Thursday, 03 June, 2010 (20100603)

This week we are continuing with your dissertation data.


Just the R script  this week.


Prep work: load data and library

Converting from wide to long format
    Using reshape() and it's argument
    What if I did it wrong?
    Cleaning up long data

Graphing longitudinal data
    The group argument in ggplot2
    Mix and match layers
    Changing plot objects with %+%

Dealing with large datasets
    Taking a subset()
    Stratified random sample()s
    Handling long format data

Learning Objectives

Learn how to convert datasets from person-level to person-period format
Beginning exposure to taking a subset of a dataset
Comfort mixing and matching layer objects in ggplot2