Electronic Proceedings of the Fifteenth Annual International Conference on Technology in Collegiate Mathematics

Orlando, Florida, October 31-November 3, 2002

Paper C022

Visual EDFSoftware to Check the Normality Assumption

Maria E. Calzada


Loyola University New Orleans
New Orleans, LA 70118
USA
Phone: (504) 865-2491

Stephen M. Scariano


Loyola University New Orleans
New Orleans, LA 70118
USA
Phone: (504) 865-2491

Click to access this paper: paper.pdf
Additional file(s) associated with this paper:
  • files (directory) Visual Basic executable - see readme.txt

ABSTRACT

A host of materials in an introductory level statistics course relies on the 'normality assumption.' However, assessing normality is a very subtle and difficult task, even for expert data analysts. To aid our student's understanding we have written a program that implements a visual version of the Lilliefors test for normality and the powerful Anderson-Darling test for normality. In this paper we introduce these tests and show their usefulness through examples. The software, which is freely available to interested parties at http://www.loyno.edu/~calzada, should be used as a complement to other statistical techniques, like histograms and probability plots.

Keyword(s): statistics