Fig. 7

A The GLMM model estimates for the mobile accuracy tests including their confidence intervals with 3.872 as reference level (intercept). The model included scaled numerical explanatory variables (sc) and were modeled on a gamma distribution with a log-link. The estimates are back transformed to the original scale in meters. Purple suggests a negative effect and green a positive effect. Furthermore, abrogated stars indicate the strength of evidence. And B the prediction plot for terrain ruggedness index (TRI) with the predicted GPS accuracy in meters. The black line represents the prediction with the gray ribbons as the standard error. The gray points are the original observations (n = 92)