### Stability accelerated studies (Arrhenius)

The Arrhenius approach is one way to estimate the stability of a reference material 
from the perspective of storage time or shelf life. As implemented in *eCerto*, 
the estimation is based on time series data of analytes at different temperature levels $T_i$.

$T_{min}$ is used as a reference point. For each $T_i$ a linear model is calculated, 
yielding potentially a slope $k_{\mathit{eff}}(T)$ indicative of analyte degradation. 
Combining all $k_{\mathit{eff}}$ allows to estimate the dependency of analyte stability 
on temperature and, consequently, the expected storage time at a given $T$.

The calculations are performed according to the recommendations for accelerated stability 
studies in ISO GUIDE 35:2017.

```{r child = 'stability_arrhenius_figS2.Rmd'}
```

```{r child = 'stability_arrhenius_tab1.Rmd'}
```

```{r child = 'stability_arrhenius_figS3.Rmd'}
```
