 
interest, and then reviewing the output or doing causal tracing.  
The Load and reorder command will put up a small window with two lists.  
On the left is a list of loaded scenarios, on the right a list of 
scenarios that have been run.  The << button loads scenarios.  Click 
on the scenario you want to load in the right hand list, and then 
click the << button.  The >> button unloads scenarios.  Click on the 
scenario you want to unload in the left hand list, and the click on 
the >> button.

You can load up to 8 scenarios at a time, but it is difficult to read
graphs with more than 4 scenarios loaded.

If the list on the right is empty, you will need to run some 
scenarios.  Exit back to the main menu and do this.  You can run
the scenarios described in "Beyond the Limits" by choosing one
of the named scenarios to base your scenario on, and running the
scenario without making any additional changes.

Causal tracing is a process the allows you to determine the underlying
causes of behavior, and differences in behavior between different
scenarios.  There are two options for doing causal tracing available.
The first uses tree diagrams and single graphs.  The second uses
equations and multiple graphs.  Try them both out to see which you
prefer.
:end-of-report
:report COMM4
The cause and use screens show lists of
different variables.  The graphs allows
your to compare different scenarios.
The trees allow you to investigate the
structure of the model.

You can double click on a variable name
in the graphs, trees or documentation to
view the same analysis screen for that
variable.  You can also use the S
command to select a new variable to work
with.

You can print the contents of the graphs
and trees using the P command.  Output
will be directed to your default printer.

During causal tracing you can switch
between the Tree and Graph represen-
tations of causes.  This can be
useful as means of understanding both
structure and behavior.
:end-of-report
:REPORT EXP1
Build low cost housing in order to improve the 
condition of the underemployed.  This is housing
units/person/year so that .2 means everyone should
have a new house in five year.
:END-OF-REPORT
:REPORT EXP2
Demolish slum housing.  Encourages new higher quality
housing and business growth, but at the expense of
available housing for the underemployed.  Measure in 
fraction/year destroyed.
:END-OF-REPORT
:REPORT EXP3
Programs to make jobs available to the underemployed.
Measured as the % of unemployed offered jobs.
:END-OF-REPORT
:REPORT EXP4
Job training programs.  Measured as the fraction/year of
underemployed trained.
:END-OF-REPORT
:REPORT EXP5
Construction of new business subsidized and/or directed
by the government.  Measures in fraction/year of existing
business the is created.
:END-OF-REPORT
:REPORT EXP6
Demolition of ailing businesses.  Buyouts and accelerated
shutdowns.  Measures in fraction/year removed.
:END-OF-REPORT