In data mining and association rule learning, lift is a measure of the performance of a targeting model (association rule) at predicting or classifying cases as having an enhanced response (with respect to the population as a whole), measured against a random choice targeting model. A targeting model is doing a good job if the response within the target is much better than the average for the population as a whole. Lift is simply the ratio of these values: target response divided by average response. For example, suppose a population has an average response rate of 5%, but a certain model (or rule) has identified a segment with a response rate of 20%. Then that segment would have a lift of 4.0 (20%/5%). Typically, the modeller seeks to divide the population into quantiles, and rank the quantiles by lift. Organizations can then consider each quantile, and by weighing the predicted response rate (and associated financial benefit) against the cost, they can decide whether to market to that quantile or not. Lift is analogous to information retrieval’s average precision metric, if one treats the precision (fraction of the positives that are true positives) as the target response probability. The lift curve can also be considered a variation on the receiver operating characteristic (ROC) curve, and is also known in econometrics as the Lorenz or power curve. The difference between the lifts observed on two different subgroups is called the uplift. The subtraction of two lift curves forms the uplift curve, which is a metric used in uplift modelling. It is important to note that in general marketing practice the term Lift is also defined as the difference in response rate between the treatment and control groups, indicating the causal impact of a marketing program (versus not having it as in the control group). As a result, ‘no lift’ often means there is no statistically significant effect of the program. On top of this, uplift modelling is a predictive modeling technique to improve (up) lift over control. … Lift

# If you did not already know: “Lift”

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