Start a multistart method

2 files changed, 26 insertions, 0 deletions

diff --git a/NEWS.md b/NEWS.md
index 4cffcb81..0738d54a 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,7 @@
 # mkin 1.1.2
 
+- 'R/multistart.R': New method for testing multiple start parameters for hierarchical model fits.
+
 - 'R/mhmkin.R': New method for performing multiple hierarchical mkin fits in one function call, optionally in parallel.
 
 - 'R/saem.R': Implement and test saemix transformations for FOMC and HS. Also, error out if saemix transformations are requested but not supported.
diff --git a/R/multistart.R b/R/multistart.R
new file mode 100644
index 00000000..db482cc4
--- /dev/null
+++ b/R/multistart.R
@@ -0,0 +1,24 @@
+#' Perform a hierarchical model fit with multiple starting values
+#'
+#' The purpose of this method is to check if a certain algorithm for fitting
+#' nonlinear hierarchical models (also known as nonlinear mixed-effects models)
+#' will reliably yield results that are sufficiently similar to each other, if
+#' started with a certain range of reasonable starting parameters. It is
+#' inspired by the article on practical identifiabiliy in the frame of nonlinear
+#' mixed-effects models by Duchesne et al (2021).
+#'
+#' @references Duchesne R, Guillemin A, Gandrillon O, Crauste F. Practical
+#' identifiability in the frame of nonlinear mixed effects models: the example
+#' of the in vitro erythropoiesis. BMC Bioinformatics. 2021 Oct 4;22(1):478.
+#' doi: 10.1186/s12859-021-04373-4.
+#' @export
+multistart <- function(object, n = 50, ...)
+{
+  UseMethod("multistart", object)
+}
+
+#' @rdname multistart
+#' @export
+multistart.saem.mmkin <- function(object, n = 50, ...) {
+  
+}