Forecasting volatility in commodity markets

Commodity prices have historically been among the most volatile of international prices. Measured volatility (the standard deviation of price changes) has not been below 15 percent and at times has been more than 50 percent. Often the volatility of commodity prices has exceeded that of exchange rates and interest rates. The large price variations are caused by disturbances in demand and supply. Stockholding leads to some price smoothing, but when stocks are low, prices can jump sharply. As a result, commodity price series are not stationary and in some periods they jump abruptly to high levels or fall precipitously to low levels relative to their long-run average. Thus it is difficult to determine long-term price trends and the underlying distribution of prices. The volatility of commodity prices makes price forecasting difficult. Indeed, realized prices often deviate greatly from forecasted prices, which has led to the practice of giving forecasts probability ranges. But assigning probability ranges requires forecasting future price volatility, which, given uncertainties about true price distribution, is difficult. One potentially useful source of information for forecasting volatility is the volatility forecasts imbedded in the prices of options written on commodities traded in exchanges. Options give the holder the right to buy (call) or sell (put) a certain commodity at a certain date at a fixed (exercise) price. Options prices depend on several variables, one of which is the expected volatility up to the maturity date. Given a specific theoretical model, the market prices of options can be used to derive the market's expectations about price volatility and the price distribution. The authors systematically analyze different methods'abilities to forecast commodity price volatility (for several commodities). They collected the daily prices of commodity options and other variables for seven commodities (cocoa, corn, cotton, gold, silver, sugar, and wheat). They extracted the volatility forecasts implicit in options prices using several techniques. They compared several volatility forecasting methods, divided into three categories: (1) forecasts using only expectations derived form options prices; (2) forecasts using only time-series modeling; (3) forecasts that combine market expectations and time-series modeling (a new method devised for this purpose). They find that the volatility forecasts produced by method 3 outperform the first two as well as the naive forecast based on historical volatility. This result holds both in and out of sample for almost all commodities considered.Markets and Market Access,Access to Markets,Economic Theory&Research,Economic Forecasting,Science Education

Changing from Traditional Practice to a New Model for Preparing Future Leaders

In dramatic departure from the traditional format of programs preparing building level leaders, in the last sixteen years the Educational Leadership Department in the College of Education at Kansas State University (KSU) has worked with eight different partners in designing and delivering site-based customized 30-hour master’s degree programs in educational leadership to 19 individual cohorts

Disentangling hadronic from leptonic emission in the composite SNR G326.3−-1.8

G326.3$-$1.8 (also known as MSH 15$-$56) has been detected in radio as a middle-aged composite supernova remnant (SNR) consisting of an SNR shell and a pulsar wind nebula (PWN), which has been crushed by the SNR's reverse shock. Previous $\gamma$-ray studies of SNR G326.3$-$1.8 revealed bright and extended emission with uncertain origin. Understanding the nature of the $\gamma$-ray emission allows probing the population of high-energy particles (leptons or hadrons) but can be challenging for sources of small angular extent. With the recent $\textit{Fermi}$ Large Area Telescope data release Pass 8, we investigate the morphology of this SNR to disentangle the PWN from the SNR contribution. We perform a morphological and spectral analysis from 300 MeV to 300 GeV. We use the reconstructed events with the best angular resolution to separately investigate the PWN and the SNR emissions, which is crucial to accurately determine the spectral properties of G326.3$-$1.8 and understand its nature. The centroid of the $\gamma$-ray emission evolves with energy and is spatially coincident with the radio PWN at high energies (E $>$ 3 GeV). The morphological analysis reveals that a model considering two contributions from the SNR and the PWN reproduces the $\gamma$-ray data better than a single-component model. The associated spectral analysis using power laws shows two distinct spectral features, a softer spectrum for the remnant ($\Gamma$ = 2.17 $\pm$ 0.06) and a harder spectrum for the PWN ($\Gamma$ = 1.79 $\pm$ 0.12), consistent with hadronic and leptonic origin for the SNR and the PWN respectively. Focusing on the SNR spectrum, we use one-zone models to derive some physical properties and, in particular, we find that the emission is best explained with a hadronic scenario in which the large target density is provided by radiative shocks in HI clouds struck by the SNR

Reports of Committees

Contains reports of the following committees: Annotations to the Restatement of Law, Cooperation with the American Bar Association, Discipline and Disbarment, Federal Legislation, Law Enforcement, Law Examiners, Legal Educaton, Legal Ethics, Legislative, Public Relations, Selection of Judges, and Unauthorized Practice of Law. Also includes the auditor\u27s report

Accessing Young Black Stroke Survivors for Secondary Prevention

ABSTRACT Background- Stroke rates and risk factors may be increasing in young adults aged 18-64, especially black individuals. We sought to identify whether young high risk stroke survivors could be found at community health centers. Methods- This was a cross-sectional analysis of the National Ambulatory Medical Care Survey from 2006-2011. We used chi-square analyses, t-tests, and proportions to compare and describe stroke survivor visits at community health centers and private offices. Results- Young stroke survivor visits comprise 48% of stroke survivor visits at community health centers compared to 31% of stroke survivor visits at the private office setting. Among young stroke survivors cared for at community health centers, 47% were black individuals compared to 14% at a private office setting. The prevalence of hypertension and cigarette smoking was higher in young stroke survivors at the community health center. Conclusions- The community health center is a setting to access young black stroke survivors. Stroke prevention and preparedness interventions should be considered at community health centers

CNN Architectures for Large-Scale Audio Classification

Convolutional Neural Networks (CNNs) have proven very effective in image classification and show promise for audio. We use various CNN architectures to classify the soundtracks of a dataset of 70M training videos (5.24 million hours) with 30,871 video-level labels. We examine fully connected Deep Neural Networks (DNNs), AlexNet [1], VGG [2], Inception [3], and ResNet [4]. We investigate varying the size of both training set and label vocabulary, finding that analogs of the CNNs used in image classification do well on our audio classification task, and larger training and label sets help up to a point. A model using embeddings from these classifiers does much better than raw features on the Audio Set [5] Acoustic Event Detection (AED) classification task.Comment: Accepted for publication at ICASSP 2017 Changes: Added definitions of mAP, AUC, and d-prime. Updated mAP/AUC/d-prime numbers for Audio Set based on changes of latest Audio Set revision. Changed wording to fit 4 page limit with new addition

Ex vivo expansion of megakaryocyte precursors from umbilical cord blood CD34+ cells in a closed liquid culture system

AbstractUmbilical cord blood (UCB) provides a rich source of stem cells for transplantation after myeloablative therapy. One major disadvantage of UCB transplantation is delayed platelet engraftment. We propose to hasten platelet engraftment by expanding the number of megakaryocyte (MK) precursors (CD34/CD41 cells) through cytokine stimulation within a closed, pre-clinical liquid culture system. Clinical engraftment data suggest a 5- to 10-fold increase in MK precursors in a UCB unit can accelerate platelet engraftment, so this was our goal. Thirteen UCB samples from full-term births were Ficoll-separated and frozen for subsequent use. On thawing, the mononuclear cell population was positively selected for CD34+ expression. The cells were cultured in gas-permeable Teflon-coated bags in serum-free medium containing the following cytokines: recombinant human interleukin-3, recombinant human Flt3 ligand, recombinant human stem cell factor, and recombinant human thrombopoietin. MK lineage cell expansion was assessed using mononuclear cell count and flow cytometry (CD34/41, CD41, CD34/61, and CD61 expression) on days 7, 11, and 14. Optimal expansion of CD34/41 and CD41 cells was observed at day 11, with a median 6-fold and 33-fold increase in the starting cell doses, respectively. CD34/61 and CD61 cell expansion at day 11 was 7-fold and 14-fold, respectively. MK precursors can be successfully expanded from CD34+ UCB cells in a closed liquid culture system using interleukin-3, recombinant human Flt3 ligand, recombinant human stem cell factor, and recombinant human thrombopoietin to a level that should have a clinical impact in the transplantation setting. Our ex vivo expansion technique needs to be further optimized before it can be used in a pilot UCB transplantation trial. © 2003 American Society for Blood and Marrow TransplantationBiology of Blood and Marrow Transplantation 9:151-156 (2003