Remember James Boswell, ninth Laird of Auchinleck, author of the famous maxim that the road to hell is paved with good intentions? Trying to build realistic theories differs dramatically from having correct explanatory theories tested on objective criteria, e.g., verifiable prediction....

Eric Tsang's response makes the legitimate point that prediction and explanation can be different goals. However, his arguments also suffer from several errors in logic, most often the converse error. I do not claim that unrealistic assumptions breed good theories. I only claim that breakthrough...

This research has three objectives: (i) to compile analytical results on national brand and store brand marketing obtained from mathematical models, (ii) to assess the external validity of those results and thus the applicability of the results to practice, and (iii) to identify avenues for...

Observing reality is especially valuable. However, without models, every situation at every time on every variable would be unpredictable. Assumptions allow models and theories to assert constancy. Assumptions distill and simplify reality by dismissing the conspicuous but irrelevant. Criticizing...