The lift is a commonly used index in a POS data analysis.
The item lift of Item k to Item j is defined as follow:
\( l_{jk} = \frac{p_{k\mid j}}{p_k} \)
This function is applicable only to binary response data.
Usage
ItemLift(U, na = NULL, Z = NULL, w = NULL)
# S3 method for default
ItemLift(U, na = NULL, Z = NULL, w = NULL)
# S3 method for binary
ItemLift(U, na = NULL, Z = NULL, w = NULL)
Value
A matrix of item lift values with exametrika class.
Each element (j,k) represents the lift value of item k given item j,
which indicates how much more likely item k is to be correct given that
item j was answered correctly.
Arguments
U
Either an object of class "exametrika" or raw data. When raw data is given,
it is converted to the exametrika class with the dataFormat function.
na
Values to be treated as missing values.
Z
Missing indicator matrix of type matrix or data.frame. Values of 1 indicate
observed responses, while 0 indicates missing data.
w
Item weight vector specifying the relative importance of each item.
References
Brin, S., Motwani, R., Ullman, J., & Tsur, S. (1997). Dynamic itemset counting and
implication rules for market basket data. In Proceedings of ACM SIGMOD International Conference
on Management of Data (pp. 255–264). https://dl.acm.org/doi/10.1145/253262.253325