GeDS-class {GeDS}

GeDS Class

Description

A fitted GeDS object returned by the functions NGeDS or GGeDS inheriting the methods from class "GeDS". Methods for functions coef, knots, print, predict, plot, and lines are available.

Slots

Type

Character string indicating the type of the regression performed. One of "LM - Univ", "LM - Biv" or "GLM - Univ" corresponding to the Normal univariate GeDS, the Normal bivariate GeDS performed by NGeDS and the generalized (GNM-GLM) univariate GeDS performed by GGeDS.

Linear.Knots

Vector containing the locations of the knots of the second order GeDS spline fit generated at stage A.

Quadratic.Knots

Vector containing the locations of the knots of the third order GeDS spline fitted in stage B.

Cubic.knots

Vector containing the locations of the knots of the fourth order GeDS spline fitted in stage B.

Dev.Linear

Deviance of the second order GeD spline fit of stage A.

Dev.Quadratic

Deviance of the third order GeD spline fit of stage B.

Dev.Cubic

Deviance of the fourth order GeD spline fit of stage B.

RSS

Vector containing the deviances of the second order spline fits computed at each GeDS iteration in stage A.

Linear

List containing the results from running a SplineReg function used to fit the second order spline of stage A.

Quadratic

List containing the results from running SplineReg function used to fit the third order spline in stage B.

Cubic

List containing the results from a SplineReg function used to fit the fourth order spline in stage B.

Stored

Matrix containing the knot locations estimated at each step of stage A.

Args

List containing the input arguments passed on the Fitters functions.

Call

call to the Fitters functions.

Nintknots

The final number of internal knots of the second order GeD spline fit of stage A.

iters

Number of iterations performed in stage A of the GeDS fitting procedure.

Guesses

Initial values for the coefficients used at each iteration of stage A in order to estimate the spline coefficients. Since the initial values are used only in the IRLS procedure, this slot is empty if the object is not created by GGeDS or GenUnivariateFitter functions.

Coefficients

Matrix containing the fitted coefficients of the GeD spline regression component and the parametric component at each iteration of stage A.

deviance

Vector containing the deviances of the second order spline fits computed at each IRLS iteration in stage A. Since the IRLS procedure is used only in GGeDS or GenUnivariateFitter, this slot is empty if the object is not created by one of these functions.

iterIrls

Vector containing the numbers of IRLS iterations for all iterations of stage A cumulatively. Since the IRLS procedure is used only in GGeDS or GenUnivariateFitter, this slot is empty if the object is not created by one of these functions.

stopinfo

List of values providing information related to the stopping rule of stage A of GeDS. The sub-slots of stopinfo are phis, phis_star, oldintc and oldslp. The sub-slot phis is a vector containing the values of the ratios of deviances (or the difference of deviances if the LR stopping rule was chosen). The sub-slots phis_star, oldintc and oldslp are non-empty slots if the SR stopping rule was chosen. They contain respectively \hat{\phi}_{\kappa}, \hat{\gamma}_0 and \hat{\gamma}_1 computed at each iteration of stage A, see Dimitrova et al. (2023).

Formula

The model formula.

extcall

call to the NGeDS or GGeDS functions.

terms

terms object containing information on the model frame.

References

Dimitrova, D. S., Kaishev, V. K., Lattuada, A. and Verrall, R. J. (2023). Geometrically designed variable knot splines in generalized (non-)linear models. Applied Mathematics and Computation, 436.
DOI: doi:10.1016/j.amc.2022.127493