User's guide to SMATR : standardised major axis tests and routines version 2.0, copyright 2006

SMATR is a freeware program used for fitting bivariate lines to data and for making inferences about such lines. A line can be fitted using standardised major axis (SMA), major axis (MA) or ordinary least squares regression (OLS) techniques. The routines available in SMATR allow you to: - fit lines to groups of data using SMA, MA or OLS methods - construct exact confidence intervals around slope and intercept parameters and compare these to hypothesised values - test for a common a common slope or elevation among lines fitted to several groups - test for a shift along a common axis among lines fitted to several groups - fit lines forced through the origin (appropriate for phylogenetic analyses) - incorporate measurement error into parameter estimates. Details about the use of these statistics and about the underlying formulas and their validation can be found in: Warton, DI, IJ Wright, DS Falster, and M Westoby (2006) Bivariate line-fitting methods for allometry.