Notes. Strong correlations or strong anti-correlations are marked in bold. q is the exponent of the dust-grain size-distribution, is the minimum radius of aligned silicates, is the mean radius of aligned silicates. Samples are defined as follows. – S-sample: single-cloud sight-lines (Table 1). HD 210121 is excluded. For the correlation studies with λ_max we consider only 6 stars with λ_max ≤ 700 nm. M-sample: multiple-cloud sight-lines with 24 stars as of Table 1. – M_SP -sample: stars belonging to the M-sample that have the ratio p_max∕A_V in the observed range of the S-sample, and either k_P or λ_max also in the range of the S-sample. The M_SP-sample has a narrower range in the observing parameters than the S-sample. – M_S -sample: M-sample that are in the observed range of the S-sample either in k_P or λ_max. – L-sample: LIPS objects that are not single-cloud cases, including 51 stars. – L_SP -sample: L-sample that are in the observed range of the S sample in p_max∕A_V and either k_P or λ_max.