Reliability of data
The reliability of data is a serious concern. One is inclined to assume published figures to be correct and reliable. However, this is certainly way too optimistic. Particularly when producing time series one is confronted with many irregularities and impossibilities in the data. This problem will decrease over time, since the importance of sound statistical data is now generally recognized. For example, the Stiglitz report also calls for increasing efforts by countries and statistical offices.
Aggregation
Opinions concerning aggregation vary enormously. For some it is an absolute ‘don’t’, others simply do it. In view of the objectives of the SSI – among others to show at a glance the level of sustainability of a country – an aggregation has been made from indicators into categories and from categories into wellbeing dimensions and finally into one single figure for the SSI.
We do realise the objections one may have, one of these being a possible trade-off between the indicators. However, since all 24 indicators must receive a score of 10 (on a scale of 0 to 10) to achieve full sustainability, a trade-off will not be sufficient to achieve full sustainability.
For those who object to aggregation and are only interested in the underlying figures, we present all available data. Thus the user may make its own choice: focus on the overall index or on the underlying figures. Or on both.
Calculation methodology
For lack of a scientific basis for the attribution of different weights to the indicators, every indicator has received the same weight for the aggregation into categories. The same applies for the aggregation into the three wellbeing dimensions. Since there is an inequality among the three dimensions – two comprising three categories and one comprising two categories – the overall index SSI has been calculated directly as the unweighted average of the 24 indicators.
Note that the calculation of world totals is based on the unweighted average of 151 countries. Should one use a calculation based on weighting of population size per country, the results would be different.
Calculation formulas
If you are interested in the formulas used to calculate the indicators, you can have a look at the file you can download here. For each indicator the formula is shown, in which F(X) is the indicator score and X the value of the raw data. In addition the range of validity is indicated.
The graphs show the resulting scores for the 151 countries included in the SSI, visualizing the range of Indicator scores and the range of raw data values.
Download the Calculation Formulas
