Why Healthy Behavior Is the Hard Choice

Why healthy behavior is the hard choice.

Why Supertagging Is Hard

Tree adjoining grammar parsers can use a supertagger as a preprocessor to help disambiguate the category1 of words and thus speed up the parsing phase dramatically. However, since the errors in supertagging propagate to this phase, it is vital to keep the error rate of the supertagger phase reasonably low. With very large tagsets coming from extracted grammars, this error rate can be of almost ...

Why Matrix Theory is Hard

Recently Sen and Seiberg gave a prescription for constructing the matrix theory in any superstring background. We use their prescription to test the finite N matrix theory conjecture on an ALE space. Based on our earlier work with Shenker, we find a sharper discrepancy between matrix theory computation and supergravity prediction. We discuss subtleties in the light-front quantization which may ...

Why Security Testing Is Hard

PUBLISHED BY THE IEEE COMPUTER SOCIETY 1540-7993/03/$17.00 © 2003 IEEE IEEE SECURITY & PRIVACY 83 application operates as specified) much easier. However, several types of bugs routinely escape testing. Many of these flaws are not specification violations in the traditional sense, meaning that the application might behave correctly according to requirements, but it might perform some additional...

Why the Cosmological Constant Problem is Hard

We consider a recent proposal to solve the cosmological constant problem within the context of brane world scenarios with infinite volume extra dimensions. In such theories bulk can be supersymmetric even if brane supersymmetry is completely broken. The bulk cosmological constant can therefore naturally be zero. Since the volume of the extra dimensions is infinite, it might appear that at large...