bootstrap estimates of corrected FA

This is the R code used to calculate FA (Left-Right) based on counted fin rays in right and left pectoral fins of all four samples (two from the Palos Verdes Peninsula: initial and survivors, and two from Catalina Island: initial and survivors). There are two independent counts and therefore two estimates of FA. The variance between these two estimates was used to correct for measurement error. The corrected FA estimate was then also corrected for the presence of directional asymmetry, and the samples were bootstrapped to give a statistically significant estimate of the relative size of FA between the two populations at the time of the two different sampling events.