Recent Submissions

  • Moment estimation of measurement errors 

    O'Driscoll, Diarmuid; Ramirez, Donald E. (NEDETAS, 2011)
    The slope of the best-fit line from minimizing a function of the squared vertical and horizontal errors is the root of a polynomial of degree four. We use second order and fourth order moment equations to estimate the ratio ...
  • Revisiting some design criteria 

    O'Driscoll, Diarmuid; Ramirez, Donald E. (Athens Institute for Education and Research, 2015)
    We address the problem that the A (trace) design criterion is not scale invariant and often is in disagreement with the D (determinant) design criterion. We consider the canonical moment matrix CM and use the trace of its ...
  • Limitations of the least squares estimators; a teaching perspective 

    O'Driscoll, Diarmuid; Ramirez, Donald E. (Athens Institute for Education and Research, 2016)
    The standard linear regression model can be written as Y = Xβ+ε with X a full rank n × p matrix and L(ε) = N(0, σ2In). The least squares estimator is = (X΄X)−1XY with variance-covariance matrix Coυ( ) = σ2(X΄X)−1, where ...