Quantifying the Unquantified Jim Burns

How to Include u Customer Satisfaction u Market Attractiveness u Quality of Life u Consumer Confidence u Faculty Morale u Material Standard of Living u IN YOUR MODEL

Often these are Unquantified u Begin by defining what one unit of any of these would be u Consider Quality of Life u One unit of Quality of Life might be the level of quality enjoyed in the year 1999 u Define this to be a Parameter called Quality of Life Normal u Quality of Life Normal = QLN = 1

What sort of things affect Quality of Life on a global scale? u Pollution u Material Standard of Living u Food u Population density

For each of these, construct a ratio u Pollution ratio = Pollution normal/Pollution u Here pollution normal is the amount of pollution experienced in the year 1999, in pollution units u MSL ratio = MSL/MSL normal u Here, MSL normal is the amount of MSL experienced in the year 1999, in MSL units u Food ratio = Food/ Food normal u Again, Food normal is the amount of food available in the year 1999, in Food units u Crowding ratio = Population density normal/Population density u again, Population density normal is the population density in the year 1999, say

What about Units? u For some of our soft variables the units are undefined u We have to define them u For example, one unit of pollution could be defined as “the average aggregate level of pollution experienced by a “typical” earthling in the year 1999” u One unit of Quality of Life could be “the average aggregate level of quality of life experienced by a ‘typical’ earthling in the year 1999.”

Under Normal Conditions, u What is true about all of these ratios? u What is the dimensionality of these ratios?

We can now construct our Quality of Life Formula u Quality of Life = QLN * Pollution ratio * MSL ratio * Food ratio * Crowding ratio u Is this formula dimensionally consistent? u Under normal conditions, Quality of Life = ?? u If pollution gets higher than normal, what happens to quality of life, assuming everything else remains the same? u If food is higher than normal, what happens to quality of life, assuming everything else is the same?

The VENSIM Representation

What if we felt that Material Standard of Living affected birth and death rates? u BR = BRN * POPULATION *MSL ratio u MSL ratio = MSL / MSL Normal u Does this change the dimensionality of the BR formula? u Under “normal” conditions what effect does Material Standard of Living have on BR, birth rate? u Similarly for death rate

We could do something similar for food... u BR = BRN * POPULATION * MSL ratio * Food ratio u And for pollution…. u BR = BRN * POPULATION * MSL ratio * Food ratio * Pollution Ratio u And for crowding…. u BR = BRN * POPULATION * MSL ratio * Food ratio * Pollution Ratio * Crowding Ratio

Suppose that we believe that the effect on births of an increase in food is less than the ratio would suggest u We can amplify or attenuate the effect of non-normal conditions with the use of TABLE FUNCTIONS u We call these multipliers u They are also dimensionless

Ratios vs. Multipliers

The new formula is: u Quality of Life = QLN * quality pollution multiplier * quality material multiplier * quality food multiplier * quality crowding multiplier u It must be accompanied by the following equations u quality pollution multiplier = TABLE(pollution ratio) u quality material multiplier = TABLE(MSL ratio) u quality food multiplier = TABLE(Food ratio) u quality crowding multiplier = TABLE(Crowding ratio)

Similarly for Birth rate u BR = BRN * POPULATION * births material multiplier * births food multiplier * births pollution multiplier * births crowding multiplier u It must be accompanied by the following equations u births pollution multiplier = TABLE(pollution ratio) u births material multiplier = TABLE(MSL ratio) u births food multiplier = TABLE(Food ratio) u births crowding multiplier = TABLE(Crowding ratio)