HEDGE FUND REPLICATION STRATEGIES: THE GLOBAL MACRO CASE

This paper performs and analyzes hedge fund replication strategies using liquid exchange-traded instruments to build linear multi-factor models (“clones”) that mimic Hedge Funds returns. First, we follow Hasanhodzic and Lo (2006) six-factor model, using Barclay Hedge Indexes monthly returns for the period of January 1997 to August 2017 on seventeen hedge fund strategies. Next, we introduce variations and new propositions to the model in order to obtain closer risk-return characteristics, focusing on one particular hedge fund strategy: Global Macro. Finally, we use these results to base our conclusion and propose applications for this method.Our findings promote the use of shorter month period in rolling-windows approach and monthly rebalancing strategy for a faster reaction and adaptation to market conditions. Also, it suggests the addition of a strategic-specific factor to obtain better expected-return replications. These findings are particularly relevant to institutional investors that need diversification and could benefit from this asset class exposure, but many times are restricted from investing in hedge funds due to their high fee structure, illiquidity, and opaque tactics

Effect of hydrofracking fluid on colloid transport in the unsaturated zone

Hydraulic fracturing is expanding rapidly in the US to meet increasing energy demand and requires high volumes of hydrofracking fluid to displace natural gas from shale. Accidental spills and deliberate land application of hydrofracking fluids, which return to the surface during hydrofracking, are common causes of environmental contamination. Since the chemistry of hydrofracking fluids favors transport of colloids and mineral particles through rock cracks, it may also facilitate transport of in situ colloids and associated pollutants in unsaturated soils. We investigated this by subsequently injecting deionized water and flowback fluid at increasing flow rates into unsaturated sand columns containing colloids. Colloid retention and mobilization was measured in the column effluent and visualized in situ with bright field microscopy. While <5% of initial colloids were released by flushing with deionized water, 32–36% were released by flushing with flowback fluid in two distinct breakthrough peaks. These peaks resulted from 1) surface tension reduction and steric repulsion and 2) slow kinetic disaggregation of colloid flocs. Increasing the flow rate of the flowback fluid mobilized an additional 36% of colloids, due to the expansion of water filled pore space. This study suggests that hydrofracking fluid may also indirectly contaminate groundwater by remobilizing existing colloidal pollutants

Reverse engineering of biochar

This study underpins quantitative relationships that account for the combined effects that starting biomass and peak pyrolysis temperature have on physico-chemical properties of biochar. Meta-data was assembled from published data of diverse biochar samples (n = 102) to (i) obtain networks of intercorrelated properties and (ii) derive models that predict biochar properties. Assembled correlation networks provide a qualitative overview of the combinations of biochar properties likely to occur in a sample. Generalized Linear Models are constructed to account for situations of varying complexity, including: dependence of biochar properties on single or multiple predictor variables, where dependence on multiple variables can have additive and/or interactive effects; non-linear relation between the response and predictors; and non-Gaussian data distributions. The web-tool Biochar Engineering implements the derived models to maximize their utility and distribution. Provided examples illustrate the practical use of the networks, models and web-tool to engineer biochars with prescribed properties desirable for hypothetical scenarios

Today’s University Students and Their Need to Connect

Higher education is rapidly changing and university instructors are presented with new types of students for whom technology is a significant influence. They perceive technology as a way of life and express a need to feel connected at all times. With increasingly diverse university classroom, technology integration is both a challenge and an opportunity. Supportive communication is important in the promotion of relationships and essential in a university classroom. A convenience sample of 390 students was surveyed to investigate the perceived influences of technology on relationships, including preferences, usage and time with technologies. Results indicated that technology makes communication easier, allows students to stay in touch with more people, and have relationships that would otherwise not be possible. Implications of this study suggest positive influences of technology on academic work, performance and maintenance of relationships. However, disadvantages with using technology such as increased stress, addictive feelings toward technologies, and increased misunderstandings in relationships and conflict also exist

α/β-Ni(OH)₂ phase control by F-ion incorporation to optimise hybrid supercapacitor performance

We have controlled the formation of flower-like nanostructured pure alpha phase and pure beta phase nickel hydroxide (α-Ni(OH)2, β-Ni(OH)2), as well as mixtures of phases (αβ-Ni(OH)2). Through a range of experiments, we prove that the addition of fluoride ions controls the phase formed and we suggest two possible mechanisms for this effect. Incorporated fluoride ions in the layers disfavour the insertion of other anions and water molecules, resulting in β-Ni(OH)2 which has a smaller interlayer distance; and we suggest that the high electronegativity of F results in less nickel oxidation to Ni3+ also disfavouring extra anions between layers. The nickel hydroxide materials were characterised by a suite of techniques including powder X-ray diffraction, electron microscopy, thermal analysis and in situ X-ray absorption spectroscopy, in combination with electrochemical studies. The redox cycle stability and conductivity were improved through control of phase formation, such that αβ-Ni(OH)2 exhibits 108% capacity retention after 2000 continuous charge-discharge cycles at 20 mA cm−1 while α-Ni(OH)2 displays only 50% capacity retention after 2000 cycles. Finally, the assembled αβ-Ni(OH)2//activated carbon hybrid supercapacitor displays maximum energy density of 32 W h kg−1 at a power density of 900 W kg−1, and retains 86% capacity after 5000 continuous charge-discharge cycles.</p

Interethnic differences in pancreatic cancer incidence and risk factors: The Multiethnic Cohort.

While disparity in pancreatic cancer incidence between blacks and whites has been observed, few studies have examined disparity in other ethnic minorities. We evaluated variations in pancreatic cancer incidence and assessed the extent to which known risk factors account for differences in pancreatic cancer risk among African Americans, Native Hawaiians, Japanese Americans, Latino Americans, and European Americans in the Multiethnic Cohort Study. Risk factor data were obtained from the baseline questionnaire. Cox regression was used to estimate the relative risks (RRs) and 95% confidence intervals (CIs) for pancreatic cancer associated with risk factors and ethnicity. During an average 16.9-year follow-up, 1,532 incident pancreatic cancer cases were identified among 184,559 at-risk participants. Family history of pancreatic cancer (RR 1.97, 95% CI 1.50-2.58), diabetes (RR 1.32, 95% CI 1.14-1.54), body mass index ≥30&nbsp;kg/m2 (RR 1.25, 95% CI 1.08-1.46), current smoking (&lt;20 pack-years RR 1.43, 95% CI 1.19-1.73; ≥20 pack-years RR 1.76, 95% CI 1.46-2.12), and red meat intake (RR 1.17, 95% CI 1.00-1.36) were associated with pancreatic cancer. After adjustment for these risk factors, Native Hawaiians (RR 1.60, 95% CI 1.30-1.98), Japanese Americans (RR 1.33, 95% CI 1.15-1.54), and African Americans (RR 1.20, 95% CI 1.01-1.42), but not Latino Americans (RR 0.90, 95% CI 0.76-1.07), had a higher risk of pancreatic cancer compared to European Americans. Interethnic differences in pancreatic cancer risk are not fully explained by differences in the distribution of known risk factors. The greater risks in Native Hawaiians and Japanese Americans are new findings and elucidating the causes of these high rates may improve our understanding and prevention of pancreatic cancer

Integrated processing method for microseismic signal based on deep neural network

Denoising and onset time picking of signals are essential before extracting source information from collected seismic/microseismic data. We proposed an advanced deep dual-tasking network (DDTN) that integrates these two procedures sequentially to achieve the optimal performance. Two homo-structured encoder–decoder networks with specially designed structures and parameters are connected in series for handling the denoising and detection of microseismic signals. Based on the similarity of data types, the output of the denoising network will be imported into the detection network to obtain labels for the signal duration. The procedures of denoising and duration detection can be completed in an integrated way, where the denoised signals can improve the accuracy of onset time picking. Results show that the method has a good performance for the denoising of microseismic signals that contain various types and intensities of noise. Compared with existing methods, DDTN removes the noise with a minor waveform distortion. It is ideal for recovering the microseismic signal while maintaining a good capacity for onset time picking when the signal-to-noise ratio is low. Based on that, the second network can detect a more accurate duration of microseismic signals and thus obtain more accurate onset time. The method has great potential to be extended to the study of exploration seismology and earthquakes

Evaluating causal effects on time-to-event outcomes in an RCT in Oncology with treatment discontinuation due to adverse events

In clinical trials, patients sometimes discontinue study treatments prematurely due to reasons such as adverse events. Treatment discontinuation occurs after the randomisation as an intercurrent event, making causal inference more challenging. The Intention-To-Treat (ITT) analysis provides valid causal estimates of the effect of treatment assignment; still, it does not take into account whether or not patients had to discontinue the treatment prematurely. We propose to deal with the problem of treatment discontinuation using principal stratification, recognised in the ICH E9(R1) addendum as a strategy for handling intercurrent events. Under this approach, we can decompose the overall ITT effect into principal causal effects for groups of patients defined by their potential discontinuation behaviour in continuous time. In this framework, we must consider that discontinuation happening in continuous time generates an infinite number of principal strata and that discontinuation time is not defined for patients who would never discontinue. An additional complication is that discontinuation time and time-to-event outcomes are subject to administrative censoring. We employ a flexible model-based Bayesian approach to deal with such complications. We apply the Bayesian principal stratification framework to analyse synthetic data based on a recent RCT in Oncology, aiming to assess the causal effects of a new investigational drug combined with standard of care vs. standard of care alone on progression-free survival. We simulate data under different assumptions that reflect real situations where patients' behaviour depends on critical baseline covariates. Finally, we highlight how such an approach makes it straightforward to characterise patients' discontinuation behaviour with respect to the available covariates with the help of a simulation study

A new method to synthesize very active and stable supported metal Pt catalysts: thermo-destabilization of microemulsions

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.A new technique to deposit nanoparticles synthesized in reverse micellar microemulsions onto support material without agglomeration is named thermal destabilization of microemulsion. The multifaceted Pt crystals, mostly truncated octahedra, were produced inside reverse micelles with an average size of 2.5 nm and a narrow size distribution. After deposition, the Pt crystals were found to be well dispersed on the support with an average size of 2.5 nm. After testing with hydrogenation of α-methyl styrene, the produced Pt-catalyst showed higher activity (6 times higher) and stability than commercial ones. The advantages of this synthesis route of nanoparticles include simple operation, and the ease of controlling the size and shape of nanoparticles without using capping agents.DFG, EXC 314, Unifying Concepts in Catalysi