# Errata & Notes

## Errata

**Page 86, Footnote 7**– “Ager C” should be “Ager B”.**Page 207, Equation for \(\hat{Z}\)**– \(N\) should be \(n\) in the denominator. Thus, the new equation should be

\[\hat{Z} = -log(\hat{S}) - \frac{(n-1)(n-2)}{n(T+1)(n+T-1)} \]

## Post-Production Changes

**Throughout**– I have removed`filterD()`

from`FSA`

. Please see this fishR post for how to accomplish the same effect using functions from`dplyr`

.**Section 2.4**– The maintainers of`tidyr`

suggest using`pivot_longer()`

instead of`gather()`

and`pivot_wider()`

instead of`spread()`

, though`gather()`

and`spread()`

still work as shown in the book.**Section 4.2**– I have dramatically changed the age-bias plot that is produced by`plot()`

with an object saved from`ageBias()`

. This change is described in the documentation and examples for`ageBias()`

. The plots shown in the book can largely still be produced with`plotAB()`

(see its documentation here). Also see this fishR post for a description of constructing an age-bias plot using`ggplot2`

.**Section 4.4**– I have changed the information that is returned from`agePrecision()`

. All of the information shown in the book is still provided; however, other information (e.g., average standard deviation and mean absolute deviation) are now also returned. The output is documented in the documentation for`agePrecision()`

.**Sections 7.3.3, 8.3.2.1, 12.3.6, and 13.2.2**–`residPlot()`

has been removed from the`FSA`

package. Other methods for constructing residuals plots are discussed in this fishR post.**Sections 12.3.1 and 13.1**– The dynamic plots described for finding starting values for a von Bertalanffy growth function and the stock-recruitment functions (i.e., nonlinear regressions) have been removed from`vbStarts()`

and`srStarts()`

, because of the difficulty of maintaining a package that requires the`tcltk`

package. These functionalities are now in the`FSAsims`

package, but it can also largely be replicated with the`fixed=`

arguments to`vbStarts()`

and`srStarts()`

. Use of`fixed=`

in`srStarts()`

is demonstrated in this blog post.