umx (version 1.4.0)

umxIP: umxIP

Description

Make a 2-group Independent Pathway twin model (Common-factor independent-pathway multivariate model)

Usage

umxIP(name = "IP", selDVs, dzData, mzData, suffix = NULL, nFac = 1, freeLowerA = FALSE, freeLowerC = FALSE, freeLowerE = FALSE, equateMeans = TRUE, dzAr = 0.5, dzCr = 1, correlatedA = FALSE, addStd = TRUE, addCI = TRUE, numObsDZ = NULL, numObsMZ = NULL, autoRun = getOption("umx_auto_run"))

Arguments

name

The name of the model (defaults to "IP")

selDVs

The variables to include

dzData

The DZ dataframe

mzData

The MZ dataframe

suffix

The suffix for twin 1 and twin 2, often "_T". If set, you can omit suffixes in SelDVs, i.e., just "dep" not c("dep_T1", "dep_T2")

nFac

How many common factors (default = 1)

freeLowerA

Whether to leave the lower triangle of A free (default = F)

freeLowerC

Whether to leave the lower triangle of C free (default = F)

freeLowerE

Whether to leave the lower triangle of E free (default = F)

equateMeans

Whether to equate the means across twins (defaults to T)

dzAr

The DZ genetic correlation (defaults to .5, vary to examine assortative mating)

dzCr

The DZ "C" correlation (defaults to 1: set to .25 to make an ADE model)

correlatedA

Whether factors are allowed to correlate (not implemented yet: FALSE)

addStd

Whether to add the algebras to compute a std model (defaults to TRUE)

addCI

Whether to add the interval requests for CIs (defaults to TRUE)

numObsDZ

= todo: implement ordinal Number of DZ twins: Set this if you input covariance data

numObsMZ

= todo: implement ordinal Number of MZ twins: Set this if you input covariance data

autoRun

Whether to mxRun the model (default TRUE: the estimated model will be returned)

Value

- mxModel

Details

The following figure shows the IP model diagramatically:

IP.png

References

- http://www.github.com/tbates/umx

See Also

- plot(), umxSummary() work for IP, CP, GxE, SAT, and ACE models.

Other Twin Modeling Functions: plot.MxModel, umxACESexLim, umxACEcov, umxACE, umxCF_SexLim, umxCP, umxGxE_window, umxGxE, umxPlotACEcov, umxPlotCP, umxPlotGxE, umxPlotIP, umxSummaryACEcov, umxSummaryACE, umxSummaryCP, umxSummaryGxE, umxSummaryIP, umx_make_TwinData, umx

Examples

require(umx)
data(twinData)
zygList = c("MZFF", "MZMM", "DZFF", "DZMM", "DZOS")
twinData$ZYG = factor(twinData$zyg, levels = 1:5, labels = zygList)
mzData <- subset(twinData, ZYG == "MZFF")
dzData <- subset(twinData, ZYG == "DZFF")
selDVs = c("ht", "wt") # These will be expanded into "ht1" "ht2"
m1 = umxIP(selDVs = selDVs, suffix = "", dzData = dzData, mzData = mzData)
umxSummary(m1)
plot(m1)