Fits a Mallows-Bradley-Terry (MBT) model by maximum likelihood.
Usage
mbt(data, bootstrap = FALSE, nsim = 1000, ...)
Arguments
data
a data frame, the first t columns containing the ranks, the
(t + 1)th column containing the frequencies
bootstrap
logical. Return a parametric bootstrap p-value?
nsim
number of bootstrap replicates
...
further aguments passed to simulate
Value
coefficients
a vector of parameter estimates (scale values)
constrained to sum to unity
goodness.of.fit
the goodness of fit statistic including the
likelihood ratio fitted vs. saturated model (-2logL), the degrees of
freedom, the p-value of the corresponding chi-square distribution, and
if bootstrap is TRUE the bootstrap p-value
perm.idx
the names of the non-zero frequency ranks
y
the vector of rank frequencies including zeros
mbt.glm
the output from a call to glm
Details
mbt provides a front end for glm. See Critchlow and Fligner
(1991) and Mallows (1957) for details.
References
Critchlow, D.E., & Fligner, M.A. (1991).
Paired comparison, triple comparison, and ranking experiments as generalized
linear models, and their implementation in GLIM.
Psychometrika, 56, 517--533.
10.1007/bf02294488
# NOT RUN {data(tartness) # tartness rankings of salad dressings (Vargo, 1989)mbt(tartness, bootstrap=TRUE, nsim=500) # fit Mallows-Bradley-Terry model# }