The last decade has brought dramatic changes in the way that researchers analyze economic and financial time series. This book synthesizes these recent advances and makes them accessible to ...first-year graduate students. James Hamilton provides the first adequate text-book treatments of important innovations such as vector autoregressions, generalized method of moments, the economic and statistical consequences of unit roots, time-varying variances, and nonlinear time series models. In addition, he presents basic tools for analyzing dynamic systems (including linear representations, autocovariance generating functions, spectral analysis, and the Kalman filter) in a way that integrates economic theory with the practical difficulties of analyzing and interpreting real-world data. Time Series Analysis fills an important need for a textbook that integrates economic theory, econometrics, and new results. The book is intended to provide students and researchers with a self-contained survey of time series analysis. It starts from first principles and should be readily accessible to any beginning graduate student, while it is also intended to serve as a reference book for researchers.
Dupilumab is an IL-4 receptor α mAb inhibiting signaling of IL-4 and IL-13, key drivers of type 2–driven inflammation, as demonstrated by its efficacy in patients with atopic/allergic diseases.
This ...placebo-controlled, double-blind trial (NCT01979016) evaluated the efficacy, safety, and effects of dupilumab on molecular/cellular lesional and nonlesional skin phenotypes and systemic type 2 biomarkers of patients with moderate-to-severe atopic dermatitis (AD).
Skin biopsy specimens and blood were evaluated from 54 patients randomized 1:1 to weekly subcutaneous doses of 200 mg of dupilumab or placebo for 16 weeks.
Dupilumab (vs placebo) significantly improved clinical signs and symptoms of AD, was well tolerated, and progressively shifted the lesional transcriptome toward a nonlesional phenotype (weeks 4–16). Mean improvements in a meta-analysis–derived AD transcriptome (genes differentially expressed between lesional and nonlesional skin) were 68.8% and 110.8% with dupilumab and −10.5% and 55.0% with placebo (weeks 4 and 16, respectively; P < .001). Dupilumab significantly reduced expression of genes involved in type 2 inflammation (IL13, IL31, CCL17, CCL18, and CCL26), epidermal hyperplasia (keratin 16 K16 and MKi67), T cells, dendritic cells (ICOS, CD11c, and CTLA4), and TH17/TH22 activity (IL17A, IL-22, and S100As) and concurrently increased expression of epidermal differentiation, barrier, and lipid metabolism genes (filaggrin FLG, loricrin LOR, claudins, and ELOVL3). Dupilumab reduced lesional epidermal thickness versus placebo (week 4, P = .001; week 16, P = .0002). Improvements in clinical and histologic measures correlated significantly with modulation of gene expression. Dupilumab also significantly suppressed type 2 serum biomarkers, including CCL17, CCL18, periostin, and total and allergen-specific IgEs.
Dupilumab-mediated inhibition of IL-4/IL-13 signaling through IL-4 receptor α blockade significantly and progressively improved disease activity, suppressed cellular/molecular cutaneous markers of inflammation and systemic measures of type 2 inflammation, and reversed AD-associated epidermal abnormalities.
Measuring global economic activity Hamilton, James D.
Journal of applied econometrics (Chichester, England),
April/May 2021, Letnik:
36, Številka:
3
Journal Article
Recenzirano
Summary
A number of economic studies have used a proxy for world real economic activity derived from shipping costs. This measure turns out to depend on a normalization that has substantive ...consequences, of which users of the index had been unaware prior to this paper. This paper further evaluates this and alternative measures in terms of treatment of trends, coherence with world output, and correlation with commodity prices. I conclude that measures derived from world industrial production offer a better indicator of global real economic activity.
This paper explores similarities and differences between the run-up of oil prices in 2007–08 and earlier oil price shocks, looking at what caused these price increases and what effects they had on ...the economy. Whereas previous oil price shocks were primarily caused by physical disruptions of supply, the price run-up of 2007–08 was caused by strong demand confronting stagnating world production. Although the causes were different, the consequences for the economy appear to have been similar to those observed in earlier episodes, with significant effects on consumption spending and purchases of domestic automobiles in particular. Absent those declines, it is unlikely that the period 2007Q4–2008Q3 would have been characterized as one of recession for the United States. This episode should thus be added to the list of U.S. recessions to which oil prices appear to have made a material contribution.
This paper makes the following original contributions to the literature. (i) We develop a simpler analytical characterization and numerical algorithm for Bayesian inference in structural vector ...autoregressions (VARs) that can be used for models that are overidentified, just-identified, or underidentified. (ii) We analyze the asymptotic properties of Bayesian inference and show that in the underidentified case, the asymptotic posterior distribution of contemporaneous coefficients in an n-variable VAR is confined to the set of values that orthogonalize the population variance-covariance matrix of ordinary least squares residuals, with the height of the posterior proportional to the height of the prior at any point within that set. For example, in a bivariate VAR for supply and demand identified solely by sign restrictions, if the population correlation between the VAR residuals is positive, then even if one has available an infinite sample of data, any inference about the demand elasticity is coming exclusively from the prior distribution. (iii) We provide analytical characterizations of the informative prior distributions for impulse-response functions that are implicit in the traditional sign-restriction approach to VARs, and we note, as a special case of result (ii), that the influence of these priors does not vanish asymptotically. (iv) We illustrate how Bayesian inference with informative priors can be both a strict generalization and an unambiguous improvement over frequentist inference in just-identified models. (v) We propose that researchers need to explicitly acknowledge and defend the role of prior beliefs in influencing structural conclusions and we illustrate how this could be done using a simple model of the U.S. labor market.
The adoption of immersive virtual reality (I-VR) as a pedagogical method in education has challenged the conceptual definition of what constitutes a learning environment. High fidelity graphics and ...immersive content using head-mounted-displays (HMD) have allowed students to explore complex subjects in a way that traditional teaching methods cannot. Despite this, research focusing on learning outcomes, intervention characteristics, and assessment measures associated with I-VR use has been sparse. To explore this, the current systematic review examined experimental studies published since 2013, where quantitative learning outcomes using HMD based I-VR were compared with less immersive pedagogical methods such as desktop computers and slideshows. A literature search yielded 29 publications that were deemed suitable for inclusion. Included papers were quality assessed using the Medical Education Research Study Quality Instrument (MERSQI). Most studies found a significant advantage of utilising I-VR in education, whilst a smaller number found no significant differences in attainment level regardless of whether I-VR or non-immersive methods were utilised. Only two studies found clear detrimental effects of using I-VR. However, most studies used short interventions, did not examine information retention, and were focused mainly on the teaching of scientific topics such as biology or physics. In addition, the MERSQI showed that the methods used to evaluate learning outcomes are often inadequate and this may affect the interpretation of I-VR’s utility. The review highlights that a rigorous methodological approach through the identification of appropriate assessment measures, intervention characteristics, and learning outcomes is essential to understanding the potential of I-VR as a pedagogical method.
We develop a simple model of futures arbitrage that implies that if purchases by commodity index funds influence futures prices, then the notional positions of the index investors should help predict ...excess returns in these contracts. We find no evidence that the positions of index traders in agricultural contracts as identified by the Commodity Futures Trading Commission can help predict returns on the near futures contracts. Although there is some support that these positions might help predict changes in oil futures prices over 2006–2009, the relation breaks down out of sample.
Muscle protein breakdown (MPB) is an important metabolic component of muscle remodeling, adaptation to training, and increasing muscle mass. Degradation of muscle proteins occurs via the integration ...of three main systems—autophagy and the calpain and ubiquitin-proteasome systems. These systems do not operate independently, and the regulation is complex. Complete degradation of a protein requires some combination of the systems. Determination of MPB in humans is technically challenging, leading to a relative dearth of information. Available information on the dynamic response of MPB primarily comes from stable isotopic methods with expression and activity measures providing complementary information. It seems clear that resistance exercise increases MPB, but not as much as the increase in muscle protein synthesis. Both hyperaminoacidemia and hyperinsulinemia inhibit the post-exercise response of MPB. Available data do not allow a comprehensive examination of the mechanisms behind these responses. Practical nutrition recommendations for interventions to suppress MPB following exercise are often made. However, it is likely that some degree of increased MPB following exercise is an important component for optimal remodeling. At this time, it is not possible to determine the impact of nutrition on any individual muscle protein. Thus, until we can develop and employ better methods to elucidate the role of MPB following exercise and the response to nutrition, recommendations to optimize post exercise nutrition should focus on the response of muscle protein synthesis. The aim of this review is to provide a comprehensive examination of the state of knowledge, including methodological considerations, of the response of MPB to exercise and nutrition in humans.
This paper reviews some of the literature on the macroeconomic effects of oil price shocks with a particular focus on possible nonlinearities in the relation and recent new results obtained by Kilian ...and Vigfusson http://www-personal.umich/~lkilian/kvsubmission.pdf (2009).