R-value or rvalue may refer to: R-value (insulation) in building engineering, the efficiency of insulation of a house R-value (soils) in geotechnical engineering, the stability of soils and aggregates for pavement construction R-factor (crystallography), a measure of the agreement between the crystallographic model and the diffraction data R0 or R number, the basic reproduction number in epidemiology In computer science, a pure value which cannot be assigned to In statistics, the Pearson product-moment correlation coefficient, or simply correlation coefficient In solid mechanics, the Lankford coefficient See also L-value (disambiguation) R rating (disambiguation) R-factor, a plasmid that codes for antibiotic resistance