```r
m.L2.DFOP <- mkinfit("DFOP", FOCUS_2006_L2_mkin, quiet = TRUE)
plot(m.L2.DFOP, show_residuals = TRUE, show_errmin = TRUE,
     main = "FOCUS L2 - DFOP")
```

<img src="FOCUS_L_files/figure-html/unnamed-chunk-10-1.png" width="672" />

```r
summary(m.L2.DFOP, data = FALSE)
```

```
## mkin version:    0.9.44.9000 
## R version:       3.3.1 
## Date of fit:     Wed Oct 26 23:18:13 2016 
## Date of summary: Wed Oct 26 23:18:14 2016 
## 
## Equations:
## d_parent = - ((k1 * g * exp(-k1 * time) + k2 * (1 - g) * exp(-k2 *
##            time)) / (g * exp(-k1 * time) + (1 - g) * exp(-k2 *
##            time))) * parent
## 
## Model predictions using solution type analytical 
## 
## Fitted with method Port using 336 model solutions performed in 0.803 s
## 
## Weighting: none
## 
## Starting values for parameters to be optimised:
##          value   type
## parent_0 93.95  state
## k1        0.10 deparm
## k2        0.01 deparm
## g         0.50 deparm
## 
## Starting values for the transformed parameters actually optimised:
##              value lower upper
## parent_0 93.950000  -Inf   Inf
## log_k1   -2.302585  -Inf   Inf
## log_k2   -4.605170  -Inf   Inf
## g_ilr     0.000000  -Inf   Inf
## 
## Fixed parameter values:
## None
## 
## Optimised, transformed parameters with symmetric confidence intervals:
##          Estimate Std. Error Lower Upper
## parent_0  93.9500         NA    NA    NA
## log_k1     3.1370         NA    NA    NA
## log_k2    -1.0880         NA    NA    NA
## g_ilr     -0.2821         NA    NA    NA
## 
## Parameter correlation:
```

```
## Warning in print.summary.mkinfit(x): Could not estimate covariance matrix; singular system:
```

```
## Could not estimate covariance matrix; singular system:
## 
## Residual standard error: 1.732 on 8 degrees of freedom
## 
## Backtransformed parameters:
## Confidence intervals for internally transformed parameters are asymmetric.
## t-test (unrealistically) based on the assumption of normal distribution
## for estimators of untransformed parameters.
##          Estimate t value Pr(>t) Lower Upper
## parent_0  93.9500      NA     NA    NA    NA
## k1        23.0400      NA     NA    NA    NA
## k2         0.3369      NA     NA    NA    NA
## g          0.4016      NA     NA    NA    NA
## 
## Chi2 error levels in percent:
##          err.min n.optim df
## All data    2.53       4  2
## parent      2.53       4  2
## 
## Estimated disappearance times:
##          DT50  DT90 DT50_k1 DT50_k2
## parent 0.5335 5.311 0.03009   2.058
```