Standard-Nutzungsbedingungen:Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden.Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen.Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, gelten abweichend von diesen Nutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte. Terms of use: Documents in AbstractThis study describes the Indian corporate governance system and examines how the system has both supported and held back India's ascent to the top ranks of the world's economies. While on paper the country's legal system provides some of the best investor protection in the world, enforcement is a major problem with slow, over-burdened courts and significant corruption.

Background: Open surgical closure and small-bore suture-based preclosure devices have limitations when used for transcatheter aortic valve replacement, percutaneous endovascular abdominal aortic aneurysm repair, or percutaneous thoracic endovascular aortic aneurysm repair. The MANTA vascular closure device is a novel collagen-based technology designed to close large bore arteriotomies created by devices with an outer diameter ranging from 12F to 25F. In this study, we determined the safety and effectiveness of the MANTA vascular closure device. Methods and Results: A prospective, single arm, multicenter investigation in patients undergoing transcatheter aortic valve replacement, percutaneous endovascular abdominal aortic aneurysm repair, or thoracic endovascular aortic aneurysm repair at 20 sites in North America. The primary outcome was time to hemostasis. The primary safety outcomes were accessed site-related vascular injury or bleeding complications. A total of 341 patients, 78 roll-in, and 263 in the primary analysis cohort, were entered in the study between November 2016 and September 2017. For the primary analysis cohort, transcatheter aortic valve replacement was performed in 210 (79.8%), and percutaneous endovascular abdominal aortic aneurysm repair or thoracic endovascular aortic aneurysm repair was performed in 53 (20.2%). The 14F MANTA was used in 42 cases (16%), and the 18F was used in 221 cases(84%). The mean effective sheath outer diameter was 22F (7.3 mm). The mean time to hemostasis was 65±157 seconds with a median time to hemostasis of 24 seconds. Technical success was achieved in 257 (97.7%) patients, and a single device was deployed in 262 (99.6%) of cases. Valve Academic Research Consortium-2 major vascular complications occurred in 11 (4.2%) cases: 4 received a covered stent (1.5%), 3 had access site bleeding (1.1%), 2 underwent surgical repair (0.8%), and 2 underwent balloon inflation (0.8%). Conclusions: In a selected population, this study demonstrated that the MANTA percutaneous vascular closure device can safely and effectively close large bore arteriotomies created by current generation transcatheter aortic valve replacement, percutaneous endovascular abdominal aortic aneurysm repair, and thoracic endovascular aortic aneurysm repair devices. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02908880.

b)), and Arditti, Ayadin, Mattu, and Rigskee (1986) documents the existence of substantial and sustained deviations between actual stock index futures prices and theoretical values. Based on these findings, Merrick (1989) and Finnerty and Park (1988) attempt to demonstrate the profitability of arbitrage related program trading strategies. On the other hand, Saunders and Mahajan (1988) adopt an alternative approach and conclude that stock index futures are priced efficiently.One limitation of empirical work in this area is that it relates only to stock index futures contracts traded within the USA. The fact that earlier work involves repeated analysis of data sets pertaining to the same economic and institutional environment, albeit for different sample periods, means that (whilst the work is of great interest and enables a better understanding of index futures contract pricing to be developed) it needs to be externally validated.A second limitation of earlier empirical work in this area is that even though there appears to be a broad consensus that observed mispricing is often sufficient to span the transaction cost bounds and offer arbitrage possibilities, this is not substantiated with formal evidence on actual transaction costs. In this respect the evidence of Stoll and Whaley (1987) is largely anecdotal, while Merrick (1989) uses an ad hoc estimate and Finnerty and Park (1988) ignore transaction costs.This article seeks to partially bridge these "gaps" in the literature by reporting the results of a comprehensive analysis of a totally new set of data relating to the UK FTSE-100 stock index futures contract traded on the London International Financial Futures Exchange (LIFFE). The results are set into perspective by an analysis of the relevant transaction costs. To provide direct comparability with previous work, the present study seeks to replicate, as closely as possible, many of the tests The authors acknowledge the financial assistance of the Center for the Study of Futures Markets, Columbia University. They are grateful for comments received from Michael Brennan, and participants at conferences and seminars at the universities of Edinburgh, Dundee, Wales, Warwick, and the London School of Economics. The authors are also grateful to the Institute of Quantitative Investment Research (INQUIRE) for their encouragement in the form of the prize for the best paper at the annual conference, Brighton, October 1989. Any remaining errors are, of course, the responsibility of the authors. Pradeep K . Yadav is a lecturer in.'It is diflicult to select a stochastic process to "model" mispricing. Brennan and Schwartz (1987) suggest a Brownian Bridge process. But this is path independent, when the empirical evidence of Mackinlay and Ramaswamy (1987) indicates that the mispricing series is path dependent.2Garbade and Silber (1983) call this factor 6. STOCK INDEX FUTURES ARBITRAGE/ 577

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Standard-Nutzungsbedingungen:Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden.Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen.Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, gelten abweichend von diesen Nutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte. Terms of use: Documents in The information content of implied volatilities and model-free volatility expectations: Evidence from options written on individual stocks AbstractThe volatility information content of stock options for individual firms is measured using option prices for 149 U.S. firms and the S&P 100 index. ARCH and regression models are used to compare volatility forecasts defined by historical stock returns, at-the-money implied volatilities and model-free volatility expectations for every firm. For one-day-ahead estimation, a historical ARCH model outperforms both of the volatility estimates extracted from option prices for 36% of the firms, but the option forecasts are nearly always more informative for those firms that have the more actively traded options. When the prediction horizon extends until the expiry date of the options, the option forecasts are more informative than the historical volatility for 85% of the firms. However, the model-free volatility expectations are generally outperformed by the at-the-money implied volatilities.2