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In order to better understand the sources, sinks, and hydrodynamic influences on particulate matter distribution and variability in Arctic basins, we combined transmissometer data from two 2015 fall expeditions: one from Bering Strait (USCGC Healy) and the other from Barents Sea (R/V Polarstern) meeting at the North Pole. These first trans-Arctic sections of beam attenuation were overlain by salinity, temperature, and chlorophyll-a fluorescence (Chl-a) contours. Chl-a sections were overlain by nitrate contours. Particle composition analyzed from filtered samples throughout the full water column aided significantly in discerning sources, distribution, and dynamics of particles. Dense Pacific water moving swiftly through Bering Strait erodes and carries sediment-laden waters onto the Chukchi Shelf and into the Canada Basin. This nutrient-rich Pacific water sinks below a low-salinity, nutrient-poor polar mixed layer, forming a thick lens of high salinity water known as Pacific halocline water (salinity 31-33). Ice and the nutrient-poor mixed layer inhibit photosynthesis in surface waters of Canada and Makarov Basins, but subsurface chlorophyll-a maxima are observed if nutrients and light are available. Surface-water biomass is greater in the Barents Sea than in the Beaufort Gyre because nutrient-rich Atlantic water entering Barents Sea is not isolated from surface waters by ice or strong stratification. Surface water cools, creating high-density water that cascades into ~400 m basins in Barents Sea and into deep Nansen Basin, eroding sediment that creates patches of nepheloid layers in the shallow basins. Intense nepheloid layers in the deep basins are rare, suggesting weak bottom currents. [ABSTRACT FROM AUTHOR]

The article examines Honduras as a test case for evaluating the theory that a small nation with a fixed exchange rate can influence, but not control, the level of its money supply. Equations for the real and nominal demand for money are derived, as well as those for standard reserve flow with and without linear homogeneity in prices. Regressions are then run for annual Honduran data from 1950 through 1974. Results indicate that the Central Bank of Honduras cannot control the long-term level of its money stock.

The article comments on research by John Burt, Fred R. Kaen, and G. Geoffrey Booth--which is referred to as the BKB model--concerning foreign exchange market efficiency and the effectiveness of central bank interventions in stabilizing exchange rates. The spot exchange markets for Canadian dollars, German marks and British pounds are discussed, as well as a hypothesis that efficient market theory does not apply to the Canadian dollar because daily price variance did not fully respond to new information. Central bank intervention, institutional aspects of the Canadian exchange market are not believed to be the reason for the lack of efficacy in price changes. The conclusion is that the BKB model is not relevant to Canada.

We present Lu-Hf dates from multiple growth zones within two large garnet porphyroblasts by a micro-sampling method. A single eclogite sample, taken from the Huwan shear zone in the Hong'an orogen, was investigated with Lu-Hf geochronology by micro-sampling and traditional bulk separation methods. The sample contains a few large garnet porphyroblasts up to several centimetres in diameter and a second major population of smaller (0.1-2.0 mm) garnet porphyroblasts, comprised of dark cores and pale rims. Elemental compositions and mineral inclusions in the garnet appear consistent with two garnet generations. Lu-Hf dates ( c. 400-264 Ma) were determined from twelve micro-sawed garnet sections from two large garnet porphyroblasts. These Lu-Hf dates overlap with age peaks defined by 115 SIMS zircon U-Pb analyses from the same eclogite sample. Bulk analyses of smaller garnet separates define a minimum date of c. 306 Ma and a maximum date of c. 252 Ma for the dark cores and pale rims respectively. These Lu-Hf dates were interpreted to bracket the period of garnet growth and the broad interval from c. 400 to 264 Ma is best explained by protracted and episodic garnet growth, which may require that these rocks experienced two subduction cycles that were initiated during the Devonian and terminated in the Triassic. [ABSTRACT FROM AUTHOR]

Following the financial crisis of 2008, it has been argued that Value at Risk (VaR), and risk analysis in general, failed to alert risk managers of the turbulence on the horizon. This is a misguided view that should not have come as a surprise because many widely circulated academic papers and discussions suggested, well before the crisis, that simple VaR results could easily be misinterpreted if the circumstances for its proper use are not fully understood. This paper addresses some ways in which VaR concepts may be applied more effectively. Non-standard Monte Carlo simulations are utilized. Whereas standard mean–variance defined methodologies using Monte Carlo analysis may not capture how “fat” a lower tail may actually be, a bi-modal switching structure between assumed normal periods and possible turbulent economic periods may help resolve the problem. Lower boundaries (worst case paths) of the different (normal versus bi-modal) processes are mapped to illustrate implied riskiness of portfolios if turbulence occurs. The analysis implies that no mechanical risk analysis is sufficiently divorced from a judgment call about possible market disruptions; however, a bi-modal approach allows quantification of the said judgment in conjunction with empirical observations from history. [ABSTRACT FROM AUTHOR]

Abstract: Markowitz (1952, 1959) underlies modern corporate finance literature, from modern portfolio theory, option theory, to risk management (especially value at risk type methodologies). From it, Diversify has entered all languages, such is its power. Terms such as “the only free lunch” have become a way to give praise to Markowitz work. And, just as with all fundamental breakthroughs in the literature it has been extended many directions, sometimes not necessarily to the benefit of the original work, which often gets blamed when one rendition or another breaks down. With almost every MBA graduated believing they know what Markowitz optimization or portfolio theory means, it behooves us to step back and look at some of the basics, the assumptions that are made, the costs of breaking assumptions, and the potential disasters that can occur when those basics behind all of the theories dependent upon Markowitz'' original work are ignored. This paper lays out many of the basic underlying assumptions behind creation of Markowitz type portfolios, why they matter, and where those assumptions are ignored and/or broken. Breaking model assumptions is common in actual application of theory. Not understanding the implications of broken assumptions is almost a guarantee of failure for a money manager; it is just a matter of time. As one often hears, “Wall Street (or the City if in Europe) is littered with great ideas that do not work in practice.” Some people throw Markowitz and portfolio optimization into that litter bin. We discuss several basic assumptions of modern portfolio theory, when and why they are commonly broken by the best of us in academia and in practice, and discuss the implications for breaking them under trying circumstances. [Copyright &y& Elsevier]

Examines a barrier option theoretic approach to analyzing the potential for losses of a leveraged investor. Risk of a particular style of investment when dealing with hedge funds; Impact of the leverage on the probability of encountering a loss; Simulation of the risk of ruin for an investment fund.

Provides information on the problems and biases inherent in using total returns versus excess returns in means-variance optimization. Practice of currency hedging by securities managers; Implication of large costs to nondomestic investing for the portfolios; Difference between excess and total returns.

Focuses on the problem of using Value at risk (VaR) as a risk management tool for asset managers. Range of routine gains and losses; Monte Carlo method for estimating VaR; Application of elementary statistical models of both financial and physical processes.

In this paper we (1) analyzed a possible bias which may be entered into estimated coefficients in reduced form reserve flow and exchange rate determination equations of the general monetary approach, (2) showed one method of solving the bias problem, (3) provided new empirical evidence on the monetary approach and (4) found that consideration of the bias improved statistical results. Noting the reasons for the possible bias in earlier empirical studies, we used Mexican annual data (for the fixed exchange rate period) and quarterly data on the U.K. and Italy (for the flexible rate period) to show that even when the assumption of equal real income elasticities of money demand at home and abroad cannot be rejected, it is useful to examine various coefficients allowing the income elasticities to differ. This was accomplished by estimating reserve flow and exchange rate determination equations by first estimating the relevant money demand equations and then using the derived income elasticities to adjust the combined (differential) income series as to reduce the bias introduced by the income elasticities assumption. Further, substantiating the monetary model's usefulness in explaining exchange market behavior, tests for the UK which alleviate a recurring multi-colinearity problem were performed. In examining the results of the exchange rate model for the U.K. and Italy, we presented examples where the bias mentioned above was meaningful for one country and not another. This evidence suggests that our methodology for examining exchange rate equations should be considered by monetary approach modelers. More importantly, these results indicate that authors who utilize this type of analysis for balance of payments or exchange rate determination must be doubly careful about elasticity assumptions when dealing with countries whose income elasticities of money demand differ significantly.
Finally, this paper adds new empirical weight to the validity of the monetary... [ABSTRACT FROM AUTHOR]

Explores the use of mean variance portfolio optimization techniques in hedging corporate risks. Use of modern portfolio management techniques to manage corporate risks advantageous to some firms; Analysis of a synthetic European firm exhibiting many of the risks and qualities apropos a firm deciding to utilize mean-variance techniques to manage financial risks.

This article attempts to assess the influence of Great Britain's fiscal deficit on its money stock using quarterly observations for the period 1963-76. The public sector deficit is widely recognized to exercise important influence on the stock of money, either directly or indirectly. The extent of this influence depends on the method of financing the deficit. Specifically, if the deficit is financed by domestic or external non-monetary borrowing the money stock will remain essentially unaffected, but if it is financed through the banking system, ceteris paribus, the money stock will increase. In a framework where monetary policy decisions are made independently of fiscal policy decisions, the monetary authorities, through the relevant credit policy decisions, determine the level of government debt purchases by the non-bank private sector, while the fiscal authorities are left to finance the residual. For example, the Federal Reserve System can adjust its portfolio so as to offset bank purchases of government bonds. By contrast, if monetary policy is passive with respect to fiscal policy, credit policy decisions and the level of government debt purchases are directly linked to the deficit since the full amount of it must he financed by the monetary authorities.