---
title: "Psych Script"
output: html_notebook
---
## Installing the package
```{r eval=FALSE}
install.packages(c("psych","GPArotation","mnormt"))
```
```{r eval=FALSE}
library(psych)
```
## Descriptive Statistics
Marginal Description
```{r describe}
data(sat.act)
describe(sat.act)
```
Broken down by demographic groups
```{r describeby}
describeBy(sat.act,sat.act$gender,skew=FALSE,range=FALSE)
```
## Detecting Outliers
```{r outliers}
d2 <- outlier(sat.act)
tail(sort(d2))
sat.d2 <- data.frame(sat.act,d2)
```
## Scatterplot matrixes
```{r scatmat}
pairs.panels(sat.d2,bg=c("yellow","blue")[(d2 > 25)+1],pch=21)
```
## Violin (density) plot
```{r violin}
violin(sat.act[,4:6])
violinBy(sat.act,var=5:6,grp="gender",grp.name=c("M","F"))
```
## Coefficient Alpha
```{r attitude data}
attitude
```
```{r alpha}
alpha(attitude)
```
The `keys` argument can be used to reverse code some items.
```{r alpha}
alpha(attitude,keys=c("complaints","critical"))
```
## Coefficient Omega
Simulate some data:
```{r sim.hier}
r9 <- sim.hierarchical(n=500,raw=TRUE)$observed
as_tibble(round(r9,2))
```
Calculate alpha:
```{r sim.alpha}
alpha(r9)
```
Calculate Omega:
```{r sim.omega}
om.9 <- omega(r9)
om.9
```
```{r omega attributes}
omega(attitude)
```