The Timing and Source of Long-Run Returns Following Repurchases

This paper investigates the timing and source of anomalous positive long-run abnormal returns following repurchase authorizations. Returns between program authorization and completion announcements are indistinguishable from 0. Abnormal returns occur only after completion announcements. Long-run returns are largely attributable to announcement returns at subsequent authorizations and takeover attempts; that is, anomalous post-authorization returns are not persistent drifts but rather step functions. These findings have important implications for prior papers examining this most persistent and widespread anomaly. Further, our results serve to refocus the search for a rational explanation for the anomaly on subsequent repurchase announcements and takeover bids.12 month embargo; Published online: 21 April 2017This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Why Do Firms Disagree with Short Sellers? Managerial Myopia versus Private Information

Though short sellers on average succeed at identifying overvalued equity, firms often signal disagreement with short sellers by repurchasing stock when short interest increases. We investigate whether this disagreement reflects a myopic defense of inflated prices, or positive private information. These repurchases appear motivated by managers' private information, not agency issues, even when managerial benefits to short-termism are enhanced or monitoring is weaker. Managers' informational advantage relates to subsequent news, earnings, and risk, but is attenuated if activists target management or insiders sell. A trading strategy based on our findings earns 7.5% annually.This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Does policy uncertainty affect mergers and acquisitions?

Political and regulatory uncertainty is strongly negatively associated with merger and acquisition activity at the macro and firm levels. The strongest effects are for uncertainty regarding taxes, government spending, monetary and fiscal policies, and regulation. Consistent with a real options channel, the effect is exacerbated for less reversible deals and for firms whose product demand or stock returns exhibit greater sensitivity to policy uncertainty, but attenuated for deals that cannot be delayed due to competition and for deals that hedge firm-level risk. Contractual mechanisms (deal premiums, termination fees, MAC clauses) unanimously point to policy uncertainty increasing the target's negotiating power. Published by Elsevier B.V.36 month embargo; published online: 16 May 2018This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

The Timing and Source of Long-Run Returns Following Repurchases

This paper investigates the timing and source of anomalous positive long-run abnormal returns following repurchase authorizations. Returns between program authorization and completion announcements are indistinguishable from 0. Abnormal returns occur only after completion announcements. Long-run returns are largely attributable to announcement returns at subsequent authorizations and takeover attempts; that is, anomalous post-authorization returns are not persistent drifts but rather step functions. These findings have important implications for prior papers examining this most persistent and widespread anomaly. Further, our results serve to refocus the search for a rational explanation for the anomaly on subsequent repurchase announcements and takeover bids.12 month embargo; Published online: 21 April 2017This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Imaging the Antarctic Ice Sheet Subsurface with the HF GPR TAPIR

An HF impulse polarimetric Ground Penetrating Radar (GPR) operating at very low frequencies (ranging from ~2 to 8MHz) has been developed in the frame of the NetLander mission. This instrument, named TAPIR (Terrestrial And Planetary Investigation by Radar), was designed to probe the Martian subsurface down to kilometric depth and search for potential water reservoirs. Although the NetLander mission was cancelled in 2003, the interest on the exploration of Martian subsurface was recently enhanced by the promising observations of the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) on board of the ESA Mars Express orbiter. In particular, MARSIS detected the base of the North Polar Layered Deposits, penetrating up to ~1.8km the ice-rich upper layer of the underground. Such results suggest that TAPIR, which operates in the same frequency range as MARSIS and can performed a higher number of coherent integrations, is able to reach deeper structures. Yet, in contrast with classical GPRs, TAPIR can not move onto the surface and thus won't provide 2D or 3D scan of the subsurface. To retrieve, in spite of this NetLander restraint, the 3D distribution of the reflecting facets of the underground, the instrument was equipped with two electrical dipoles and a rotating magnetic sensor. These antennas allow to derive, from the measured values of 5 components of the wave field, the direction of arrival of the reflected waves hence the inclination of the buried reflectors. The first validation of this innovative concept was carried out during the RANETA (RAdar of NEtlander in Terre Adélie) campaign organized by the Institute Paul-Emile Victor in January-February 2004. This campaign took place on the Antarctic ice sheet close to the French-Italian Cap Prudhomme station. 8 soundings of the ice shelf were performed on various sites corresponding to different altitudes above the sea level (ranging from ~285m to ~1100m). We shall provide a detailed description of the principle of operation of the radar and of the method of analysis of the observations. The ice-bedrock interface was detected in all of the soundings with clear signals on both electric and magnetic antennas. The measured ice thicknesses show that up to ~ 45 km from the coast the bed-rock stays at an altitude close to the sea level. In several occasions several echoes have been detected and a dedicated data processing algorithm allows to disentangle the various echoes and determine the location of the reflecting facets of the bed-rock. In support to the data analysis, numerical simulations have been conducted using a FDTD method and reproduce the actual observations. These numerical simulations are also used to interpret the frequency profile of the electric antenna and obtain the electromagnetic characteristics of the upper layer of the ice

An Imaging HF GPR Using Stationary Antennas: Experimental Validation Over the Antarctic Ice Sheet

International audienceTerrestrial And Planetary Imaging Radar (TAPIR) is an innovative high-frequency ground-penetrating radar (GPR) developed in the frame of the Martian NetLander mission to probe the subsurface down to kilometric depths. Unlike most GPRs, TAPIR is able to image underground reflectors with stationary antennas. In this paper, after a brief presentation of the instrument, we describe the method developed to interpret data collected during the RAdar of NEtlander in Terre Ade acutelie (RANETA) field survey in Antarctica. This method consists of retrieving the direction of arrival of each detected echo through the measurement of five components of the electromagnetic field (the three magnetic components and the horizontal components of the electric field). Thus, both the range and the direction of each individual reflection or diffraction due to the ice-bedrock interface are resolved. We validated this method on finite-difference time-domain numerically simulated data for different subsurface configurations before applying it to RANETA observations. In particular, the irregular topography of the bedrock in two sounding sites was revealed. We discuss the accuracy of our result