Figure 12. The same manipulation, in the same sessions, moved performance and self-assessment more than raw knowledge scores. Every between-group contrast in both studies on one standardized axis: Hedges’
g for AI-supported minus Control with
95% confidence intervals, ordered by magnitude. Filled points exclude zero, open points include it. So that the axis is comparable, each contrast is recomputed here as a between-person
g on per-participant means, which is not always the estimator the text uses for the same quantity: in particular the unaided-performance point is the Phase-B level contrast between groups, whereas H2’s registered test is the phase
× condition interaction, which is large and significant ( Section 4 ). The knowledge points are proportion correct, the one scale the two batteries share. Study 2’s registered analysis was latent
θ from a 2PL and is reported in Section 6 . Performance while the advisor is present is the largest effect in either study. The subjective registers follow at between one-quarter and two-fifths of a standard deviation, with confidence and felt understanding close in magnitude across the two samples and perceived control in the same direction but significant only in Study 2. The raw prediction and structural-knowledge contrasts are statistically unresolved, with point estimates of
+0.12 and
+0.16 . Effort runs the other way, aided participants reporting less of it. Because every contrast is standardized within the same participants and the same sessions, the figure compares magnitudes. It does not establish knowledge equivalence. Study 1
n=200 , Study 2
n=198 ; per-contrast
n varies slightly with instrument completion. A forest plot of fifteen standardized effect sizes, Hedges' g for AI-supported minus Control, ordered from largest positive at the top to largest negative at the bottom. Firm solvency in Study 2 (about plus 0.91) and aided-phase performance in Study 1 (about plus 0.76) sit near plus one as filled points, followed by performance on rising months in Study 2 (about plus 0.51). The confidence, felt understanding and perceived-control contrasts from both studies cluster between plus 0.26 and plus 0.44, mostly filled, and the unaided-phase persistence-reference contrast from Study 1 (about plus 0.32) sits filled among them. Near zero, as open points with intervals crossing it, are the prediction and structural-knowledge contrasts (about plus 0.16 and plus 0.12) and the Phase-B performance level contrast (about zero). The two mental-effort contrasts sit as filled points between minus 0.45 and minus 0.59.