Parameter estimates, variance-covariance components, and fit statistics of the mixed-effects model (Eq 5).

<p>[<i>R</i>^<i>2</i>_<i>adj</i>: adjusted coefficient determination; <i>RMSE</i>: root mean squared errors; <i>AIC</i>: Akaike’s information criterion; <i>b</i>_<i>1</i>, <i>b</i>_<i>2</i>,<i>…</i>,<i>b</i>_<i>6</i>: fixed parameters; <i>u</i>_<i>j1</i>, <i>u</i>_<i>j2</i> = random effects parameters; <i>σ</i>^<i>2</i>_<i>uj1</i>: variance of <i>u</i>_<i>j1</i>; <i>σ</i>^<i>2</i>_<i>uj2</i>: variance of <i>u</i>_<i>j2</i>; <i>σ</i>^<i>2</i>: variance according to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0186394#pone.0186394.e010" target="_blank">Eq 7</a>; <i>φ</i> = parameter of a power variance function (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0186394#pone.0186394.e011" target="_blank">Eq 8</a>); standard errors are given in the parenthesis].