Index Project: Preparing Preferences
 
Preferences are not a simple matter of YES/NO; rather thay are BETTER/WORSE.  The preferences will be applied to those places which remain after all the requirements have been applied. Preferences will be used to index the qualifying places.  Here are some examples of preferences: "the warmer the winter, the better," (refer to heating degree days), "the closer to Chicago, the better," (refer to a distance calculation from Chicago), "the better educated the better," (refer to percent over 25 years of age with a college degree). 

A variable which you use as a requirement may also be used as a preference.  For example, "I must live within 100 miles of an ocean, but within that zone, the closer to the ocean, the better."  You'd use a condition "within 100 miles of ocean" to eliminate all nonqualifying places, and then calculat the actual distance to the coast for each remaining place (see below).
  1. Make a list of things you like and don't like -- these things can be less important to you than requirements.
  1. Look carefully for highly correlated  preferences.  For example, higher income areas and areas with higher values of homes would be measuring pretty much the same thing.  Choose one.
  1. You should end up with at least 3 preferences, possibly four.
  1. Operationalize these variables by finding data from the list of prepared layers/attribute tables, year 2000 census, addresses you might have, or any other resource at your disposal.  Translate the conceptual to the operational, as I have done here...

 

CONCEPTUAL OPERATIONAL SOURCE LAYER
In a racial/ethnic mix Absolute Value differnce from  60-<percent white> Census data Place 
Near family/friends Distance from county centroid to Chicago Centroid calc County and CityPoint
In a middle-income area Percentage of households between 50-75,000 annual Census data Place

To be clear: In preparing your preferences you do not assign a threshold value, like you did with requirements.  In other words you do not say "within 20 miles of a lake which is more than 10 square miles in size."  Instead you say "near a lake that is more than 10 square miles in size."  The attribute table will have a field called "distance from large lake," with gives you the distance from the nearest qualifying lake -- a different value for each place.

Each of your 3 or 4 preferences will result in a single field in the place layer in which a bigger value is better or a bigger value is worse.
 

  1. Weight each preference as so: "on a scale of one to ten," how important is this preference to me?
    1. this will allow some preference to matter more than others.  It's purely a subjective weight, and it will influence your results only in the relative size of the various weights.  In other words if you weight three preferences with an 8, 2, and 8 then the first and last ones will each be four times as important as the second one.

 

 

PREFERENCES RATING
Close to parents' home 5
Near Coast 8
Higher income area 6
These "weights" will be applied later.

For today's assignment, fill out this table carefully:
You may download this page, and in Composer delete all but this table.  Type your information into the cells.  Then publish this table.

PREFERENCES (3 or 4*)  * if you had 3 requirements, you need 4 preferences.

Conceptual -- describe your preferences, explain why.
Operational -- how will you measure these.  Be specific!
Where will you get the necessary data?
Weight 
(1-10)
Will your preference require preparation or formula?  Explain.
         
         
         
         

If you are confident and have finished your requirements, you may prepare your columns representing your formulas.
Otherwise, apply your requirements!