What does it mean to "have a mantainer"? Is he a third party? Is he an individual developer and you can install whose package on your risk? Are the package created by maintainers not tested?
Anyway, I wrote him. I'm waiting for response. Regards Il 23/Nov/2016 22:21, "peter dalgaard" <pda...@gmail.com> ha scritto: > Notice that this relates to an R _package_, which has a maintainer. You > cannot expect general R users or developers to know about the details of > the package. It doesn't look like there is dcoumentation beyond the help > pages, so you may need to contact the maintainer or study the actual code. > > -pd > > > On 23 Nov 2016, at 17:08 , Luke Skywalker <mattere...@gmail.com> wrote: > > > > Good evening, > > > > I'm encountering a different kind of discretization with respect to the > > 1997 Liu and Setiono's one descripted in their papers, using Chi2 > algorithm > > for feature selection with discretization. > > > > As stated in R documentation (discretization - R (from CRAN) > > <https://cran.r-project.org/web/packages/discretization/ > discretization.pdf>), > > R package discretizion offers the function Chi2, which comes to life in > the > > following papers: > > > > Liu, H. and Setiono, R. (1995). Chi2: Feature selection and > discretization > > of numeric attributes, Tools with Artificial Intelligence, 388–391. > > > > Liu, H. and Setiono, R. (1997). Feature selection and discretization, > IEEE > > transactions on knowledge and data engineering, Vol.9, no.4, 642–645. > > > > I wrote the following R programming language code, in which I have set > > alpha and delta equal to the ones set in the papers above. Finally, the > > following code prints out the discretized dataframe. I used Iris > dataframe, > > as in one of the examples in the two papers. The first paper above states > > that alfa = 0.5 and delta = 5%, and that "the originally odd numbered > data > > are selected for training (75 patterns) and rest for testing (75 > > patterns)". With this asset, Sepal attributes should be removed. > > > > library(discretization) > > data(iris) > > df1 <- iris[FALSE,]for(i in 1:nrow(iris)){ > > if(i %% 2 != 0){ > > df1 <- rbind(df1, iris[i,]) > > }} > > chi2(df1, alp=0.5, del=0.05)$Disc.data > > > > The point is that, observing the dataframe printed out by the last > > instruction, you can see that no attribute is removed. The discretized > data > > frame still have 4 attributes discretized: if I correctly understood the > > above papers, Sepal Length and Sepal Width should have been both > > discretized in just one interval by Chi2 algorithm. > > > > I have posted a question here: http://stats.stackexchange.com/questions/ > > 247499/why-does-not-r-chi2-algorithm-discretize-in-the- > > same-manner-as-in-the-paper-by-l?noredirect=1#comment470974_247499. > > > > > > Moreover, it's really hard to understand the cut points that Chi2 > algorithm > > implemented in R makes. For example: > > > > res <- chi2(iris, 0.5, 0.05) > > > > cut(iris$Sepal.Length, res$cutp, labels=FALSE) is different from > > res$Disc.data$Sepal.Length > > > > Help me understand, please > > > > Best regards > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide http://www.R-project.org/ > posting-guide.html > > and provide commented, minimal, self-contained, reproducible code. > > -- > Peter Dalgaard, Professor, > Center for Statistics, Copenhagen Business School > Solbjerg Plads 3, 2000 Frederiksberg, Denmark > Phone: (+45)38153501 > Office: A 4.23 > Email: pd....@cbs.dk Priv: pda...@gmail.com > > > > > > > > > > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.