IDEAS home Printed from
MyIDEAS: Login to save this paper or follow this series

Quantile Uncorrelation and Instrumental Regression

  • Tatiana Komorova
  • Thomas Severini
  • Elie Tamer

We introduce a notion of median uncorrelation that is a natural extension of mean(linear) uncorrelation. A scalar random variable Y is median uncorrelated with a kdimensionalrandom vector X if and only if the slope from an LAD regression of Yon X is zero. Using this simple definition, we characterize properties of medianuncorrelated random variables, and introduce a notion of multivariate medianuncorrelation. We provide measures of median uncorrelation that are similar to thelinear correlation coefficient and the coefficient of determination. We also extendthis median uncorrelation to other loss functions. As two stage least squaresexploits mean uncorrelation between an instrument vector and the error to deriveconsistent estimators for parameters in linear regressions with endogenousregressors, the main result of this paper shows how a median uncorrelationassumption between an instrument vector and the error can similarly be used toderive consistent estimators in these linear models with endogenous regressors.We also show how median uncorrelation can be used in linear panel models withquantile restrictions and in linear models with measurement errors.

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.

File URL:
Our checks indicate that this address may not be valid because: 500 Can't connect to (10060). If this is indeed the case, please notify ()

Download Restriction: no

Paper provided by Suntory and Toyota International Centres for Economics and Related Disciplines, LSE in its series STICERD - Econometrics Paper Series with number /2010/552.

in new window

Date of creation: Sep 2010
Date of revision:
Handle: RePEc:cep:stiecm:/2010/552
Contact details of provider: Web page:

No references listed on IDEAS
You can help add them by filling out this form.

This item is not listed on Wikipedia, on a reading list or among the top items on IDEAS.

When requesting a correction, please mention this item's handle: RePEc:cep:stiecm:/2010/552. 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: ()

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.

This information is provided to you by IDEAS at the Research Division of the Federal Reserve Bank of St. Louis using RePEc data.