do.sammc {Rdimtools} | R Documentation |
Semi-Supervised Adaptive Maximum Margin Criterion
Description
Semi-Supervised Adaptive Maximum Margin Criterion (SAMMC) is a semi-supervised variant of AMMC by making use of both labeled and unlabeled data.
Usage
do.sammc(
X,
label,
ndim = 2,
type = c("proportion", 0.1),
preprocess = c("center", "scale", "cscale", "decorrelate", "whiten"),
a = 1,
b = 1,
lambda = 1,
beta = 1
)
Arguments
X |
an |
label |
a length- |
ndim |
an integer-valued target dimension. |
type |
a vector of neighborhood graph construction. Following types are supported;
|
preprocess |
an additional option for preprocessing the data.
Default is "center". See also |
a |
tuning parameter for between-class weight in |
b |
tuning parameter for within-class weight in |
lambda |
balance parameter for between-class and within-class scatter matrices in |
beta |
balance parameter for within-class scatter of the labeled data and consistency of the whole data in |
Value
a named list containing
- Y
an
(n\times ndim)
matrix whose rows are embedded observations.- trfinfo
a list containing information for out-of-sample prediction.
- projection
a
(p\times ndim)
whose columns are basis for projection.
Author(s)
Kisung You
References
Lu J, Tan Y (2011). “Adaptive Maximum Margin Criterion for Image Classification.” In 2011 IEEE International Conference on Multimedia and Expo, 1–6.
See Also
Examples
## generate data of 3 types with clear difference
set.seed(100)
dt1 = aux.gensamples(n=33)-50
dt2 = aux.gensamples(n=33)
dt3 = aux.gensamples(n=33)+50
## merge the data and create a label correspondingly
X = rbind(dt1,dt2,dt3)
label = rep(1:3, each=33)
## copy a label and let 20% of elements be missing
nlabel = length(label)
nmissing = round(nlabel*0.20)
label_missing = label
label_missing[sample(1:nlabel, nmissing)]=NA
## try different balancing
out1 = do.sammc(X, label_missing, beta=0.1)
out2 = do.sammc(X, label_missing, beta=1)
out3 = do.sammc(X, label_missing, beta=10)
## visualize
opar <- par(no.readonly=TRUE)
par(mfrow=c(1,3))
plot(out1$Y, pch=19, col=label, main="SAMMC::beta=0.1")
plot(out2$Y, pch=19, col=label, main="SAMMC::beta=1")
plot(out3$Y, pch=19, col=label, main="SAMMC::beta=10")
par(opar)