getRecordForUser: Gets or makes the student record for a given student.

In ralmond/EABN: Evidence Accumulation Bayes Net Engine

Gets or makes the student record for a given student.

Description

The BNEngine contains a StudentRecordSet, which is a collection of StudentRecord objects. The function getRecordForUser fetches one from the collection (if it exists) or creates a new one.

Usage

getRecordForUser(eng, uid, srser = NULL)

Arguments

eng	The BNEngine in question.
uid	A character scalar giving the unique identifier for the student.
srser	A serialized version of the student record. Used to extract the student record in database-free mode. This should either be a list which is the output of fromJSON or NULL.

Details

The student record set can either be attached to a database (the dburi field passed to StudentRecordSet is non-empty, or not. In the database mode, recrods are saved in the database, so that they can be retrieved across sessions. In the database-free mode, the serialized student record (if it exists) should be passed into the getRecordForUser function.

If no student record is available for the uid, then a new one is created by cloning the default student record (see setupDefaultSR).

This function mostly just calls getSR on the StudentRecordSet; however, if a new record is generated, then announceStats is called to advertise the baseline statistics for the new user.

Value

The StudentRecord object is returned.

Warning

Calling this multiple times will not return the same student record. In particular, the student model associated with the old version of the record could be replaced with a new version, rendering the student model in the old records inactive. Be careful when dealing with old records.

Author(s)

Russell Almond

References

Almond, Mislevy, Steinberg, Yan and Williamson (2015). Bayesian Networks in Educational Assessment. Springer. Especially Chapter 13.

See Also

BNEngine, StudentRecordSet, StudentRecord

handleEvidence, setupDefaultSR, fetchSM, getSR

Examples

library(PNetica)

##Start with manifest
sess <- RNetica::NeticaSession()
RNetica::startSession(sess)

## BNWarehouse is the PNetica Net Warehouse.
## This provides an example network manifest.
config.dir <- file.path(library(help="Peanut")$path, "auxdata")
netman1 <- read.csv(file.path(config.dir,"Mini-PP-Nets.csv"),
                    row.names=1, stringsAsFactors=FALSE)
net.dir <- file.path(library(help="PNetica")$path, "testnets")
stattab <- read.csv(file.path(config.dir, "Mini-PP-Statistics.csv"),
                    as.is=TRUE)
Nethouse <- PNetica::BNWarehouse(manifest=netman1,session=sess,key="Name",
                       address=net.dir)


cl <- new("CaptureListener")
listeners <- list("cl"=cl)

ls <- ListenerSet(sender= "EAEngine[Test]",
                  db=MongoDB(noMongo=TRUE), listeners=listeners)

eng <- newBNEngineNDB(app="Test",warehouse=Nethouse,
                     listenerSet=ls,manifest=netman,
                     profModel="miniPP_CM",
                     histNodes="Physics",
                     statmat=stattab,
                     activeTest="EAActive.txt")

## Standard initialization methods.
loadManifest(eng,netman1)
eng$setHistNodes("Physics")
configStats(eng,stattab)
setupDefaultSR(eng)

sr0a <- getRecordForUser(eng,"Student1")
sr0 <- getRecordForUser(eng,"Student1")
## This is announcing twice, so not quite working with NDB engine.

stopifnot(is.active(sm(sr0)),!is.active(sm(sr0a)))
stopifnot(all.equal(stats(sr0),stats(sr0a)))
eap0<- stat(sr0,"Physics_EAP")


e1 <- EvidenceSet(uid="Student1",app="Test",context="PPcompEM",
                  obs=list("CompensatoryObs"="Right"))

e1 <- logEvidence(eng,sr0,e1)
sr1 <- accumulateEvidence(eng,sr0,e1)
stopifnot(m_id(sr1)!=m_id(sr0),sr1@prev_id==m_id(sr0))
stopifnot(seqno(sr1)==1L, seqno(e1)==1L)

eap1 <- stat(sr1,"Physics_EAP")
stopifnot(abs(eap1-eap0) > .001)
stopifnot(nrow(history(sr1,"Physcis"))==2L)

sr1.ser <- as.json(sr1)
WarehouseFree(Nethouse,PnetName(sm(sr1))) # Delete student model to
                                           # force restore.
sr1a <- getRecordForUser(eng,"Student1",jsonlite::fromJSON(sr1.ser))
#PnetCompile(sm(sr1a))
eap1a <- stat(sr1a,"Physics_EAP")
stopifnot(abs(eap1-eap1a) < .001)
stopifnot(nrow(history(sr1a,"Physcis"))==2L)


##  <<Here>>  Need test with Mongo engine

ralmond/EABN documentation built on Aug. 30, 2023, 12:52 p.m.