We then standardized all response and explanatory variables before the analyses using z-scores (i.e. scaling data to mean 0, standard deviation (sd) 1), to allow us to compare coefficients between forest attributes and ecosystem services.
To assess the relative effect size for these explanatory variables, the response and explanatory variables were standardized such that the mean of each variable was 0 with a standard deviation of 1.
Figure 2 and Table 5 present the SEM modeling output, as well as the estimated coefficients for exogenous and endogenous variables, statistical significance, and standardized total effects among the explanatory variables.
All explanatory variables were standardized (zero mean, unit variance; Table A3) to facilitate the interpretation of their relative influence on mean laying dates.
As a randomized trial, the study included some explanatory features (e.g., standardized follow-up surveys administered by study personnel); however, several aspects of the study were highly pragmatic.
To investigate the link between adherence to HAART and mortality, the values of the moving averages and standardized variances of adherence were considered as explanatory variables in a time-dependent Cox model [ 20– 20].
Alternative models were fitted where whole blood Pb, plasma Pb and bone Pb were included as explanatory variables instead of the Plasma/Blood Pb ratio, these latter models included standardized independent variables, and the estimated IRRs are per one standard-deviation change in the explanatory variable.
Second, the authors of the primary studies used different discrete choice models and did not provide standardized marginal effects with respect to changes in the explanatory variables.
Simulations performed by us suggest that the problem could be solved by completely standardizing the potentially problematic explanatory variable.
The explanatory effect of minority background on emotional symptoms was only 3%, which is small but significant (See standardized regression coefficient of ethnic status, β = -.16 in Table 3 and square it for information about its contribution to emotional problems).
