How should we assign weights to various aspects in the OECD's 'better life' index?

The second edition of the OECD’s ‘Better Life’ index is now available. As with the first edition, the index is presented in an interactive form.  Users are able to compare the quality of life in different OECD countries by assigning their own weights to a range of factors that are relevant to assessment of well-being.

When the first edition of the index came out I played around with it to see how different weighting systems and inclusion of additional information on factors, such as perceptions of freedom and corruption, might affect the comparisons. In order to make much difference I had to make some fairly extreme assumptions. My conclusion was that all well-being indicators tend to tell similar stories at a national level.

In this post I want to give some further consideration to the question of what weighting systems might be most appropriate. I want to allow for the possibility that because some of the factors included in the index measure similar aspects of well-being, there may be potential for users to inadvertently give excessive weight to the factors that seem important to them. For example, some people who assign a high weight to life satisfaction might also give high weight to factors that could be expected to have a strong influence on life satisfaction (e.g. jobs and work-life balance). That might mean that they end up giving excessive weight to factors that are strongly correlated with life satisfaction, at the expense of other factors (e.g. education and the environment).

The approach I have adopted in deciding on the weightings was to begin by giving highest weight (5/5) to safety (low crime), life satisfaction and the environment and then to assign weights to other factors depending on whether I consider their influence to be adequately reflected in the factors already covered. I have assigned a weight of 4/5 to income because I think high income adds to quality of life in ways that are not fully taken into account when people are asked whether they are satisfied with life (the value of the future security that a high income can provide). I have assigned a 4/5 weight to education because the contribution of education to quality of life may not be adequately reflected in either life satisfaction or income. Similar reasoning applies to community (covering support networks and volunteering). A weight of 3/5 is assigned to housing, jobs and health because these factors are already taken into account to a considerable extent in measures of life satisfaction and income. I have assigned a relatively low weighting (2/5) to civic engagement because important aspects of civic engagement are reflected in other factors (e.g. safety) and voter turnout seems to me to be a poor indicator of civic engagement in countries with compulsory voting. Finally, I have assigned a rating of 1/5 to work-life balance (rather than 0/5) because it might possibly cover some aspects of the quality of life that are not adequately reflected in other factors.

The ranking of countries according to the weights I have assigned can be found by clicking here. (The OECD offers a facility to embed it, but I am not clever enough to use it.)

The ranking according to my weights differs somewhat from the ranking if equal weights are assigned to all factors. The top five countries under my weights are: Australia, Switzerland, United States, Canada and Norway. With equal weighting, the top five countries are: Australia, Norway, United States, Sweden and Denmark.

However, this difference in rankings doesn’t mean a great deal because the difference in ratings of the top ranked countries is small. That doesn’t surprise me - all well-being indicators tend to tell similar stories at a national level!