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The Federal University of Technology (FUTA) has emerged best institution at the second edition of Nigerian Statistical Association Competition for Undergraduate Students held in Kwali, Federal Capital Territory (FCT).Out of 42 final year students from 21 tertiary institutions in attendance, Merua Ozomela from Micheal Okpara University of Agriculture, Umudike, Abia state, emerged the overall best student while for institution performance, Micheal Okpara University of Agriculture, Umudike, emerged second best institution and Usman Dan Fodiyo University, Sokoto, emerged third best institution.

# Generalizing Sample Size of Normally Distributed Samples using Generalized Exponential Power Distribution

AUTHOR(S):

### T. Soyinka

JOURNAL: Journal of the Nigerian Statistical Association Vol. 28, 2016
YEAR: 2016

## ABSTRACT

There are various sample size estimation formulas that are published in literature but has no adequate mathematical and statistical background. Many of such formula often assumed normal distribution that becomes unreliable most especially when observations are few. This study thus, established sample size estimation formula from generalized exponential power distribution (GEPD) which has normal, Laplace and uniform distribution has its members. We employed an approximation to the incomplete gamma cumulative distribution function of the GEPD via series expansion to obtain the pivotal quantity from which the sample size of GEPD was derived. Application to sample size calculation from Likert scaled questionnaire was demonstrated.

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