The answers were converted to numeric values, “I like it extremely well”
being designated number 1 and “I dislike it extremely” number 9.
The average grade was obtained from the reported data.
2.11. Statistical analysis
Data analysis was performed using the program Statistica 7.0 by StatSoft, Inc. (2004), the analysis of variance (ANOVA) and the Tukey test (P 0.05).
The experimental data are presented as the mean standard deviation (SD).