We consider the use of top-points for object retrieval. These points are based on scale-space and catastrophe theory, and are invariant under gray value scaling and offset as well as scale-Euclidean transformations. The differential properties and noise characteristics of these points are mathematically well understood. It is possible to retrieve the exact location of a top-point from any coars...

We consider the use of so-called top-points for object retrieval. These points are based on scale-space and catastrophe theory, and are invariant under gray value scaling and offset as well as scale-Euclidean transformations. The differential properties and noise characteristics of these points are mathematically well understood. It is possible to retrieve the exact location of a top-point from...

Personal bests act as reference points. Examining 133 million chess games, we find that players exert effort to set new personal best ratings and quit once they have done so. Although specific and difficult goals have been shown to inspire greater motivation than vague pronouncements to "do your best," doing one's best can be a specific and difficult goal-and, as we show, motivates in a manner ...

493 In a recent paper Hart and Moore (2008) develop a theory which provides a basis for long-term contracts in the absence of noncontractible investments. The theory is also capable of rationalizing the employment contract, which fixes wages in advance and leaves discretion to the employer. However, the theory rests on strong behavioral assumptions that lack direct empirical support and deviate...

A point-free formulation of the König Lemma for trees with uniformly at most one infinite path allows for a constructive proof without unique choice. 2000 Mathematics Subject Classification: 03E25, 03F65 (primary); 05C05, 05C38, 05C63 (secondary)