I understand the the cumulative gains chart shows the percentage of found targets (y-axis) (so the sensitivity) against the number of tested observations (x-axis).
For the lift chart it seems that the y-axis shows the improvement for the percentage of found targets compared to the hypothetical random model which is a line from 0-100% in the cumulative gains chart, this is called lift. However in some explanations, the lift is still plotted against the number of tested observations,
in other explanations the lift is plotted against a "cut-off" (whatever that means),
(obviously there is something wrong with the curves itself, but this is a programming issue that I produced myself - I think the curves need to be flipped horizontally). In others the lift is plotted against the "rate of positive predictions".
I guess the "rate of positive predictions" means the same as true positive rate a.k.a. sensitivity a.k.a. recall a.k.a. hit rate. What is correct for a lift chart?