Brief notes on Physical Quality of Life Index (PQLI)
In 1979, D. Morris constructed a composite .Physical Quality of Life Index (PQLI) He found that most of the indicators were inputs to development process rather than result of the development process. These indicators reflected that economically less developed countries are simply underdeveloped versions of industrialized countries.
He, therefore, combines three component indicators of Infant Mortality, Life Expectancy and Basic Literacy to measure performance in meeting the basic needs of the people. However, the choice of indicators is
1. Life Expectancy Indicator (LEI)
2. Infant Mortality Indicator (IMI)
3. Basic Literacy Indicator (BLI)
These three indicators can be improved in a variety of ways. However, Prof. Morris used Life Expectancy (LE) at birth as the indicator. Infant mortality implies deaths before age one instead of life expectancy at birth.
In case, the figure for life expectancy at age one was not available, it could be worked out by using a formula which relates life expectancy at birth, infant mortality and the proportion of children.
How to Normalize Indicators
We are familiar that life expectancy is measured in terms of years, infant mortality rate in terms of per thousand and basic literacy rate in terms of percentage. They can Indian Economic Development and Elementary Statistics not be simply added.
Moreover, basic literacy can have a natural zero for minimum and 100 for maximum, thus there exists no natural minimum or maximum values for other indicators. For comparison, each of the levels should be normalized. Prof. Morris chose the best and worst levels in each of the three cases.
In the case of positive indicators of life expectancy and basic literacy, the best is shown by the maximum and worst by the minimum. While in case of negative indicator of infant morality, the best is denoted by the minimum and the worst by the maximum.
For converting the actual levels of a positive variable into normalized indicators, first the minimum values are subtracted from the actual values and then the gap is divided by the range. For positive indicators, the formula is:
Achievement Level= Actual Value - Minimum Value / Maximum Value - Minimum Value
For negative indicator of infant mortality, actual value has to be subtracted from the maximum value and the gap if any has to be dividing by the range. The formula is
Achieve mental Level =Minimum Value - Actual Value / Maximum Value - Minimum Value
If not shell, there indicators are averaged to give what is called the Physical Quantity of life Index (PQLI).
PQLI= (1/3) (LEI + IMI +BLI)
Choice of Minimum and Maximum Values:
In case of life expectancy and infant morality, there exist no natural minimum and maximum values. The conversions from values to indices are linear. Put the actual value of these indicators of the country in the expression and get the reasonable indices as Physical Quantity of Life Index.