Direct error model fitting works

- No IRLS required
- Removed optimization algorithms other than Port
- Removed the dependency on FME
- Fitting the error model 'obs' is much faster for the FOCUS_2006_D
  dataset and the FOMC_SFO model (1 second versus 3.4 seconds)
- Vignettes build slower. Compiled models needs 3 minutes instead of 1.5
- For other vignettes, the trend is less clear. Some fits are faster,
  even for error_model = "const". FOCUS_Z is faster (34.9 s versus
  44.1 s)
- Standard errors and confidence intervals are slightly smaller
- Removed code for plotting during the fit, as I hardly ever used it
- Merged the two cost functions (using transformed and untransformed
  parameters) into one log-likelihood function

1 files changed, 0 insertions, 9 deletions

diff --git a/build.log b/build.log
index 6831459d..976d27d4 100644
--- a/build.log
+++ b/build.log
@@ -1,10 +1 @@
 * checking for file ‘./DESCRIPTION’ ... OK
-* preparing ‘mkin’:
-* checking DESCRIPTION meta-information ... OK
-* installing the package to build vignettes
-* creating vignettes ... OK
-* checking for LF line-endings in source and make files and shell scripts
-* checking for empty or unneeded directories
-* looking to see if a ‘data/datalist’ file should be added
-* building ‘mkin_0.9.48.1.tar.gz’
-