News

2013-10-25

SMPS 2014 Website Launched

7th International Conference "Soft Methods in Probability and Statistics" - SMPS 2014 website has launched.
2013-08-20 software

stringi_0.1-9 Now Available

stringi is THE R package for correct, fast, and simple string processing in each locale and native charset. Another alpha release (for testing purposes) can be automatically downloaded by calling in R:

source('http://stringi.rexamine.com/install.R') # Message from the future: the link is outdated

The auto-installer gives access to a Windows i386/x64 build for R 3.0 or allows building the package from sources on Linux or MacOS.

UPDATE@2013-11-13. Version 0.1-10 now available. Includes some bugfixes. Moreover, on Linux/UNIX ./configure now first tries to read build settings from pkg-config (as the usage of icu-config is deprecated).

UPDATE@2013-11-16. Version 0.1-11 now available. ICU4C is now statically linked on Windows, so there is no need to download any additional libraries – a binary version is now available for R 2.15.X and 3.0.X. Moreover, on platforms where packages are built from sources, the ./configure script now tries to find ICU4C automagically.

UPDATE@2013-11-21. Build of version 0.1-11 now available for OS X (x64) and R 3.0. Have fun.

UPDATE@2014-02-15. Version 0.1-20 (source and Win_build only) now available. Now it does not depend on any external ICU library (the library source code is included).

2013-07-05 software

stringi: THE String Processing Package for R **alpha release**

stringi is THE R package for correct, fast, and simple string processing in each locale and native charset. ICU API bindings offer a rich variety of platform-, system-locale-, and native-charset-independent functions known from other programming languages, like Java, Perl, Python and PHP.

The alpha release (for testing purposes) is available here (includes Windows i386/x64 build for R 3.0). Any comments and suggestions are welcome!

2013-07-02 new paper

"Scientific Impact Assessment Cannot Be Fair" Accepted for Publication

My paper "Scientific Impact Assessment Cannot Be Fair" has just been accepted for publication in Journal of Informetrics. Bibliography entry:

Gagolewski M., Scientific Impact Assessment Cannot be Fair, Journal of Informetrics 7(4), 2013, pp. 792-802.

Abstract: In this paper we deal with the problem of aggregating numeric sequences of arbitrary length that represent e.g. citation records of scientists. Impact functions are the aggregation operators that express as a single number not only the quality of individual publications, but also their author's productivity.
We examine some fundamental properties of these aggregation tools. It turns out that each impact function which always gives indisputable valuations must necessarily be trivial. Moreover, it is shown that for any set of citation records in which none is dominated by the other, we may construct an impact function that gives any a priori-established authors' ordering. Theoretically then, there is considerable room for manipulation in the hands of decision makers.
We also discuss the differences between the impact function-based and the multicriteria decision making-based approach to scientific quality management, and study how the introduction of new properties of impact functions affects the assessment process. We argue that simple mathematical tools like the h- or g-index (as well asother bibliometric impact indices) may not necessarily be a good choice when it comes to assess scientific achievements.
2013-06-23 software

FuzzyNumbers-0.3-1 Released

A new version of the FuzzyNumbers package for R has just been submitted to the CRAN archive.
** FuzzyNumbers Package CHANGELOG **

***************************************************************************

0.3-1 /2013-06-23/

* piecewiseLinearApproximation() - general case (any knot.n)
for method="NearestEuclidean" now available.
Thus, method="ApproximateNearestEuclidean" is now deprecated.

* New binary arithmetic operators, especially
for PiecewiseLinearFuzzyNumbers: +, -, *, /

* New method: fapply() - applies a function on a PLFN
using the extension principle

* New methods: as.character(); also used by show().
This function also allows to generate LaTeX code defining the FN
(toLaTeX arg thanks to Jan Caha).

* as.FuzzyNumber(), as.TriangularFuzzyNumber(), as.PowerFuzzyNumber(), and
as.PiecewiseLinearFuzzyNumber() are now S4 methods,
and can be called on objects of type numeric, as well as on
various FNs

* piecewiseLinearApproximation() and as.PiecewiseLinearFuzzyNumber()
argument `knot.alpha` now defaults to equally distributed knots
(via given `knot.n`). If `knot.n` is missing, then it is guessed
from `knot.alpha`.

* PiecewiseLinearFuzzyNumber() now accepts missing `a1`, `a2`, `a3`, `a4`,
and `knot.left`, `knot.right` of length `knot.n`+2. Moreover, if `knot.n`
is not given, then it is guessed from length(knot.left).
If `knot.alpha` is missing, then the knots will be equally distributed
on the interval [0,1].

* alphacut() now always returns a named two-column matrix.
evaluate() returns a named vector.

* New function: TriangularFuzzyNumber - returns a TrapezoidalFuzzyNumber.

* Function renamed: convert.side to convertSide, convert.alpha
to convertAlpha, approx.invert to approxInvert

* Added a call to setGeneric("plot", function(x, y, ...) ...
to avoid a warning on install

* The FuzzyNumbers Tutorial has been properly included
as the package's vignette

* DiscontinuousFuzzyNumber class has been marked as **EXPERIMENTAL**
in the manual

* Man pages extensively updated

* FuzzyNumbers devel repo moved to GitHub
2013-06-05 new book

Book on R in Press

My book Programowanie w języku R. Analiza danych, obliczenia, symulacje (R Programming: Data Analysis, Computing & Simulation) has been accepted for publication by Wydawnictwo Naukowe PWN. It will appear on February, 2014.
2013-04-03 award

START 2013 Scholarship

I've been granted the Foundation for Polish Science (FNP) Scholarship for “young, talented researchers” ‐ START 2013 Program.
2013-04-02 new paper

AGOP'13: Two Papers Accepted

Our two papers has just been accepted for this year's AGOP Workshop. The proceedings will appear in Springer's Advances in Intelligent and Soft Computing Series.
  • Cena A., Gągolewski M., OM3: ordered maxitive, minitive, and modular aggregation operators – Part I: Axiomatic analysis under arity-dependence, In: Bustince H. et al (Eds.), Aggregation Functions in Theory and in Practise (AISC 228), Springer-Verlag, Heidelberg, 2013, pp. 93-103.
    Abstract: Recently, a very interesting relation between symmetric minitive, maxitive, and modular aggregation operators has been shown. It turns out that the intersection between any pair of the mentioned classes is the same. This result introduces what we here propose to call the OM3 operators. In the first part of our contribution on the analysis of the OM3 operators we study some properties that may be useful when aggregating input vectors of varying lengths. In Part II we will perform a thorough simulation study of the impact of input vectors' calibration on the aggregation results.
  • Cena A., Gągolewski M., OM3: ordered maxitive, minitive, and modular aggregation operators – Part II: A simulation study, In: Bustince H. et al (Eds.), Aggregation Functions in Theory and in Practise (AISC 228), Springer-Verlag, Heidelberg, 2013, pp. 105-115.
    Abstract: This article is a second part of the contribution on the analysis of the recently-proposed class of symmetric maxitive, minitive and modular aggregation operators. Recent results (Gagolewski, Mesiar, 2012) indicated some unstable behavior of the generalized h-index, which is a particular instance of OM3, in case of input data transformation. The study was performed on a small, carefully selected real-world data set. Here we conduct some experiments to examine these phenomena more extensively.