# sbiofitmixed

Fit nonlinear mixed-effects model (requires Statistics and Machine Learning Toolbox software)

## Syntax

## Description

performs nonlinear mixed-effects estimation using the SimBiology`fitResults`

= sbiofitmixed(`sm`

,`grpData`

,`ResponseMap`

,`covEstiminfo`

)^{®} model `sm`

and returns a
`NLMEResults`

object `fitResults`

.

`grpData`

is a ```
groupedData
object
```

specifying the data to fit.
`ResponseMap`

defines the mapping between the model
components and response data in `grpData`

.
`covEstiminfo`

is a `CovariateModel object`

or an
array of `estimatedInfo`

objects that defines the parameters to
be estimated.

If the model contains active doses and variants, they are applied during the simulation.

uses the dosing information specified by a matrix of SimBiology dose objects
`fitResults`

= sbiofitmixed(`sm`

,`grpData`

,`ResponseMap`

,`covEstiminfo`

,`dosing`

)`dosing`

instead of using the active doses of the model
`sm`

if there are any.

uses the estimation function specified by `fitResults`

= sbiofitmixed(`sm`

,`grpData`

,`ResponseMap`

,`covEstiminfo`

,`dosing`

,`functionName`

)`functionName`

that
must be either `'nlmefit'`

or
`'nlmefitsa'`

.

uses the additional options specified by `fitResults`

= sbiofitmixed(`sm`

,`grpData`

,`ResponseMap`

,`covEstiminfo`

,`dosing`

,`functionName`

,`opt`

)`opt`

for the
estimation function `functionName`

.

applies variant objects specified as `fitResults`

= sbiofitmixed(`sm`

,`grpData`

,`ResponseMap`

,`covEstiminfo`

,`dosing`

,`functionName`

,`opt`

,`variants`

)`variants`

instead of
using any active variants of the model.

uses additional options specified by one or more name-value arguments.`fitResults`

= sbiofitmixed(___,`Name,Value`

)

`[`

returns a vector of results objects `fitResults`

,`simDataI`

,`simDataP`

]
= sbiofitmixed(_)`fitResults`

,
vector of simulation results `simDataI`

using individual-specific
parameter estimates, and vector of simulation results `simDataP`

using
population parameter estimates.

**Note**

`sbiofitmixed`

unifies`sbionlmefit`

and`sbionlmefitsa`

estimation functions. Use`sbiofitmixed`

to perform nonlinear mixed-effects modeling and estimation.`sbiofitmixed`

simulates the model using a`SimFunction object`

, which automatically accelerates simulations by default. Hence it is not necessary to run`sbioaccelerate`

before you call`sbiofitmixed`

.

## Examples

## Input Arguments

## Output Arguments

## References

[1] Grasela Jr, T.H., Donn, S.M. (1985) Neonatal population pharmacokinetics of phenobarbital derived from routine clinical data. Dev Pharmacol Ther. 8(6), 374–83.

## Extended Capabilities

## See Also

`sbiofit`

| `nlmefit`

(Statistics and Machine Learning Toolbox) | `nlmefitsa`

(Statistics and Machine Learning Toolbox) | `groupedData`

| `EstimatedInfo object`

| `NLMEResults object`

| `sbiofitstatusplot`

| `CovariateModel object`

### Topics

- Modeling the Population Pharmacokinetics of Phenobarbital in Neonates
- What Is a Nonlinear Mixed-Effects Model?
- Nonlinear Mixed-Effects Modeling Workflow
- Specify a Covariate Model
- Specify an Error Model
- Maximum Likelihood Estimation
- Obtain the Fitting Status
- Supported Methods for Parameter Estimation in SimBiology
- Progress Plot
- Importing Data — Supported Files and Data Types
- Create Data File with SimBiology Definitions

**Introduced in R2014a**