gtm_resp6 {gtm} | R Documentation |
Log-likelihood and component responsibilities under a Gaussian mixture
Description
The responsibility R(k,n) is the probability of a particular component in the
Gaussian mixture, k, having generated a particular data point, n. It is
calculated from the distances between the data point n and the centres of
the mixture components, 1..K, and the inverse variance, beta, common to
all components.
Usage
gtm_resp6(DIST, minDist, maxDist, beta, D, mode)
gtm_resp3(DIST, beta, D)
Arguments
DIST |
a K-by-N matrix in which element (k,n) is the squared distance
between the centre of component k and the data point n. |
minDist, maxDist |
vectors containing the minimum and maximum of
each column in DIST, respectively; 1-by-N; required iff m > 0 |
beta |
a scalar value of the inverse variance common to all components
of the mixture |
D |
dimensionality of space where the data and the Gaussian mixture
lives; necessary to calculate the correct log-likelihood |
mode |
optional argument used to control the mode of calculation; it can
be set to 0, 1 or 2 corresponding to increasingly elaborate measure taken
to reduce the amount of numerical errors; mode = 0 will be fast but less
accurate, mode = 2 will be slow but more accurate; the default mode is 0 |
Value
A list containing
llh
|
the log-likelihood of data under the Gaussian mixture |
R
|
an K-by-N responsibility matrix; R(k,n) is the responsibility
takened by mixture component k for data point n. |
See Also
gtm_dist
Examples
lv = gtm_demo()
gtm_resp3(gtm_dist(lv$T, lv$Y), lv$beta, 2)
[Package
gtm version 1.0
Index]