Library
Is it possible to create formative-type factors in BayesiaLab?
Quote 0 0
Library
By default, the factor constructs generated with the PSEM workflow are reflective.However, at least in theory, nothing prevents you from having links in the other direction. There are two challenges though:[list=1:lt2stxxr][*:lt2stxxr]Defining the factor variables, either with BayesiaLab's equation editor or with an external tool.[/*:m:lt2stxxr][*:lt2stxxr]The size of the Conditional Probability Table (CPT) associated with the factor increases exponentially as a function of the number of its manifests. This effectively limits the number of manifests that can be included in such a construct (see the CPT below with 4 manifest variables only).[/*:m:lt2stxxr][/list:lt2stxxr]CPT.png CPT1.png A pure formative construct (without links between the manifests) in a BBN is a model where:[*:lt2stxxr]the manifests variables are marginally independent form each other and conditionally dependent given evidence on the latent variable,[/*:m:lt2stxxr][*:lt2stxxr]each manifest has an impact on the latent that is fully dependent on the context defined by the states of the other manifest variables.[/*:m:lt2stxxr]
Quote 0 0