A Broomean Model of Rationality and Reasoning

John Broome has developed an account of rationality and reasoning which gives philosophical foundations for choice theory and the psychology of rational agents. We formalize his account into a model that differs from ordinary choice-theoretic models through focusing on psychology and the reasoning process. Within that model, we ask Broome’s central question of whether reasoning can make us more rational: whether it allows us to acquire transitive preferences, consistent beliefs, non-akratic intentions, and so on. We identify three structural types of rationality requirements: consistency requirements, completeness requirements, and closedness requirements. Many standard rationality requirements fall under this typology. Based on three theorems, we argue that reasoning is successful in achieving closedness requirements, but not in achieving consistency or completeness requirements. We assess how far our negative results reveal gaps in Broome's theory, or deficiencies in choice theory and behavioral economics.

Handling Extemporaneous Information in Requirements Engineering

The key of the success or failure of a software project depends on solving the right problem (Rumbaugh, 1994; Sawyer, 2005). Thus, software requirements should be correct, unambiguous, consistent, and as complete as possible (Institute of Electrical and Electronics Engineers [IEEE], 1998). Errors in requirements raise software development and maintenance costs notoriously (Katasonov & Sakkinen, 2006). The later the requirement error is detected, the higher the correction cost turns out to be. Error correction costs have been widely studied by many researchers (Bell & Thayer, 1976; Davis, 1993). Errors in requirements may be due to several reasons such as poor communication among requirements engineers, clients, and users; poor or nonexistent requirements validation; and the level of sternness of the models being used, especially to model relevant information captured from the universe of discourse (UofD). Requirements engineering is the area of software engineering responsible for proposing and developing solutions to elicit, model, and analyze requirements by means of heuristics, guidelines, models, and processes which tend to requirements’ completeness, quality, correctness, and consistency. Many proposals have been put forward by many researchers (Bubenko & Wrangler, 1993; Jacobson, Christerson, Jonsson, & Overgaard, 1992; Leite & Oliveira, 1995; Macaulay, 1993; Reubenstein & Waters, 1991).