IDEAS home Printed from https://ideas.repec.org/p/ias/cpaper/92-wp99.html
   My bibliography  Save this paper

Semiparametric Transformation Approach to Estimating Usual Daily Intake Distributions, A

Author

Listed:
  • Sarah M. Nusser
  • Alicia L. Carriquiry
  • Wayne A. Fuller

Abstract

The distribution of usual intakes of dietary components is important to individuals formulating food policy and to persons designing nutrition education programs. Usual intake of a dietary component for a person is the long run average of daily intakes of that component for that person. Because it is impossible to directly observe usual intake of an individual, it is necessary to develop an estimator of the distribution of usual intakes based on a sample of individuals with a small number of daily observations on each individual. Daily intake data for individuals are nonnegative and often very skewed. Also, there is large day-to-day variation relative to the individual-to-individual variation and the within-individual variance is correlated with the individual means. We suggest a methodology for estimating usual intake distributions that allows for varying degrees of departure from normality and recognizes the measurement error associated with daily dietary intakes. The estimation method contains four steps. First, the original data are standardized by adjusting for weekday and interview sequence effects. Second, the daily intake data are transformed to normality using a combination of power and grafted polynomial transformations. Third, using a normal components-of-variance model, the distribution of usual intakes is constructed for the transformed data. Finally, a transformation of normal usual intakes to the original scale is defined. The approach works well for a set of dietary components selected from the 1985-1986 Continuing Survey of Food intakes by Individuals data. The selected components display a range of distributional shapes.

Suggested Citation

  • Sarah M. Nusser & Alicia L. Carriquiry & Wayne A. Fuller, 1992. "Semiparametric Transformation Approach to Estimating Usual Daily Intake Distributions, A," Center for Agricultural and Rural Development (CARD) Publications 92-wp99, Center for Agricultural and Rural Development (CARD) at Iowa State University.
  • Handle: RePEc:ias:cpaper:92-wp99
    as

    Download full text from publisher

    File URL: https://www.card.iastate.edu/products/publications/pdf/92wp99.pdf
    File Function: Full Text
    Download Restriction: no

    File URL: https://www.card.iastate.edu/products/publications/synopsis/?p=628
    File Function: Online Synopsis
    Download Restriction: no

    Corrections

    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:ias:cpaper:92-wp99. 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: (). General contact details of provider: http://edirc.repec.org/data/caiasus.html .

    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.