Correlation of distance ratios and calibrated p-factors for Cepheids in the sample. The dashed line indicates the expected limit of p-factor (p = 1.5, see text for more details). The slope of the data at the point where the intercept passes through the origin, is 1.374, which is almost identical to − 0.186 × ⟨ log (P)⟩ + 1.550 = 1.372, with a mean period of ⟨log (P)⟩ = 0.955. Symbols are the same as in Fig. 1. The outlier with largest error bars is FF Aql. (See online edition for a color version.)