Affect and Usage Choices in Simulation Problem-Solving Environments. - Ma. Mercedes T. Rodrigo; Ryan Shaun Joazeiro de Baker; Maria C. V. Lagud; Sheryl Ann L. Lim; Alexis F. Macapanpan; Sheila A. M. S. Pascua; Jerry Q. Santillano; Leima R. S. Sevilla; Jessica O. Sugay; Sinath Tep; Norma J. B. Viehland (AIED, 2007)