Instantiate a new error model.
errorModel(var = "CONC", add = 0, prop = 0, type = NULL)
| var | the related variable name |
|---|---|
| add | additive residual error, as stdev |
| prop | proportional residual error, as stdev |
| type | type of error: constant, proportional, combined1, combined2, exponential or NULL to auto-detect. A combination of additive and proportional always assumes 'combined2'. |
Please note that convention differ between modeling software. While NONMEM would always code a combined additive/proportional model as `W=SQRT( SIGMA(1)**2 + SIGMA(2)**2 * IPRED**2 )`, Monolix uses a default of `CONC = Cc + (a + b*Cc)*e`. TDMore uses the NONMEM convention by default.