Sessions to criteria at each sucrose/ethanol concentration were analysed using a Mann-Whitney U test. A two-way, repeated measures ANOVA, with the between subject factor genotype and within subject factor ethanol/sucrose concentration was used to evaluate potential genotype and reinforcer effects for the number of lever presses and number of reinforcers obtained. The Greenhouse-Geisser correction was applied to correct for a violation in the assumption of sphericity.
