Evaluating university courses: intuitionistic fuzzy sets with spline functions modelling digital
format: Article | STATISTICA & APPLICAZIONI - 2017 - 1
Spline functions are a very flexible and powerful tool, which has been adopted in several applied fields, such as the evaluation of Public Services. In this paper, we use splines to model membership and non-membership functions in the context of Intuitionistic Fuzzy Sets...
Bipolar distributions in fuzzy sets theory digital
format: Article | STATISTICA & APPLICAZIONI - 2015 - 2
In this paper we consider the problem of measuring latent variables with ordinal scales and we put forward an original approach to this issue, which combines the use of Intuitionistic Fuzzy Sets with the calculation of bipolar means and bipolar distributions. Intuitionistic Fuzzy theory allows a researcher to model the degree of membership and non-membership to a certain fuzzy set, as well as the residual uncertainty...
The ordinal inter-rater agreement in the evaluation of university courses digital
format: Article | STATISTICA & APPLICAZIONI - 2014 - 1
In this paper we consider the problem of the evaluation of undergraduate and graduate courses, in the context of Italian universities...
On the use of inferential confidence intervals
format: Article | STATISTICA & APPLICAZIONI - 2009 - 1
Inferential confidence intervals (CI) represent a widely used technique for testing the equality of the means of two Normal distributions by comparing two particular CI’s relative to the each mean. They allow simple graphic interpretations and result as being more informative than the traditional testing technique through the confidence levels. Yet they are unable to convey the information relative to the compatibility of the null hypothesis with the observed data usually provided by the p-value. The present paper identifies a new measure of such compatibility in the context of inferential CI’s and extends the technique to the non Normal case. Moreover, in case the null hypothesis is accepted, the problem of estimating the common mean is dealt with by means of the bounds of specific inferential CI’s. The proposed procedures are then applied to real data relative to foreign populations originating outside the European Union and sampled from the Italian territory.
Campionamento per popolazioni rare ed elusive: la matrice dei profili digital
format: Article | STATISTICA & APPLICAZIONI - 2003 - 1
We have compared four methods (center sampling, multiple frame, network and adaptive sampling) usually proposed for samples drawn from rare and/or elusive populations, for which we haven’t a frame or, if we have, is incomplete.