simu.6pt {MLDS}R Documentation

Perform Bootstrap Test on 6-point Likelihood for MLDS FIT

Description

Using the fitted responses (probabilities) to the difference scale, new responses are generated which permit new 6-point likelihoods to be calculated. The distribution of a large number of such likelihoods can be compared with that obtained from the observed responses to evaluate the internal consistency of the estimated scale.

Usage

simu.6pt(obj, nsim = 1)

Arguments

obj object of class ‘mlds’
nsim integer indicating number of bootstrap trials.

Value

LIST with 4 components

boot.samp vector of numeric giving the log likelihood for the 6-point test for each simulation.
lik6pt numeric indicating the log likelihood for the 6-point test on the original data
p proportion of simulations on which the simulated log likelihood was higher than that obtained from the original sample.
N numeric indicating the number of simulations. It should be the length of boot.samp.

Author(s)

Kenneth Knoblauch and Laurence T. Maloney

References

Maloney, L. T. and Yang, J. N. (2003). Maximum likelihood difference scaling. Journal of Vision, 3(8):5, 573–585, http://journalofvision.org/3/8/5/, doi:10.1167/3.8.5.

See Also

mlds, lik6pt

Examples

        data(kk1)
        x.mlds <- mlds(SwapOrder(kk1))
        #nsim should be near 10,000 for stability,
        # but this will take a little time
        simu.6pt(x.mlds, 100)

[Package MLDS version 0.1-7 Index]