1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
|
% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/find.cut.R, R/find.m.R, R/find.m2.R
\encoding{UTF-8}
\name{find.cut}
\alias{find.cut}
\alias{find.m}
\alias{find.m2}
\title{Computing the threshold}
\usage{
find.cut(M, clu, alt.blocks = "reg", cuts = "all", ...)
find.m(
M,
clu,
alt.blocks = "reg",
diag = !is.list(clu),
cormet = "none",
half = TRUE,
FUN = "max"
)
find.m2(M, clu, alt.blocks = "reg", neval = 100, half = TRUE, ms = NULL, ...)
}
\arguments{
\item{M}{A matrix representing the (usually valued) network. For now, only one-relational networks are supported.
The network can have one or more modes (different kinds of units with no ties among themselves.
If the network is not two-mode, the matrix must be square.}
\item{clu}{A partition. Each unique value represents one cluster.
If the network is one-mode, then this should be a vector, else a list of vectors, one for each mode.}
\item{alt.blocks}{Only one of allowed blocktypes, as alternative to the null block:\cr
"com" - complete block\cr
"rdo", "cdo" - row and column-dominant blocks (binary, valued, and implicit approach only)\cr
"reg" - (f-)regular block\cr
"rre", "cre" - row and column-(f-)regular blocks\cr
"rfn", "cfn" - row and column-dominant blocks (binary, valued, and implicit approach only)\cr
"den" - density block (binary approach only)\cr
"avg" - average block (valued approach only).}
\item{cuts}{The cuts, which should be evaluated. If \code{cuts="all"} (default), all unique values are evaluated.}
\item{\dots}{Other parameters to \code{critFunC}.}
\item{diag}{(default = \code{TRUE}) Should the special status of diagonal be acknowledged.}
\item{cormet}{Which method should be used to correct for different maximum error contributions\cr
"none" - no correction\cr
"censor" - censor values larger than \code{M}\cr
"correct" - so that the maximum possible error contribution of the cell is the same regardless of a condition (either that something must be 0 or at least \code{M}).}
\item{half}{Should the returned value of m be one half of the value where the inconsistencies are the same.}
\item{FUN}{(default = "max") Function f used in row-f-regular, column-f-regular, and f-regular blocks.}
\item{neval}{A number of different \code{m} values to be evaluated.}
\item{ms}{The values of m where the function should be evaluated.}
}
\value{
A matrix of maximal \code{m/cut} values.
}
\description{
The functions compute the maximum value of \code{m/cut} where a certain block is still classified as \code{alt.blocks} and not "null".
The difference between \code{find.m} and \code{find.m2} it that \code{find.m} uses an optimization approach and is faster and more precise
than \code{find.m2}. However, \code{find.m} only supports regular ("reg") and complete ("com") as \code{alt.blocks}, while \code{find.m2} supports all block types.
Also, \code{find.m} does not always work, especially if \code{cormet} is not "none".
}
\references{
Doreian, P., Batagelj, V. & Ferligoj, A. \enc{Anuška}{Anuska} (2005). Generalized blockmodeling, (Structural analysis in the social sciences, 25). Cambridge [etc.]: Cambridge University Press.
\enc{Žiberna, A.}{Ziberna, A.} (2007). Generalized Blockmodeling of Valued Networks. Social Networks, 29(1), 105-126. doi: 10.1016/j.socnet.2006.04.002
\enc{Žiberna, A.}{Ziberna, A.} (2008). Direct and indirect approaches to blockmodeling of valued networks in terms of regular equivalence. Journal of Mathematical Sociology, 32(1), 57-84. doi: 10.1080/00222500701790207
\enc{Žiberna, A.}{Ziberna, A.} (2014). Blockmodeling of multilevel networks. Social Networks, 39(1), 46-61. doi: 10.1016/j.socnet.2014.04.002
}
\seealso{
\code{\link{critFunC}} and maybe also \code{\link{optParC}}, \code{\link{plotMat}}
}
\author{
\enc{Aleš Žiberna}{Ales Ziberna}
}
\keyword{cluster}
|
