search for: tsiatis

...al submodel to be fitted and the type of the numerical integration technique; available options are: * "ph-GH": the time-dependent version of a proportional hazards model with unspecified baseline hazard function. This option corresponds to the joint model proposed by Wulfsohn and Tsiatis, Biometrics, 1997. * "weibull-GH": the Weibull model under the accelerated failure time formulation. * "ch-GH" and "ch-Laplace": an additive log cumulative hazard model, in which the log cumulative baseline hazard is approximated using B-splines. For &qu...

...al submodel to be fitted and the type of the numerical integration technique; available options are: * "ph-GH": the time-dependent version of a proportional hazards model with unspecified baseline hazard function. This option corresponds to the joint model proposed by Wulfsohn and Tsiatis, Biometrics, 1997. * "weibull-GH": the Weibull model under the accelerated failure time formulation. * "ch-GH" and "ch-Laplace": an additive log cumulative hazard model, in which the log cumulative baseline hazard is approximated using B-splines. For &qu...

...d by argument 'survMod'). * In addition, argument 'param' of jointModelBayes() specifies the association structure between the longitudinal and survival processes; available options are: - "td-value" which is the classic joint model formulation used in Wulfsohn and Tsiatis (1997); - "td-extra" which is a user-defined, possibly time-dependent, term based on the specification of the 'extraForm' argument of jointModelBayes(). This could be used to include terms, such as the time-dependent slope (i.e., the derivative of the subject-specific lin...

...d by argument 'survMod'). * In addition, argument 'param' of jointModelBayes() specifies the association structure between the longitudinal and survival processes; available options are: - "td-value" which is the classic joint model formulation used in Wulfsohn and Tsiatis (1997); - "td-extra" which is a user-defined, possibly time-dependent, term based on the specification of the 'extraForm' argument of jointModelBayes(). This could be used to include terms, such as the time-dependent slope (i.e., the derivative of the subject-specific lin...

Dear R users, I know one way to see the code for a hidden function, say function_x, is using default.function_x (e.g. summary.default). But how can I see the code for imported packages that have no namespace (in this case Design)? Many Thanks Eleni

hi, folks, how have you gone about reporting a p-value from a test when the returned value from a test (in this case a rank-sum test) is numerically equal to 0 according to the machine? the next lowest value greater than zero that is distinct from zero on the machine is likely algorithm-dependent (the algorithm of the test itself), but without knowing the explicit steps of the algorithm

...tial trials There are two main functions, (1) GrpSeqBnds: computes group sequential stopping boundaries for interim analysis of a sequential trial based upon a normally distributed test statistic. This can be done via the Lan-Demets procedure with Obrien-Fleming, Pocock or Wang-Tsiatis spending. This can also be done via boundaries created to correspond with the stochastic curtailment procedure. (2) PwrGSD (same as the package name) which computes operating characteristics such as power, expected duration, weighted avergage relative risks at the boun...

...tial trials There are two main functions, (1) GrpSeqBnds: computes group sequential stopping boundaries for interim analysis of a sequential trial based upon a normally distributed test statistic. This can be done via the Lan-Demets procedure with Obrien-Fleming, Pocock or Wang-Tsiatis spending. This can also be done via boundaries created to correspond with the stochastic curtailment procedure. (2) PwrGSD (same as the package name) which computes operating characteristics such as power, expected duration, weighted avergage relative risks at the boun...