MM: The Mallows model for aggregating multiple ranking lists

In ExtMallows: An Extended Mallows Model and Its Hierarchical Version for Ranked Data Aggregation

Description

It uses the Mallows model to aggregate multiple full/partial ranking lists.

Usage

MM(rankings, initial.method, it.max)

Arguments

rankings	A n by m matrix, with each column representing a ranking list, which ranks the items from the most preferred to the least preferred. For missing items, use 0 to denote them.
initial.method	the method for initializing the value of pi0, with four options: mean, median, geometric and random (the mean of three randomly sampled ranking lists). By default, initial.method="mean".
it.max	the maximum number of iterations. By default, it.max=20.

Value

op.phi	optimal value of phi
op.pi0	optimal value of pi0, ranking the items from the most preferred to the least preferred
max.logL	maximum value of log-likelihood

Author(s)

Han Li, Minxuan Xu, Jun S. Liu and Xiaodan Fan

References

Mallows, C. L. (1957). Non-null ranking models, Biometrika 44(1/2): 114-130.

Examples

data(simu1)
res=MM(rankings = simu1, initial.method = "mean", it.max = 20)
res$op.phi
res$op.pi0

ExtMallows documentation built on May 1, 2019, 8:45 p.m.