IDEAS home Printed from
   My bibliography  Save this article

Constructing a summary index using the standardized inverse-covariance weighted average of indicators


  • Benjamin Schwab

    () (Kansas State University)

  • Sarah Janzen

    () (University of Illinois at Urbana Champaign)

  • Nicholas P. Magnan

    () (University of Georgia)

  • William M. Thompson

    () (IDInsight)


Researchers often want to examine the relationship between a variable of interest and multiple related outcomes. To avoid problems of inference that arise from testing multiple hypotheses, one can create a summary index of the outcomes. Summary indices facilitate generalizing findings and can be more powerful than individual tests. In this article, we introduce a command, swindex, that implements the generalized least-squares method of index construction pro- posed by Anderson (2008, Journal of the American Statistical Association 103: 1481–1495). We describe the command and its options and provide an example based on Blattman, Fiala, and Martinez’s (2014, Quarterly Journal of Economics 129: 697–752) evaluation of a cash transfer program in Uganda.

Suggested Citation

  • Benjamin Schwab & Sarah Janzen & Nicholas P. Magnan & William M. Thompson, 2020. "Constructing a summary index using the standardized inverse-covariance weighted average of indicators," Stata Journal, StataCorp LP, vol. 20(4), pages 952-964, December.
  • Handle: RePEc:tsj:stataj:v:20:y:2020:i:4:p:952-964
    DOI: 10.1177/1536867X20976325
    Note: to access software from within Stata, net describe

    Download full text from publisher

    File URL:
    File Function: link to article purchase
    Download Restriction: no

    More about this item


    swindex; index construction; GLS;
    All these keywords.


    Access and download statistics


    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:tsj:stataj:v:20:y:2020:i:4:p:952-964. 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: (Christopher F. Baum) or (Lisa Gilmore). General contact details of provider: .

    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.

    We have no references for this item. You can help adding them by using 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 RePEc Author Service 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.

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.