Published in Scientific Bulletin. Series F. Biotechnologies, Vol. XIX
Written by Mioara VARGA
In this paper, we discuss about an application of Analysis of Variances from biology. We are interested to determine the effect of adding the NaCN (sodium cyanide) on the uptake in vitro of a particular amino acid by intestinal preparations from certain species of fish. First, we introduce some theoretical notions about this statistical method; we present the most important calculation formulas and the way they are used for comparing the treatment means in case of an experiment with k treatments, b blocks and n replicates per treatment per block. Afterwards, we consider a twotreatment experiment (with and without NaCN) and the results obtained for three replicates from each of the 4 species of fish are expressed asμ mol g−1dry weight per 20 min period. After we calculate the sums of observational data per sub-class, per treatment and grand totals, we determine the elements from the table of analysis of variances (sums of squares, degrees of freedom, the error mean square) and we use the Fisher test for establishing the conclusions. Then we find that the difference between treatment means is 0,49, thus with 95 % confidence probability, we may state that the addition of the NaCN to the medium reduces uptake by 0,68μ mol g−1dry weight per 20 min period.
[Read full article] [Citation]
degrees of freedom
