DALSM.object: Object resulting from the fit of a double additive...

DALSM.objectR Documentation

Object resulting from the fit of a double additive location-scale model (DALSM).

Description

An object returned by the DALSM function: this is a list with various components related to the fit of a double additive location-scale model using Laplace P-splines.

Value

A DALSM object has the following elements:

Essential part:

  • converged : ⁠ ⁠logical convergence indicator.

  • derr : ⁠ ⁠estimated standardized error distribution returned as a densLPS.object.

  • psi1 : ⁠ ⁠estimated regression parameters for location (fixed effects, B-spline coefs for the J1 additive terms).

  • psi2 : ⁠ ⁠estimated regression parameters for dispersion (fixed effects, B-spline coefs for the J2 additive terms).

  • fixed.loc : ⁠ ⁠matrix with the estimated fixed effects (est,se,ci.low,ci.up) in the location sub-model.

  • fixed.disp : ⁠ ⁠matrix with the estimated fixed effects (est,se,ci.low,ci.up) in the dispersion sub-model.

  • mu : ⁠ ⁠n-vector with the fitted conditional mean.

  • sd : ⁠ ⁠n-vector with the fitted conditional standard deviation.

Additional elements:

  • data : ⁠ ⁠the original data frame used when calling the DALSM function.

  • phi : ⁠ ⁠estimated B-spline coefs for the log-hazard of the error distribution.

  • K.error : ⁠ ⁠number of B-splines used to approximate the log of the error hazard.

  • rmin, rmax : ⁠ ⁠minimum and maximum values for the support of the standardized error distribution.

  • knots.error : ⁠ ⁠equidistant knots on (rmin,rmax) used to specify the B-spline basis for the log of the error hazard.

  • bread.psi1, Sand.psi1, Cov.psi1: ⁠ ⁠estimated Variance-Covariance matrix for \psi_1.

  • U.psi1 : ⁠ ⁠gradient for \psi_1.

  • bread.psi2, Sand.psi2, Cov.psi2: ⁠ ⁠estimated Variance-Covariance matrix for \psi_2.

  • U.psi2 : ⁠ ⁠gradient for \psi_2.

  • U.psi : ⁠ ⁠gradient for \psi=(\psi_1,\psi_2).

  • Cov.psi : ⁠ ⁠variance-covariance for \psi=(\psi_1,\psi_2).

  • regr1 : ⁠ ⁠object generated by DesignFormula for the specified submodel for location.

  • regr2 : ⁠ ⁠object generated by DesignFormula for the specified submodel for dispersion.

  • res : ⁠ ⁠n-vector or nx2 matrix (if IC data) with the standardized residuals for the fitted model.

  • expctd.res : ⁠ ⁠n-vector with observed standardized residual for a non RC unit, or their expected value if right-censored.

  • REML : ⁠ ⁠logical indicating whether REML estimation was performed.

  • n : ⁠ ⁠the sample size.

  • n.uncensored : ⁠ ⁠number of non-censored response data.

  • event : ⁠ ⁠n-vector of event indicators (1: non right-censored ; 0: right censoring).

  • is.IC : ⁠ ⁠n-vector with interval censoring indicators.

  • n.IC : ⁠ ⁠number of interval-censored response data.

  • n.RC : ⁠ ⁠number of right-censored response data.

  • perc.obs : ⁠ ⁠percentage of exactly observed response data.

  • perc.IC : ⁠ ⁠percentage of interval-censored response data.

  • perc.RC : ⁠ ⁠percentage of right-censored response data.

  • cred.int : ⁠ ⁠nominal level for the reported credible intervals.

  • alpha : ⁠ ⁠user-specified \alpha with Bayesian (1-\alpha) credible intervals reported.

  • sandwich : ⁠ ⁠logical indicating if variance-covariance and standard errors computed using sandwich estimator in the NP case.

  • diag.only : ⁠ ⁠logical indicating if the correction to the Hessian under REML only concerns diagonal elements.

  • iter : ⁠ ⁠number of iterations.

  • elapsed.time : ⁠ ⁠time required by the model fitting procedure.

If there are additive terms in the location submodel:

  • K1 : ⁠ ⁠number of B-splines used to describe an additive term in the location submodel.

  • xi1 : ⁠ ⁠matrix with the selected log penalty parameters for the J1 additive terms in the location submodel (point estimate, se, ci.low, ci.up.

  • U.xi1 : ⁠ ⁠gradient for the log of the penalty parameters for the J1 additive terms in the location submodel.

  • U.lambda1 : ⁠ ⁠gradient for the penalty parameters for the J1 additive terms in the location submodel.

  • Cov.xi1 : ⁠ ⁠estimated Variance-Covariance matrix for the parameters involved in the J1 additive terms in the location submodel.

  • lambda1.min : ⁠ ⁠minimal value for the penalty parameters in the additive submodel for location.

  • lambda1 : ⁠ ⁠matrix with the selected penalty parameters for the J1 additive terms in the location submodel (point estimate, se, ci.low, ci.up).

  • ED1 : ⁠ ⁠matrix with the effective dimensions for each of the J1 additive terms in the location submodel (point estimate,ci.low,ci.up).

If there are additive terms in the dispersion submodel:

  • K2 : ⁠ ⁠number of B-splines used to describe an additive term in the dispersion submodel.

  • xi2 : ⁠ ⁠matrix with the selected log penalty parameters for the J2 additive terms in the dispersion submodel (point estimate, se, ci.low, ci.up).

  • U.xi2 : ⁠ ⁠gradient for the log of the penalty parameters for the J2 additive terms in the dispersion submodel.

  • U.lambda2 : ⁠ ⁠gradient for the penalty parameters for the J2 additive terms in the dispersion submodel.

  • Cov.xi2 : ⁠ ⁠estimated Variance-Covariance matrix for the parameters involved in the J2 additive terms in the dispersion submodel.

  • lambda2.min : ⁠ ⁠minimal value for the penalty parameters in the additive submodel for dispersion.

  • lambda2 : ⁠ ⁠matrix with the selected penalty parameters for the J2 additive terms in the dispersion submodel (point estimate, se, ci.low, ci.up).

  • ED2 : ⁠ ⁠matrix with the effective dimensions for each of the J2 additive terms in the dispersion submodel (point estimate,ci.low,ci.up).

Author(s)

Philippe Lambert p.lambert@uliege.be

References

Lambert, P. (2021). Fast Bayesian inference using Laplace approximations in nonparametric double additive location-scale models with right- and interval-censored data. Computational Statistics and Data Analysis, 161: 107250. <doi:10.1016/j.csda.2021.107250>

See Also

DALSM, print.DALSM, plot.DALSM, densityLPS, densLPS.object


DALSM documentation built on Oct. 2, 2023, 5:09 p.m.