Miracle-dz/UniFAR-FTUs huggingface dataset:
Carry Trades and Currency Crashes

This paper documents that carry traders are subject to crash risk: i.e. exchange rate movements between high-interest-rate and low-interest-rate currencies are negatively skewed. We argue that this negative skewness is due to sudden unwinding of carry trades, which tend to occur in periods in which risk appetite and funding liquidity decrease. Funding liquidity measures predict exchange rate movements, and controlling for liquidity helps explain the uncovered interest-rate puzzle. Carry-trade losses reduce future crash risk, but increase the price of crash risk. We also document excess co-movement among currencies with similar interest rate. Our findings are consistent with a model in which carry traders are subject to funding liquidity constraints.
Spatially resolved spectroscopy of Coma cluster early-type galaxies III. The stellar population gradients ?

Based on Paper I of this series (Mehlert et al. 2000), we derive central values and logarithmic gradients for the H, Mg and Fe indices of 35 early-type galaxies in the Coma cluster. We find that pure elliptical galaxies have on average slightly higher velocity dispersions, lower H, and higher metallic line-strengths than galaxies with disks (S0). The latter form two families, one comparable to the ellipticals and a second one with significantly higher H, and weaker metallic lines. Our measured logarithmic gradients within the eective radius areh4Mg b i 0:037,h4hFeii 0:029,h4H i+0:017 and h4i 0:063. The gradients strongly correlate with the gradients of , but only weakly with the central index values and galaxy velocity dispersion. Using stellar population models with variable element abundance ratios from Thomas et al. (2003a) we derive average ages, metallicities and (=Fe) ratios in the center and at the eective radius. We find that the =Fe ratio correlates with velocity dispersion and drives 30% of the Mg- relation, the remaining 70% being caused by metallicity variations. We confirm previous findings that part of the lenticular galaxies in the Coma cluster host very young (2 Gyr) stellar populations, hence must have experienced relatively recent star formation episodes. Again in accordance with previous work we derive negative metallicity gradients ( 0:16 dex per decade) that are significantly flatter than what is expected from gaseous monolithic collapse models, pointing to the importance of mergers in the galaxy formation history. Moreover, the metallicity gradients correlate with the velocity dispersion gradients, confirming empirically earlier suggestions that the metallicity gradient in ellipticals is produced by the local potential well. The gradients in age are negligible, implying that no significant residual star formation has occurred either in the center or in the outer parts of the galaxies, and that the stellar populations at dierent radii must have formed at a common epoch. For the first time we derive the gradients of the =Fe ratio and find them very small on average. Hence, =Fe enhancement is not restricted to galaxy centers but it is a global phenomenon. Our results imply that the Mg- local relation inside a galaxy, unlike the global Mg- relation, must be primarily driven by metallicity variations alone. Finally we note that none of the stellar population parameters or their gradients depend on the density profile of the Coma cluster, even though it spans 3 dex in density.
Sufficiently myopic adversaries are blind

In this work we consider the communication setting in which a sender, Alice, wishes to communicate with a receiver, Bob, over a channel controlled by an adversarial entity, Calvin, who is myopic. Roughly speaking, for blocklength n, the codeword Xn transmitted by Alice is corrupted by Calvin who must base his adversarial decisions, on which characters of Xn to corrupt and how to corrupt them, not on the entire view of the codeword Xn but on Zn, the image of Xn through a noisy memoryless channel. More specifically, our communication model may be described by two channels. A memoryless channel p(z|x) from Alice to Calvin, and an arbitrarily varying channel from Alice to Bob, p(y|x, s) governed by a states Sn determined by Calvin. In standard adversarial channels, the states Sn may depend on the codeword Xn, however in our setting Sn depends only on Calvin's view Zn. The myopic channel captures a broad range of channels and bridges between the standard models of memoryless and adversarial (zero error) channels. In this work we present upper and lower bounds on the capacity of myopic channels. For a number of special cases of interest we show that our bounds are tight. We extend our results to the setting of secure communication in which we require that the transmitted message remain secret from Calvin. For example, we show that if (i) Calvin may flip at most a p fraction of the bits communicated between Alice and Bob, and (ii) Calvin views Xn through a binary symmetric channel with parameter q, then once Calvin is “sufficiently myopic” (in this case, when q > p), then the optimal communication rate is that of an adversary who is “blind” (that is, an adversary that does not see Xn at all), which is 1-H(p) for standard communication, and H(q)-H(p) for secure communication. A similar phenomena exists for our general model of communication.
Chapter 4 : Additive effects of attention and stimulus contrast in primary visual cortex

Previous studies have proposed a variety of mechanisms by which attention influences neuronal activity. Here we investigated the mechanisms of attention in the striate cortex of monkeys performing a spatial or an object based attention task at various stimulus contrasts and compared neuronal contrast response functions with and without attention. Our data are best described by an additive interaction: the influence of attention on the neuronal response is relatively independent of the stimulus contrast, at least when the stimulus has enough contrast to become visible. This shows that attention adds to the neuronal responses in a largely contrast invariant manner. These data support recent fMRI studies, and suggest that feedback from higher areas exerts a constant attentional drive that is mostly task not stimulus driven.
A NOTE ON PERTURBATION ANALYSIS ESTIMATORS FOR AMERICAN-STYLE OPTIONS

In this note, we correct an error in the paper by Fu and Hu [1] for the perturbation analysis estimator given for the gradient of an American call option payoff on an underlying asset paying multiple dividends. We then introduce a different asset price model that is more straightforward than the previous model, and derive the corresponding gradient estimators. We conclude with a brief discussion of extensions of the estimator to other American-style options.
Transfer of Fourier Multipliers into Schur Multipliers and Sumsets in a Discrete Group

Abstract We inspect the relationship between relative Fourier multipliers on noncommutative Lebesgue–Orlicz spaces of a discrete group $\Gamma$ and relative Toeplitz-Schur multipliers on Schatten–von-Neumann–Orlicz classes. Four applications are given: lacunary sets, unconditional Schauder bases for the subspace of a Lebesgue space determined by a given spectrum $\Lambda \,\subseteq \,\Gamma$ , the norm of the Hilbert transformand the Riesz projection on Schatten–von-Neumann classes with exponent a power of 2, and the norm of Toeplitz Schur multipliers on Schatten–von-Neumann classes with exponent less than 1.
Age-related vulnerability in the neural systems supporting semantic processing

Our ability to form abstract representations of objects in semantic memory is crucial to language and thought. The utility of this information relies both on the representations of sensory-motor feature knowledge stored in long-term memory and the executive processes required to retrieve, manipulate, and evaluate this semantic knowledge in a task-relevant manner. These complementary components of semantic memory can be differentially impacted by aging. We investigated semantic processing in normal aging using functional magnetic resonance imaging (fMRI). Young and older adults were asked to judge whether two printed object names match on a particular feature (for example, whether a tomato and strawberry have the same color). The task thus required both retrieval of relevant visual feature knowledge of object concepts and evaluating this information. Objects were drawn from either natural kinds or manufactured objects, and were queried on either color or shape in a factorial design. Behaviorally, all subjects performed well, but older adults could be divided into those whose performance matched that of young adults (better performers) and those whose performance was worse (poorer performers). All subjects activated several cortical regions while performing this task, including bilateral inferior and lateral temporal cortex and left frontal and prefrontal cortex. Better performing older adults showed increased overall activity in bilateral premotor cortex and left lateral occipital cortex compared to young adults, and increased activity in these brain regions relative to poorer performing older adults who also showed gray matter atrophy in premotor cortex. These findings highlight the contribution of domain-general executive processing brain regions to semantic memory, and illustrate differences in how these regions are recruited in healthy older adults.
Characteristics and Tendencies of First and Second-Generation University Students.

This study examined academic characteristics and tendencies of first-generation and second-generation students. Students at a mid-sized state university in Tennessee were surveyed to determine their preferred learning format, number of hours enrolled, hours applied toward studying outside the classroom, hours working off-campus, and current GPA. Results of the study revealed that first-generation students had slightly higher GPA’s than second-generation students and preferred face-toface instruction over on-line instruction. Researchers noticed that hours studied outside the classroom showed marginally significant differences over all the other categories observed.
Deflating Profitability

Gross profit scaled by book value of total assets predicts the cross-section of average returns. Novy-Marx (2013) concludes that it outperforms other measures of profitability such as bottom-line net income, cash flows, and dividends. One potential explanation for the measure’s predictive ability is that its numerator - gross profit - is a “cleaner” measure of economic profitability. An alternative explanation lies in the measure’s deflator. We find that net income equals gross profit in predictive power when they have consistent deflators. Deflating profit by the book value of total assets results in a variable that is the product of profitability and the ratio of the market value of equity to the book value of total assets, which is priced. We then construct an alternative measure of profitability, operating profitability, which better matches current expenses with current revenue. This measure exhibits a far stronger link with expected returns than either net income or gross profit. It predicts returns as far as ten years ahead, seemingly inconsistent with irrational pricing explanations.
Neuropathy in Parkinson’s Disease Patients with Intestinal Levodopa Infusion versus Oral Drugs

Background Severe polyneuropathy has been observed in a number of patients treated for Parkinson’s disease with Levodopa/Carbidopa intestinal gel infusion. This may reflect a rare individual complication or a systematic side effect. Objective To investigate whether peripheral nerve function differed between patients with oral treatment versus Levodopa/Carbidopa intestinal gel infusion. Methods In an observational design, data from median, tibial, and peroneal neurography were prospectively assessed and compared between patients with conventional drug treatment (n = 15) and with Levodopa/Carbidopa intestinal gel infusion (n = 15). The groups were matched for age and disease duration. In view of the medical risk profile for polyneuropathy, comorbidity and basic serological parameters were assessed. Results Axonal neuropathy was common in both patient groups. However, although group differences in risk factors for polyneuropathy were not evident, neurographic abnormalities were more severe in the patients treated with Levodopa/Carbidopa intestinal gel infusion than in the orally treated patients. In the group with Levodopa/Carbidopa intestinal gel infusion, the degree of neuropathic change correlated with weight lost since therapy initiation and with the drug dose. In contrast to the axonal abnormalities, conduction velocity was found normal in both groups. Conclusion The results are compatible with the promotion of axonal neuropathy by Levodopa/Carbidopa intestinal gel infusion. This could be due to the intrinsically high levodopa doses associated with the therapy and/or malnutritional effects from intestinal drug application. The results should be corroborated by a larger longitudinal and controlled trial.
Exploiting Isochrony in Self-Triggered Control

Event-triggered control and self-triggered control have been recently proposed as new implementation paradigms that reduce resource usage for control systems. In self-triggered control, the controller is augmented with the computation of the next time instant at which the feedback control law is to be recomputed. Since these execution instants are obtained as a function of the plant state, we effectively close the loop only when it is required to maintain the desired performance, thereby greatly reducing the resources required for control. In this paper we present a new technique for the computation of the execution instants by exploiting the concept of isochronous manifolds, also introduced in this paper. While our previous results showed how homogeneity can be used to compute the execution instants along some directions in the state space, the concept of isochrony allows us to compute the executions instants along every direction in the state space. Moreover, we also show in this paper how to homogenize smooth control systems thus making our results applicable to any smooth control system. The benefits of the proposed approach with respect to existing techniques are analyzed in two examples.
Decision-making during a crisis: the interplay of narratives and statistical information before and after crisis communication

Abstract Decision-making during a crisis is affected by several sources of information and prior knowledge, such as factual (statistical) information, narratives of others, and real-time governmental messages. The present study investigated how two types of information (statistics and narratives) influence helping behavior after the occurrence of a traffic accident. We used a scripted crisis scenario in a virtual environment, where several types of behavior could be measured. The main dependent variable was whether participants would move the victim or not. By moving the victim, he would be rescued from a potentially unsafe position (the tilted truck could contain poisonous substances), but moving also entailed a risk of increased injury (according to the statistical information the most likely consequence). Our results indicate that more victims were moved in the narrative condition before an official message was received. Participants who had received statistical information or both types of information performed similar to the control condition. After the official message, informing participants to keep distance, more victims were moved in the narrative condition and in the combined narrative and statistical condition. A narrative therefore has stronger effects when (information about) the actual situation matches the narrative’s content. In contrast with our expectations, affective response did not mediate the relationship between narrative information and moving victims. An alternative explanation would be that narratives trigger a more heuristic way of information processing.
Electronic structure of carbon nanotubes

The remarkable electronic properties that are predicted for carbon nanotubes have been a major reason for the interest in these fullerene molecules. A carbon nanotube can be considered as a single graphene sheet wrapped into a seamless cylinder. Early after their discovery in 1991 [1] it was predicted that nanotubes can be either metallic or semiconducting depending on minor di¤erences of the wrapping angle and diameter [2-4] . In other words, similarly shaped molecules consisting of only one element (carbon) may exhibit dramatically di¤erent electronic properties. Previous experiments on multi-wall and single-wall nanotubes [5-12] did not allow to verify this prediction. Here we present combined scanning tunneling microscopy and spectroscopy results on individual single-wall nanotubes. Atomically resolved images allow to relate the electronic spectra to the wrapping angle and diameter. Carbon nanotubes of various wrapping angles indeed appear to be either metallic or semiconducting as is demonstrated from the tunneling density of states. Nanotubes are expected to be strongly one-dimensional conductors. Van Hove singularities at the onset of one-dimensional energy bands are indeed observed. Gap values are in good agreement with theoretical predictions.
Use of TCE Framework to study IT Sourcing: Over-application or Under-theorizing?

IS discipline has seen a large and growing body of research on IT sourcing, with economic theories informing a large portion of this work. The paper examines use of Transaction Cost Economics (TCE) as a theoretical lens to study IT sourcing decision (internal vs. external). It reviews TCE’s major assumptions, and assesses key constructs of frequency, asset specificity, opportunism, and uncertainty, as to their operationalization and results through a meta-analytic review of selected papers. The clearest evidence is seen in case of production costs, while findings on transaction costs are somewhat inconclusive. Moving the research agenda to co-evolutionary drivers of sourcing as buyers and vendors co-evolve, instead of cost-led determinants, holds potential for future research. Taking a longitudinal process approach to improve understanding of complex phenomena is suggested, given limited understanding from using a ‘reference discipline’ theory.
Federal Reserve Bank of New York Staff Reports a Model of Liquidity Hoarding and Term Premia in Inter-bank Markets a Model of Liquidity Hoarding and Term Premia in Inter-bank Markets

This paper presents preliminary findings and is being distributed to economists and other interested readers solely to stimulate discussion and elicit comments. The views expressed in this paper are those of the authors and are not necessarily reflective of views at the Federal Reserve Bank of New York or the Federal Reserve System. Any errors or omissions are the responsibility of the authors. Abstract Financial crises are associated with reduced volumes and extreme levels of rates for term inter-bank loans, reflected in the one-month and three-month Libor. We explain such stress by modeling leveraged banks' precautionary demand for liquidity. Asset shocks impair a bank's ability to roll over debt because of agency problems associated with high leverage. In turn, banks hoard liquidity and decrease term lending as their rollover risk increases over the term of the loan. High levels of short-term leverage and illiquidity of assets lead to low volumes and high rates for term borrowing. In extremis, inter-bank markets can completely freeze. The views expressed in this paper are those of the authors and do not necessarily reflect the position of the Federal Reserve Bank of New York or the Federal Reserve System.
Covariant Representations of C*-dynamical systems Involving Compact Groups

Adviser: Allan Donsig Given a C *-dynamical system (A, G, σ) the crossed product C *-algebra A× σ G encodes the action of G on A. By the universal property of A × σ G there exists a one to one correspondence between the set all covariant representations of the system (A, G, σ) and the set of all *-representations of A × σ G. Therefore, the study of representations of A × σ G is equivalent to that of covariant representations of (A, G, σ). We study induced covariant representations of systems involving compact groups. We prove that every irreducible (resp. factor) covariant representation of (A, G, σ) is induced from an irreducible (resp. factor) representation of a subsystem (A, G 0 , σ) where π 0 is a factor representation. This extends a result obtained in [3] for finite groups. It was shown in [10] that if G is an amenable group then every primitive ideal of A × σ G is induced from a stability group. If G is compact then we obtain a stronger result, that is, every irreducible representation of (A, G, σ) is induced from a stability group. In addition, we show that (A, G, σ) satisfies the strong-EHI property introduced by Echterhoff and Williams in [5]. iii ACKNOWLEDGMENTS I would like to express my immense gratitude to my advisor Allan Donsig who has guided me through writing of this dissertation. He has been a great mentor with whom I could share my academic and non academic concerns. I will always remain indebted to him. I want to thank David Pitts for his input and comments regarding this dissertation. I learned a great deal from David Pitts both in and outside the classroom. He set high expectations and motivated me to do my best in graduate school. I want to thank the entire faculty and staff of the department that helped me succeed as a graduate student. I want to thank Jesse Burke and David Mccune for providing me with a unique roommate and officemate experience. I want to thank my wife for whipping me into a serious student and allowing me to sleep when our daughter would wake up at night.
On LQG joint optimal scheduling and control under communication constraints

In this paper, we consider a discrete-time stochastic system, where sensor measurements are sent over a network to the controller. The design objective is a non-classical multicriterion optimization problem for finite horizon, where the cost function consists of the linear quadratic cost reflecting the control performance and a communication cost penalizing information exchange between sensor and controller. It is shown that the joint optimization of scheduling and control can be separated into three subproblems: an optimal regulator problem, an estimation problem and an optimal scheduling problem. The obtained results are extended to TCP-like networks with random packet loss. In the proposed framework, we classify three classes of schedulers, a purely randomized, a deterministic and a state-dependent scheme, and compare their performance by a numerical example.