Effect of the environment on the SFR, 12 + log(O/H), sSFR, and D_n(4000) for SF galaxies. Local tidal strength affecting the central galaxies in the isolated pairs (circles) and triplets (stars) versus: 1) the SFR of the central galaxy, coloured by the SFR of the satellite galaxy (left upper panel); 2) the 12 + log(O/H) of the central galaxy, coloured by the 12 + log(O/H) of the satellite galaxy (right upper panel); 3) the sSFR of the central galaxy, coloured by the sSFR of the satellite galaxy (left lower panel); and 4) the D_n(4000) of the central galaxy, coloured by the D_n(4000) of the satellite galaxy (right upper panel). Squares and error bars represent the median trend (coloured according to the colour bar of each panel) and dispersion, respectively, in three bins of the local tidal strength parameter (Q_local ≤ −4, −4 < Q_local ≤ 0, and Q_local > 0). In the upper left on each panel we present a representative error, given by the median value of the error of the SFR (multiplied by 10 for better visualisation), 12 + log(O/H), sSFR, and D_n(4000) for central galaxies. The tidal strength parameter values from Argudo-Fernández et al. (2015) do not have an associated error.