Thanks to Louis and to Ulhas for pointing out the recently released Human Development Index 2004 and Doug for his comments. I want to make a somewhat different point about indexes themselves - caution about their use.
Social, economic and political "indexes" have become a popular tool among think tanks, NGOs and in official governmental organizations - for some of the most important uses (such as allocating aid funds or assessing policies) they now often replace the use of the underlying data itself. Constructing mathematical indexes to present disparate data in a "consolidated" manner parallels the long-standing trend in Economics of presenting extensive mathematical or econometric models - and it falls into several similar traps. These newly emerging socio-economic indexes often use extraordinary arithmetical measures whose methods are not available to 99% percent of those who read the reports. I find three problems often appear:
1) Indexes (which inherently combine 'apples and oranges') often do so in arbitrary and misleading ways that are not accessible to 99% of the users. While at first glance there are enough similarities to the original data to make the index seem plausible, the flaws show up as the data gets put to use in important judgements (such as whether there is relative progress over time, or the value of particular controversial policies). Frequently these flaws show up with a bias.
For example at http://hdr.undp.org/reports/global/2004/pdf/hdr04_backmatter_2.pdf you will see how the Human Development Index (HDI) is constructed. It merges data from 3 fields (health, education and GDP), so first it creates an index ("normalizing") of each one. The health proxy is the least problematic: life expectancy of 85 years is = 100; 25 years = 0. But now we are not measuring years of life but numbers on the index and this can (and does) affect the final conclusions in unforeseeable ways. I will come back to the indexes on Education and GDP.
The three indexes numbers are then merged into one index number: decided as 1/3 for each factor. (I am not making this up!) So one assumes that an index number of say 10 points in education equals an index number of 10 points in health or GDP and that they can be merged even though these index numbers themselves are arbitrarily chosen, correspond to nothing in the real world and can not be logically added together.
2) Some index numbers have other indexes or artificial constructs nested inside them, making them an arbitrary index of arbitrary indexes.
For example in the HDI (per the website above), the education index contains an (arbitrary) literacy index and an (arbitrary) enrollment index mixed in (arbitrary) 2/3rds to 1/3 proportion.
The most problematic is the GDP per capita element which is not, in itself, a human development indicator at all. In fact this index uses the PPP "version" of GDP - a vast recalculation of the GDP that has an enormous amount of arbitrary (and biased!) assumptions that create an "as if" world rooted in neo-classical trade theory [too much to elaborate in this post]. The PPP numbers produce numbers that narrow the gap between most developing and developed countries AND continue to show that gap narrowing over time (mostly because PPP assumes a world AS IF 3rd world labor could freely trade in the developed world market). PPP also shows the US significantly richer than Europe (mostly because it assumes a US based market basket AS IF Europeans strived to live an American style life). For no intrinsic reason (these are apples and oranges) the disparities in income numbers are larger than the numbers produced for health and education, so it is the natural logarithm of the PPP "version" of GDP/p.c. that is used (?!).
3) All of these "index" calculations create proxies of proxies. However inaccurate or biased they are (or are not), one is no longer debating the real problems of real people. Rather, one debates the meaning or the construction of indexes. The focus shifts from mass movements to policy analysts and negotiators. There are clear allies (and de facto opponents) of an effort to end unnecessary child deaths in the 3rd world or to provide functional literacy for every adult. But debates among NGOs, academics, and development officials about "raising the human development index" is not process that necessarily leads to mobilization of those allies in a common movement.
In short, the indexes can sometimes take one away from a focus on the practical reality or actual people and lead away from the social processes that produce change.
It is not that I am against all indexes for all uses (and the HDI is among the most benign). But as analytical and as mobilizing tools they have to be treated at arms length - above all one has to look 'under the hood'.
Paul
