## 3 Inferential Statistics Results  
Table 1 shows the descriptive statistics of the results of the experiment, mean and standard deviation, corresponding to the two participants in all the three previously mentioned phases. Participant 1 (P1) score is lower in the base line (BL), for alcohol and caffeine in both ES and SFS than Participant 2 (P2). Moreover, the statistical dispersion measure in all conditions and scales is higher in P1 than in P2. Two-way repeated measures ANOVA were performed to determine whether there are significant differences in mean scores in ES between the three conditions (BL, alcohol and caffeine) for each participant. See Table 2. We have used these parametric statistical tests for the score on the ES because the score on that scale is the sum of the scores of the 4 items considered in the Likert scale for measuring EUPHORIA (cheerful, elated, exhilarated, and lively), assuming that it is an approximately continuous variable. Although Likert scales are technically ordinal because they consist of a series of ordered categories, several authors have found consistent support for using them as approximately continuous. Then, ordinal variables with five or more categories can often be used as continuous without any harm to the analysis performed on them. This fact may result in several categories much higher than the ordinal Likert scales they are calculated from. Therefore, the fact of taking the sum \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & & \multicolumn{2}{c}{**EUPHORIA**} & \multicolumn{2}{c}{**FACES**} \\ \cline{3-6}  & & **MEAN** & **SD** & **MEAN** & **SD** \\ \hline \multirow{3}{*}{P1} & BL & 3.84 & 1.068 & 3.89 & 0.315 \\  & ALCOHOL & 13.63 & 6.457 & 5.32 & 1.827 \\  & COFFE & 10.16 & 5.069 & 4.58 & 1.539 \\ \hline \multirow{3}{*}{P2} & BL & 7.63 & 1.300 & 4.58 & 1.017 \\  & ALCOHOL & 9.47 & 1.926 & 4.89 & 1.329 \\ \cline{1-1}  & COFFE & 11.53 & 1.645 & 5.53 & 0.612 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Descriptive statistics for both participants in experimental design. or mean of two or more ordinal variables to create an approximately continuous variable is something that many researchers encounter when using surveys [27; 28; 29; 30]. For the SFS analyses, as it is an ordinal single-item scale, we used the Friedman test for repeated measures and the Wilcoxon test of related samples to compare the three conditions (BL, alcohol and caffeine). The results are shown in the text (last paragraph of Section 3). The total number of registers was 19 over the course of 3 h. A factor (experimental condition) was considered with three levels, corresponding to the three phases of the experiment: A = baseline; B = alcohol; C = caffeine, for the analysis of variance of these repeated measures. The 19 registers from the two scales in each phase of the experiment were considered as the dependent variable. Thus, the 19 registers from Phase A were compared with those of Phase B and Phase C, with 19 registers each one as well. There exist significant effects of both alcohol and caffeine in ES for both participants. For example, for P1, there exist a significant effect of both drugs in ES (F(2, 36) = 27.771, \(p<0.001\), \(\eta^{2}=0.607\), \(\beta=1.000\)). In general, a medium effect size has been obtained for Cohen's value, but the power is maximum (1) in both participants. The numbers in parentheses are the degrees of freedom. In the case of F, the first number (2) corresponds to the degrees of freedom of the model and the second number (36) to the degrees of freedom of the residuals. Pairwise multiple comparisons were performed with the Bonferroni adjust for mean differences and \(t\)-test between all conditions and for both participants. See Table 3.  
In general, the effects of both drugs are higher for the ES scores than for the BL ones, but the effect of alcohol is higher in P1 than in P2 on ES, and the contrary occurs for the caffeine effect.