Maria Angeles Gil

Prof. María Ángeles Gil,
University of Oviedo, Spain

Fuzzy Rating Scales of measurement: a psychometric tool capturing imprecisión and individual differences

In introducing Fuzzy Sets, Lotfi A. Zadeh anticipated that they would play an important role in human thinking. Fuzzy rating scales were developed as a psychometric tool aiming to appropriately capture the natural imprecision involved in measuring many variables in Social Sciences. Furthermore, these scales also cope with the individual differences in such a measurement, so they look to be more informative from a statistical perspective than other usual ones (namely, the Likert type, the visual analogue and the fuzzy linguistic scales).

This talk recalls the main ideas and features behind fuzzy rating scales, as well as their applications to design items in questionnaires. Possible soundly formalized methods to analyze fuzzy rating scale-based data are to be reviewed. Some of the advantages of using these scales in contrast to traditional ones are also to be discussed and illustrated.


María Ángeles Gil is Full Professor of Statistics and O.R. at the University of Oviedo (Spain). She got her BSc and MSc in Math from the University of Valladolid and her PhD in Math from the University of Oviedo (Principality of Asturias, Spain). Her research was initially focused on the measurement and statistical developments concerning the amount of information and inequality of random variables. Fort the last decades her research interests have been mostly related to the statistical analysis of imprecise data (more concretely, set- and fuzzy set-valued ones), a topic in which she has supervised several PhD theses and R+D projects. She was co-editor-in-chief of the statistical journal TEST (2005-2008) and associate/area editor for several other international journals. She has been awarded with the Silver Medal of the Principality of Asturias in 2014 and is an IFSA fellow since 2015.