THE SKEW-NORMAL DISTRIBUTION IN SPC

• Type: Article in International Scientific Journal
• Date: 2013

Authors

Fernanda Figueiredo (Author) FEP; gomes, mi (Author) Other

Journal

Title: Revstat Statistical Journal

Vol. 11 No. 1

Pages: 83-104

ISSN: 1645-6726

Publisher: Instituto Nacional De Estatistica

Indexing

ISI Web of Knowledge - 36 Citations

ISI Web of Science

Scopus - 45 Citations

Scientific classification

FOS: Natural sciences

Other information

Authenticus ID: P-006-DE1

Abstract (EN): Modeling real data sets, even when we have some potential (as) symmetric models for the underlying data distribution, is always a very difficult task due to some uncontrollable perturbation factors. The analysis of different data sets from diverse areas of application, and in particular from statistical process control (SPC), leads us to notice that they usually exhibit moderate to strong asymmetry as well as light to heavy tails, which leads us to conclude that in most of the cases, fitting a normal distribution to the data is not the best option, despite of the simplicity and popularity of the Gaussian distribution. In this paper we consider a class of skew-normal models that include the normal distribution as a particular member. Some properties of the distributions belonging to this class are enhanced in order to motivate their use in applications. To monitor industrial processes some control charts for skew-normal and bivariate normal processes are developed, and their performance analyzed. An application with a real data set from a cork stopper's process production is presented.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 22