#
#   Copyright 2007-2014 The OpenMx Project
#
#   Licensed under the Apache License, Version 2.0 (the "License");
#   you may not use this file except in compliance with the License.
#   You may obtain a copy of the License at
# 
#        http://www.apache.org/licenses/LICENSE-2.0
# 
#   Unless required by applicable law or agreed to in writing, software
#   distributed under the License is distributed on an "AS IS" BASIS,
#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#   See the License for the specific language governing permissions and
#   limitations under the License.


# -----------------------------------------------------------------------------
# Program: SimpleRegression_PathRaw.R  
# Author: Ryne Estabrook
# Date: 2009.08.01 
#
# ModelType: Regression
# DataType: Continuous
# Field: None
#
# Purpose: 
#      Simple Regression model to estimate effect of independent on dependent variables
#      Path style model input - Raw data input
#
# RevisionHistory:
#      Hermine Maes -- 2009.10.08 updated & reformatted
#      Ross Gore -- 2011.06.06 added Model, Data & Field metadata
# -----------------------------------------------------------------------------

require(OpenMx)
# Load Library
# -----------------------------------------------------------------------------

data(myRegDataRaw)

names(myRegDataRaw)

myRegDataRaw <- myRegDataRaw[,c("x","y")]
# Prepare Data
# -----------------------------------------------------------------------------

uniRegModel <- mxModel("Simple Regression Path Specification", 
      type="RAM",
      mxData(
      		observed=myRegDataRaw, 
      		type="raw"
      ),
      manifestVars=c("x","y"),
      mxPath(from=c("x","y"), 
            arrows=2,
            free=TRUE, 
            values = c(1,1),
            labels=c("varx","residual")
      ), 
	  # variances
      # -------------------------------------
      mxPath(from="x",
            to="y",
            arrows=1,
            free=TRUE,
            values=1,
            label="beta1"
      ), 
      # regression weight
      # -------------------------------------
      mxPath(from="one",
            to=c("x","y"),
            arrows=1,
            free=TRUE,
            values=c(1,1),
            labels=c("meanx","beta0")
      ) 
      # means
      # -------------------------------------
) # close model
# Create an MxModel object
# -----------------------------------------------------------------------------
      
uniRegFit <- mxRun(uniRegModel, suppressWarnings=TRUE)

summary(uniRegFit)
uniRegFit$output


omxCheckCloseEnough(uniRegFit$output$estimate[["beta0"]], 2.5478, 0.001)
omxCheckCloseEnough(uniRegFit$output$estimate[["beta1"]], 0.4831, 0.001)
omxCheckCloseEnough(uniRegFit$output$estimate[["residual"]], 0.6652, 0.001)
omxCheckCloseEnough(uniRegFit$output$estimate[["meanx"]], 0.0542, 0.001)
omxCheckCloseEnough(uniRegFit$output$estimate[["varx"]], 1.1053, 0.001)
# Compare OpenMx results to Mx results 
# -----------------------------------------------------------------------------