Using Candy Samples To Learn about Sampling Techniques and Statistical Data Evaluation
Larissa S. Canaes, Marcel L. Brancalion, Adriana V. Rossi, and Susanne Rath
Department of Analytical Chemistry, Institute of Chemistry, State University of Campinas, 13084-971 Campinas, SP, Brasil
A classroom exercise for undergraduate and beginning graduate students that takes about one class period is proposed and discussed. It is an easy, interesting exercise that demonstrates important aspects of sampling techniques (sample amount, particle size, and the representativeness of the sample in relation to the bulk material). The exercise also explores a simple statistical approach to commonly used parameters (mean, median, standard deviation, errors, quartiles, confidence limits); the presentation of results using histogram, box-plot and whisker plot; and the related tests (normality, outliers, significance) using parametric and non-parametric statistical methods.
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