Monetary Policy and Excessive Bank Risk Taking

If monetary policy is to aim at financial stability, how would it change? To analyze this question, this paper develops a general-form model with endogenous bank risk profiles. Policy rates affect both bank incentives to search for yield and the cost of wholesale funding. Financial stability objectives are then shown to make a monetary authority more conservative and more aggressive. Conservative as it sets higher rates on average. And aggressive because, in reaction to negative shocks, cuts are deeper but shorter-lived than otherwise. Keeping cuts short is crucial as bank risk responds primarily to stable low rates. Within the short span, cuts then must be deep to achieve standard objectives.

More is Less: Perfectly Secure Oblivious Algorithms in the Multi-Server Setting

The problem of Oblivious RAM (ORAM) has traditionally been studied in a single-server setting, but more recently the multi-server setting has also been considered. Yet it is still unclear whether the multi-server setting has any inherent advantages, e.g., whether the multi-server setting can be used to achieve stronger security goals or provably better efficiency than is possible in the single-server case. In this work, we construct a perfectly secure 3-server ORAM scheme that outperforms the best known single-server scheme by a logarithmic factor. In the process, we also show, for the first time, that there exist specific algorithms for which multiple servers can overcome known lower bounds in the single-server setting.Comment: 36 pages, Accepted in Asiacrypt 201

How transparent are central banks?

Central bank transparency has become the topic of a lively public and academic debate on monetary policy. However, this has been complicated by the fact that transparency is a qualitative concept that is hard to measure. This paper proposes an index for the transparency of monetary policy that comprises the political, economic, procedural, policy and operational aspects of central banking. The index is compiled for nine major central banks. It is based on a detailed analysis of actual information disclosure and reveals a rich variety in the degree and dynamics of central bank transparency

Solid variant of aneurysmal bone cyst of the heel: a case report

<p>Abstract</p> <p>Introduction</p> <p>An aneurysmal bone cyst is a benign but often rapidly expanding osteolytic multi-cystic osseous lesion that occurs as a primary, secondary, intra-osseous, extra-osseous, solid or conventional lesion. It frequently coexists with other benign and malignant bone tumors. Although it is considered to be reactive in nature, there is evidence that some aneurysmal bone cysts are true neoplasms. The solid variant of aneurysmal bone cyst is a rare subtype of aneurysmal bone cyst with a preponderance of solid to cystic elements. Such a case affecting the heel, an unusual site, is reported.</p> <p>Case presentation</p> <p>A 26-year-old Caucasian man presented with pain and swelling in his left lower extremity. A plain radiograph demonstrated an intra-osseous, solitary, eccentric mass in the front portion of the left heel. Computed tomography and magnetic resonance imaging scans showed that the lesion appeared to be sub-cortical, solid with a small cystic portion without the characteristic fluid-fluid level detection but with distinct internal septation. Bone images containing fluid-fluid levels are usually produced by aneurysmal bone cysts. The fluid-fluid level due to bleeding within the tumor followed by layering of the blood components based density differences, but it was not seen in our case. An intra-lesional excision was performed. Microscopic examination revealed fibrous septa with spindle cell fibroblastic proliferation, capillaries and extensive areas of mature osteoid and reactive woven bone formation rimmed by osteoblasts. The spindle cells had low mitotic activity, and atypical forms were absent. The histological features of the lesion were consistent with the solid variant of an aneurysmal bone cyst.</p> <p>Conclusion</p> <p>Solid aneurysmal bone cysts have been of great interest to pathologists because they may be mistaken for malignant tumors, mainly in cases of giant cell tumors or osteosarcomas, because of cellularity and variable mitotic activity. It is rather obvious that the correlation of clinical, radiological and histological findings is necessary for the differential diagnosis. The eventual diagnosis is based on microscopic evidence and is made when a predominance of solid to cystic elements is found. The present case is of great interest because of the nature of the neoplasm and the extremely unusual location in which it developed. Pathologists must be alert for such a diagnosis.</p