“…The single‐station sigma was introduced to detect and avoid double counting those components of ground motion variability at a specific station that are repeatable from different sources (Atkinson, ; Kuehn & Scherbaum, , ; Morikawa et al, ; Rodriguez‐Marek et al, ; Rodriguez‐Marek, Montalva, Cotton, & Bonilla, ). To obtain the single‐station standard deviation, either we need a station‐specific data set (Atkinson, ; Chen & Faccioli, ; Lin et al, ; Morikawa et al, ; Rodriguez‐Marek et al, ; Zafarani & Soghrat, ) or we propose a nonergodic model (Kuehn & Scherbaum, , ). With respect to the ergodic assumption, there is no difference in ground motion variability observed in a global data set and the one at a specific station source.…”