**Xi'an's Og » R**, and kindly contributed to R-bloggers)

**G**illes Guillot from Technical University of Denmark taught a course based on our R book and he pointed out to me several typos in Chapter 5 of “** Introducing Monte Carlo Methods with R**”:

- p.137 second equation from bottom
should be

*[right, another victim of cut-and-paste]* - p. 138
**Example 5.7**denominator in the gradient should be 2*beta*[yes, the error actually occurs twice. And once again in the R code]* - p. 138 : First paragraph Not a typo but a lack of details: are the conditions on and necessary and sufficient?
*[indeed, they are sufficient]* - demo(Chapter.5) triggers an error message
*[true, the shortcut*max=TRUE*instead of*maximise=TRUE*in*optimise*does not work with R version 2.11.1]*

**I** checked the last item with the new version of R and got the following confirmation that optimise does not accept (any longer) the abbreviation of its arguments…

demo(Chapter.5)

————————Type <Return> to start :

> # Section 5.1, Numerical approximation

>

> ref=rcauchy(5001)> f=function(y){-sum(log(1+(x-y)^2))}

> mi=NULL

> for (i in 1:400){

+ x=ref[1:i]

+ aut=optimise(f,interval=c(-10,10),max=T)

+ mi=c(mi,aut$max)

+ }

Error in f(arg, …) : unused argument(s) (max = TRUE)> optimise(f,interval=c(-10,10),maximum=T)

$maximum

[1] -2.571893$objective

[1] -6.661338e-15

Filed under: Books, R, Statistics Tagged: birthday, Gilles Guillot, Introducing Monte Carlo Methods with R, optimise, R 2.11.1, R syntax, typo

**leave a comment**for the author, please follow the link and comment on their blog:

**Xi'an's Og » R**.

R-bloggers.com offers

**daily e-mail updates**about R news and tutorials on topics such as: visualization (ggplot2, Boxplots, maps, animation), programming (RStudio, Sweave, LaTeX, SQL, Eclipse, git, hadoop, Web Scraping) statistics (regression, PCA, time series, trading) and more...