title: Abstract: Estimation of the 4-Parameter Model with Marginal Maximum Likelihood.
authors.affiliation: a Department of Psychology , University of Minnesota.
authors.forename: Leah M
authors.initials: LM
authors.lastname: Feuerstahler
authors.affiliation: a Department of Psychology , University of Minnesota.
authors.forename: Niels G
authors.initials: NG
authors.lastname: Waller