R2

R2 is a code for:R2 is the IATA code for Orenburg AirlinesY-DNA Haplogroup R2R2 is an abbreviation or initialism which may represent:R2 is a name for the TSRTWO [tsur-too], a super computer located within Shaw Tower, Vancouver, BC Canada. Developed by Shaw Communications in conjunction with the SANAR projectR2-D2, a character from Star Wars films and booksany astromech droid in the Star Wars fictional universean abbreviation for BBC Radio 2, a British radio station, a conventional symbol for the coefficient of determination of a linear regression.R2 is a name for a plane i.e., the two-dimensional vector space of real numbers.The SEPTA Regional Rail R2 line in Philadelphia, PennsylvaniaR2 signalling, a family of telephony protocols for line and register signallingthe R-2 rocketR-2, an original mecha from Super Robot Wars series.R2, Redondos (Patricio Rey y sus Redonditos de Ricota), Argentine rock band.Release 2, or Second Release (for example Windows Server 2003 R2)Ryzom Ring, editor tool for the MMORPG RyzomR2, a non-LTR retrotransposable element which inserts into the ribosomal RNA genes in arthropods and other organismsDVD region code 2R2 or R² is the abbreviated name for Switched-On Schoolhouse R²
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Square of the correlation coefficient. The proportion of the variability in one series that can be explained by the variability of one or more other series in context of regression. A measure of the quality of fit. 100% R-square means perfect predictability.