Correcting the concentration index: A comment
In a recent article in this journal, Erreygers [Erreygers, G., 2008. Correcting the concentration index. Journal of Health Economics] has proposed a new measure of income-related health inequality to overcome three shortcomings of the concentration index (CI). I think Erreygers is absolutely right to probe on these issues, and I welcome his generalization of my normalization which was specific to the case of a binary health indicator. However, I have misgivings about his paper. His goal of correcting the CI so as to make it usable with interval-scale variables seems misguided. The CI reflects a commitment on the part of the analyst to measuring relative inequality. Armed only with an interval-scale variable, one simply has to accept that one can meaningfully measure only differences and therefore settle for measuring absolute inequality. Erreygers, index inevitably ends up as a measure of absolute inequality. His objection to my approach to getting round the bounds problem is that my normalization of the CI does not produce a measure of absolute inequality. But that was never my intention! In this comment I also show that - somewhat paradoxically at first glance - my index is also not a pure index of relative inequality. This seems to be an inevitable consequence of tackling the bounds issue.
If you experience problems downloading a file, check if you have the proper application to view it first. In case of further problems read the IDEAS help page. Note that these files are not on the IDEAS site. Please be patient as the files may be large.
As the access to this document is restricted, you may want to look for a different version under "Related research" (further below) or search for a different version of it.
When requesting a correction, please mention this item's handle: RePEc:eee:jhecon:v:28:y:2009:i:2:p:516-520. See general information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Zhang, Lei)
If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.
If references are entirely missing, you can add them using this form.
If the full references list an item that is present in RePEc, but the system did not link to it, you can help with this form.
If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your profile, as there may be some citations waiting for confirmation.
Please note that corrections may take a couple of weeks to filter through the various RePEc services.