ON INCREASING TREATMENT CONTRAST PRECISION AND THE ESTIMATION OF STRUCTURAL PARAMETERS IN COVARIANCE ANALYSIS

Abstract

Analysis of covariance in randomized and balanced incomplete block designs is reconsidered in terms of structural regression. In practice, the covariable is usually uncontrolled and may follow a linear model as does the variable of interest. If the covariable and treatments are independent, then the covariable model contains no treatment effect, and the treatment contrast precision on the variable of interest is increased, not only asymptotically, but in the finite sample. If the covariable is affected by one more of the treatments, then the estimation of direct and indirect effects is considered. Finally, when structural parameters are underidentified, in which case direct and indirect effects are not estimable, an alternative estimation procedure is discussed.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1964
Accession Number
AD0603563

Entities

People

  • William S. Mallios

Organizations

  • Booz Allen Hamilton

Tags

Communities of Interest

  • C4I

DTIC Thesaurus Topics

  • Biological Laboratories
  • Combinatorial Analysis
  • Compressive Strength
  • Contrast
  • Covariance
  • Efficiency
  • Equations
  • Estimators
  • Iterations
  • Measurement
  • Moisture
  • Moisture Content
  • Normality
  • Plastic Explosives
  • Precision
  • Residuals

Fields of Study

  • Mathematics

Readers

  • Regression Analysis.