profile.dmc: Profile a DMC Object

In TasCL/ggdmc: Dynamic Model of Choice with Parallel Computation, and C++ Capabilities

Description

Profile a DMC model based a model data instance (ie fitted). For the parameter p.name, e.g., the boundary separation a in a DDM, extract it our from a p.vector and draws the profile likelihood for data and returns the maximum (on a grid of resolution n.point)

Usage

## S3 method for class 'dmc'
profile(fitted, p.name, min.p, max.p, p.vector, n.point = 100,
  digits = 2, ...)

Arguments

fitted	a DMC model data instance
p.name	indicate which paramter in theta to plot. For example, in a LBA model with a pVec <- c(A="1",B="1",mean_v="M",sd_v="1",t0="1", st0="1"), one can assign p.name <- "A" to ask profile.dmc to profile A parameter
min.p	minimal number of points to plot
max.p	maximal number of points to plot
p.vector	a parameter vector. Use Lognromal LBA model as an example, pVec <- c(A=.25, B=.35, meanlog_v.true=1, meanlog_v.false=.25, sdlog_v.true=.5,t0=.2)
n.point	grid resolution
digits	print out how many digits
...	other graphical parameters (see par)

Details

Set a range for the x axis, which is the profiled parameter. Initiate a log-likelihodd vector with 0 everywhere and length n.point. keep the other parmaters value fixed and change only the target parameter value to ps[i], and then calculate its sum of log-likelihood. Finally, store it in the i position of ll vector. This function currently works for DDM density only.

Examples

m1 <- model.dmc(
p.map=list(a="1",v="1",z="1",d="1",sz="1",sv="1", t0="1",st0="1"),
constants=c(st0=0,d=0),
match.map=list(M=list(s1="r1",s2="r2")),
factors=list(S=c("s1","s2")),
responses=c("r1","r2"),
type="rd")

p.prior <- prior.p.dmc(
  dists = rep("tnorm", 6),
  p1=c(a=2,   v=2.5, z=0.5, sz=0.3, sv=1,  t0=0.3),
  p2=c(a=0.5, v=.5,  z=0.1, sz=0.1, sv=.3, t0=0.05),
  lower=c(0,-5, 0, 0, 0, 0),
  upper=c(5, 7, 2, 2, 2, 2))

pVec <- c(a=1,v=1, z=0.5, sz=0.25, sv=0.2,t0=.15)
dat1 <- simulate(m1, nsim=1e2, p.vector=pVec)
mdi1 <- data.model.dmc(dat1, m1)

## ---------------------------
par(mfrow=c(2,3));
profile(mdi1, "a",  .1,   2, pVec)
profile(mdi1, "v",  .1,   2, pVec)
profile(mdi1, "z",  .2,  .8, pVec)
profile(mdi1, "sz", .1,  .9, pVec)
profile(mdi1, "sv", .1,   2, pVec)
profile(mdi1, "t0", .01, .5, pVec)
par(mfrow=c(1,1));

TasCL/ggdmc documentation built on May 9, 2019, 4:19 p.m.