Repeated Measures for HAPPI + PERMA17

# Loading the dataset that has been reset into a long version
load("/Users/levibrackman/data.test.RData")
# Creating a new variable that is the mean of all positive purpose HAPPI
# questions
data.test$HAPPIPRMA17 <- apply(data.test[, c("HAPPI1", "HAPPI2", "HAPPI3", "PERMA17")], 
    1, mean, na.rm = TRUE)

For lme to work GROUP and ID need to be seen as factors

data.test$GROUP <- as.factor(data.test$GROUP)
data.test$ID <- as.factor(data.test$ID)
# Load the psych package
library(psych)

Describe the HAPPIPRMA17 variable by the GROUP variable

describeBy(data.test$HAPPIPRMA17, group = data.test$GROUP)
## group: 0
##   vars  n mean   sd median trimmed  mad  min  max range  skew kurtosis
## 1    1 80 5.55 1.32   5.75    5.71 1.11 1.75 7.75     6 -1.03     0.62
##     se
## 1 0.15
## -------------------------------------------------------- 
## group: 1
##   vars  n mean   sd median trimmed  mad  min  max range  skew kurtosis
## 1    1 70  5.7 1.19      6    5.76 1.11 1.75 7.75     6 -0.66     0.47
##     se
## 1 0.14
## -------------------------------------------------------- 
## group: 2
##   vars n mean   sd median trimmed  mad  min max range  skew kurtosis se
## 1    1 5  5.3 2.23   4.75     5.3 3.71 2.25 7.5  5.25 -0.14    -1.92  1

Create a plot that visualizes HAPPIPRMA17 variable by the GROUP variable

library(ggplot2)
## 
## Attaching package: 'ggplot2'
## 
## The following object is masked from 'package:psych':
## 
##     %+%
qplot(GROUP, HAPPIPRMA17, data = data.test, geom = "boxplot")

plot of chunk unnamed-chunk-4


# Load the nlme package
library(nlme)

Two way repeated measures


with(data.test, boxplot(HAPPIPRMA17 ~ wave + GROUP))

plot of chunk unnamed-chunk-5

Graphing the Two-Way Interaction.

# Load the nlme package
library(nlme)

I am not sure if I am doing this right

baseline <- lme(HAPPIPRMA17 ~ 1, random = ~1 | ID/GROUP/wave, data = data.test, 
    method = "ML")

HAPPIPRMA17Model <- lme(HAPPIPRMA17 ~ GROUP, random = ~1 | ID/GROUP/wave, data = data.test, 
    method = "ML")
## Error: nlminb problem, convergence error code = 1
##   message = singular convergence (7)

HAPPIPRMA172Model <- lme(HAPPIPRMA17 ~ GROUP + wave, random = ~1 | ID/GROUP/wave, 
    data = data.test, method = "ML")

fullModel <- lme(HAPPIPRMA17 ~ GROUP * wave, random = ~1 | ID/GROUP/wave, data = data.test, 
    method = "ML")

We again the significance of our models by comparing them from the baseline model using the anova() function.


anova(baseline, HAPPIPRMA17Model, HAPPIPRMA172Model, fullModel)
## Error: object 'HAPPIPRMA17Model' not found
summary(fullModel)
## Warning: NaNs produced
## Linear mixed-effects model fit by maximum likelihood
##  Data: data.test 
##     AIC BIC logLik
##   468.6 499 -224.3
## 
## Random effects:
##  Formula: ~1 | ID
##         (Intercept)
## StdDev:        1.15
## 
##  Formula: ~1 | GROUP %in% ID
##         (Intercept)
## StdDev:   0.0002096
## 
##  Formula: ~1 | wave %in% GROUP %in% ID
##         (Intercept) Residual
## StdDev:   7.215e-08   0.5626
## 
## Fixed effects: HAPPIPRMA17 ~ GROUP * wave 
##              Value Std.Error DF t-value p-value
## (Intercept)  5.364    0.2645 89  20.278  0.0000
## GROUP1      -0.583    0.3838  0  -1.518     NaN
## GROUP2      -1.664    1.0849 89  -1.533  0.1287
## wave         0.100    0.1367 59   0.728  0.4693
## GROUP1:wave  0.466    0.2054 59   2.268  0.0270
## GROUP2:wave  1.034    0.5809 59   1.779  0.0803
##  Correlation: 
##             (Intr) GROUP1 GROUP2 wave   GROUP1:
## GROUP1      -0.682                             
## GROUP2      -0.244  0.166                      
## wave        -0.727  0.504  0.177               
## GROUP1:wave  0.499 -0.758 -0.122 -0.660        
## GROUP2:wave  0.171 -0.119 -0.722 -0.235  0.155 
## 
## Standardized Within-Group Residuals:
##      Min       Q1      Med       Q3      Max 
## -3.21063 -0.38866  0.03848  0.40951  2.44969 
## 
## Number of Observations: 155
## Number of Groups: 
##                      ID           GROUP %in% ID wave %in% GROUP %in% ID 
##                      91                      92                     154