Instantiation
Objects are created via calls of the form new("mRMRe.Data", data, strata, weights, priors)
.
data
: is expected to be a data frame with samples and features respectively organized as rows and columns. The columns
have to be of type :{numeric, ordered factor, Surv} and respectively interpreted as :{continuous, discrete and survival} variables.
strata
: is expected to be a vector of type :{ordered factor} with the strata associated to the samples provided
in data
.
weights
: is expected to be a vector of type :{numeric} with the weights associated to the samples provided
in data
.
priors
: is expected to be a matrix of type :{numeric} where priors[i, j]
: denotes an forced association between
features i and j in data
. The latter takes into consideration the directionality of the relationship and must be a value
between 0 and 1.Mutual Information Matrix
The mim
method computes and returns a mutual information matrix. A correlation between continuous features is estimated
using an estimator specified in continuous_estimator
; currently, :{pearson, spearman, kendall, frequency} are supported.
The estimator for discrete features is Cramer's V and for all other combinations, concordance index.
When outX
is set to TRUE
, ties are ignored when computing the concordance index and otherwise, these are considered.
The correlations are first computed per strata and these are then combined by the inverse variance weight mean of the estimates
using a bootstrap_count
number of bootstraps if the former parameter is greater than 0, and by the relative weights of each
strata otherwise. The resulting correlation is then summated with the corresponding value in the priors matrix with the
latter being weighed for a proportion prior_weight
of a final, biased correlation.