Survey on Sample Sizes of Postgraduate Theses in Agricultural Education and Extension in Universities of Nigeria

Michael Ejime Ikehi, Francis M. Onu, Florence O. Ifeanyieze, Patrick S. Paradang, Mmachukwu G. Nwakpadolu, Lilian U. Ekenta, Clara U. Nwankwo


The study focused on the representativeness of the sample sizes generated for populations under study in survey studies in Agricultural Education and Agricultural Extension. The study was carried out in Nigeria. A total of 4561 completed survey theses submitted to the Departments of Agricultural Education and Agricultural Extension in federal universities in Nigeria for the award of various postgraduate degrees between 2008 and 2018 were studied. The objectives of the study were to report the effect of sample size on the confidence level and margin of error of the generated data and to determine the frequently cited formula for generating sample sizes and their implications. The most frequently cited method for generating sample sizes was reported. Findings further revealed the problems associated with using nonstatistical methods to generate sample sizes. The study recommended the use of mathematically proven formula in determining sample sizes in survey studies to generate statistically dependable, reliable and generalizable data.


Post graduate thesis; Confidence level; Margin of error; Population; Sampling error, Survey; Nigeria

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