Function to find QME estimates of the regression coefficients for regression models with truncated response variables. Uses optim. Intended to be called through qme, not on its own, since qme also transforms data into the correct form etc.
Functions for estimation of semi-parametric linear regression models with truncated response variables (fixed truncation point). Estimation using the Symmetrically Trimmed Least Squares (STLS) estimator (Powell 1986), Quadratic Mode (QME) estimator (Lee 1993) and Left Truncated (LT) estimator (Karlsson 2006).
Function that utilizes optim to find STLS estimates of the regression coefficients for regression models with truncated response variables. Intended to be called through stls, not on its own, since stls also transforms data into the correct form etc.
Estimation of linear regression models with truncated response variables (fixed truncation point), using the Quadratic Mode Estimator (QME) (Lee 1993 and Laitila 2001)
Function to find LT estimates of the regression coefficients for regression models with truncated response variables. Uses optim. Intended to be called through lt, not on its own, since lt also transforms data into the correct form etc.
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