A Multi-Site Joint Replication of a Design Patterns Experiment Using Moderator Variables to Generalize across Contexts /Jonathan L. Krein, Lutz Prechelt, Member, IEEE, Natalia Juristo, Aziz Nanthaamornphong, Member, IEEE, Jeffrey C. Carver, Senior Member, IEEE, Sira Vegas, Charles D. Knutson, Member, IEEE, Kevin D. Seppi, and Dennis L. Eggett - Krein,Jonathan L.