We present the first necessary and sufficient conditions for there to be a unique perfect-foresight solution an otherwise linear dynamic model with occasionally binding constraints, given fixed terminal condition. derive further results on existence of in presence such conditions. These give determinacy models much as Blanchard Kahn (1980) did models. In application, we show that widely used Ne...

In considering thunderclap headache, the immediate need is to exclude the possibility of subarachnoid hemorrhage. Both our protagonists agree on this point, that the minimum required is to perform a plain brain CT and, if there is no evidence of hemorrhage, lumbar puncture. We agree with Moussouttas and Mayer that spectrophotometry to detect xanthochromia should be mandatory. It is at this poin...