A Didactic Experience of Statistical Analysis for the Determination of Glycine in a Nonaqueous Medium Using ANOVA and a Computer Program

Abstract

This article describes the statistical comparison of two back-titration methods for the determination of glycine in a glacial HAc medium. The titration is carried out using perchloric acid. The glycine quantities obtained were determined by several groups of students on the same day (three groups a day, on average; a total of 32 groups during the academic year) and were compared by two-way ANOVA with the Statgraphics Plus 3.0 computer program. The laboratory exercise discussed in this article is recommended for fourth-year undergraduates.

Iron Quantification in Dietary Supplements using Four Colorimetric Assays

“…It is utilized to observe the interaction between the two qualitative variables (factors). Two-way ANOVA tests the effect of two factors at the same time …”

“…Two-way ANOVA tests the effect of two factors at the same time. 94 Analysis of the data provided in Spreadsheet 1 using posthoc tests (Table 2) showed that there is a difference between some of the assay for dietary supplements, suggesting an interaction between the dietary supplement samples and the assay. We verify that it was any interaction between the samples and the variables using two-way ANOVA.…”

The Importance and Efficacy of Using Statistics in the High School Chemistry Laboratory

“…In regards to implementing sta-tistics, there is a need for sufficient experimental data and a convenient method to gather the data. While making repeated measurements for statistical analysis was not feasible, the required number of measurements was obtained by pooling the data among students and classes (e.g., 7,10,11,13).…”

“…While there are many statistical tests, students in my classes used the two-sample t-test (1,2,4,7,12,15), onesample t-test (1,4,9,15), or one-factor analysis of variance (ANOVA; 3,4,10,15) to analyze their experimental data. The description of the use of other statistical tests are beyond the scope of this paper.…”

“…Despite the value of statistics, a search of articles in the Journal of Chemical Education using the keyword "statistics" produced no articles on the use of statistics in a high school chemistry course (6). While there were many papers using statistics in various college chemistry laboratory courses (e.g., [7][8][9][10][11], these papers described few statistical tests and experiments; as such, these articles provide a limited view of the use of statistics in a chemistry course.…”