What's New in June, 2010?

R

• FAQ: How can I identify the first and last observations within a group in R?
• Textbook Example: Multilevel Analysis Techniques and Applications by Joop Hox, Chapter 4

SAS

• Code Fragment: Many paired t-tests
• FAQ: How can I reshape pairs data long to wide?

Stata

• FAQ: How can I use margins to understand a categorical by categorical by continuous 3-way interaction? (Stata 11)