Fig. 7: Modelling of the weighted cosine systematicity (sys_cos_w) between Shanghai Shiqu and the other local dialectal varieties.

Butterfly-scatter-violin-box plots are used to show the sys_cos_w values (multiplied by 1000 and natural log-transformed) for different time-slices (old and new) and mapping directions (left: Shiqu→SH local, right: SH local→Shiqu). Each translucent point on the scatter plots represents a single mapping, with its horizontal coordinate representing the sys_cos_w value (the vertical coordinate is jittered for visualisation purposes). The coloured violin shapes indicate the probability density of the sys_cos_w values, while the box plots represent the range, quartiles, median and odd values, annotated with means (yellow for Shiqu→SH loca and red for SH local→Shiqu). Based on the LME results, significance codes are marked on conditions with positive effects, with main effects annotated on the grey cross lines at the centre, and interaction effects in the panel related to the interaction term. Blue shades are added to cells representing positive main effects for the new varieties, and red shades are added to cells representing positive main effects for the new varieties. In addition, blue shades on the right corner of cells represent positive interaction effects for the mapping SH local→Shiqu, and red shades represent negative interaction effects. The subplots are vertically arranged according to the pairs of linguistic varieties, and horizontally according to the phonemic units.