Can forecasting performance be improved by considering the steady state? An application to Swedish inflation and interest rate

This paper investigates whether the forecasting performance of Bayesian autoregressive and vector autoregressive models can be improved by incorporating prior beliefs on the steady state of the time series in the system. Traditional methodology is compared to the new framework—in which a mean‐adjusted form of the models is employed—by estimating the models on Swedish inflation and interest rate data from 1980 to 2004. Results show that the out‐of‐sample forecasting ability of the models is practically unchanged for inflation but significantly improved for the interest rate when informative prior distributions on the steady state are provided. The findings in this paper imply that this new methodology could be useful since it allows us to sharpen our forecasts in the presence of potential pitfalls such as near unit root processes and structural breaks, in particular when relying on small samples. Copyright © 2008 John Wiley & Sons, Ltd.     

How helpful are spatial effects in forecasting the growth of Chinese provinces?

In this paper, we make multi‐step forecasts of the annual growth rates of the real gross regional product (GRP) for each of the 31 Chinese provinces simultaneously. Beside the usual panel data models, we use panel models that explicitly account for spatial dependence between the GRP growth rates. In addition, the possibility of spatial effects being different for different groups of provinces (Interior and Coast) is allowed for. We find that both pooling and accounting for spatial effects help substantially to improve the forecast performance compared to the benchmark models estimated for each of the provinces separately. It is also shown that the effect of accounting for spatial dependence is even more pronounced at longer forecasting horizons (the forecast accuracy gain as measured by the root mean squared forecast error is about 8% at the 1‐year horizon and exceeds 25% at the 13‐ and 14‐year horizons). Copyright © 2010 John Wiley & Sons, Ltd.     

Real‐time or current vintage: does the type of data matter for forecasting and model selection?

In this paper we investigate the impact of data revisions on forecasting and model selection procedures. A linear ARMA model and nonlinear SETAR model are considered in this study. Two Canadian macroeconomic time series have been analyzed: the real‐time monetary aggregate M3 (1977–2000) and residential mortgage credit (1975–1998). The forecasting method we use is multi‐step‐ahead non‐adaptive forecasting. Copyright © 2008 John Wiley & Sons, Ltd.     

Can consumer sentiment and its components forecast Australian GDP and consumption?

This paper examines whether the disaggregation of consumer sentiment data into its sub‐components improves the real‐time capacity to forecast GDP and consumption. A Bayesian error correction approach augmented with the consumer sentiment index and permutations of the consumer sentiment sub‐indices is used to evaluate forecasting power. The forecasts are benchmarked against both composite forecasts and forecasts from standard error correction models. Using Australian data, we find that consumer sentiment data increase the accuracy of GDP and consumption forecasts, with certain components of consumer sentiment consistently providing better forecasts than aggregate consumer sentiment data. Copyright © 2009 John Wiley & Sons, Ltd.     

A place for pragmatism in the dynamics of reason?

In Dynamics of Reason Michael Friedman proposes a kind of synthesis between the neokantianism of Ernst Cassirer, the logical empiricism of Rudolf Carnap, and the historicism of Thomas Kuhn. Cassirer and Carnap are to take care of the Kantian legacy of modern philosophy of science, encapsulated in the concept of the relativized a priori and the globally rational or continuous evolution of scientific knowledge, while Kuhn’s role is to ensure that the historicist character of scientific knowledge is taken seriously. More precisely, Carnapian linguistic frameworks, guarantee that the evolution of science proceeds in a rational manner locally, while Cassirer’s concept of an internally defined conceptual convergence of empirical theories provides the means to maintain the global continuity of scientific reason. In this paper it is argued that Friedman’s Neokantian account of scientific reason based on the concept of the relativized a priori underestimates the pragmatic aspects of the dynamics of scientific reason. To overcome this shortcoming, I propose to reconsider C.I. Lewis’s account of a pragmatic priori, recently modernized and elaborated by Hasok Chang. This may be considered as a first step to a dynamics of an embodied reason, less theoretical and more concrete than Friedman’s Neokantian proposal.     

Prostacyclin-like activity of endothelium and subendothelium - important for atherosclerosis?

Morphological control of Moncada's bioassay for prostacyclin (PG I2) activity measurement shows that the activity depends not only on endothelium, but in important amounts on subendothelial tissue too. Therefore, it can be concluded that platelet thrombus formation after endothelial cell injury does not depend only on the PG I2-producing ability of the tissue.     

Cerivastatin: a cellular and molecular drug for the future?

The 'statin story' began in 1987 when the first-generation, fungal HMG-CoA reductase inhibitor lovastatin received FDA approval in the USA. Ten years later, the sixth compound of this class came onto the world market - the fully synthetic statin cerivastatin. A number of clinical studies had confirmed its high pharmacological efficacy, its excellent pharmacokinetic properties with fast and nearly complete absorption after oral uptake, a linear kinetic over a broad concentration range, and its favorable safety profile. The greatest advantages, of cerivastatin, however, are its lipophilicity, its high bioavailability of about 60% after oral application and its potency at 100-fold lower doses compared to other lipophilic statins. Nevertheless, the most exciting findings are certainly its non-lipid-related, pleiotropic effects at the cellular and molecular level. Statin therapy was also found to reduce mortality in cases where cholesterol levels or atherosclerotic plaque formation remained unaltered. However, cerivastatin improves endothelial dysfunction, possesses anti-inflammatory, antioxidant, anticoagulant, antithrombotic, antiproliferative, plaque-stabilizing, immunmodulatory, and angiogenic effects, and may even prevent tumor growth, Alzheimer's disease, and osteoporosis. Most of these effects seem to be based on the inhibition of isoprenoid synthesis. Although cerivastatin is no longer on the market because of some problematic side effects, it could be one of the most potent cellular and molecular drugs for the future. Received 29 May 2002; received after revision 23 August 2002; accepted 26 August 2002 RID="*" ID="*"Corresponding author.     

Glycine receptors and glycine transporters: targets for novel analgesics?

Glycinergic neurotransmission has long been known for its role in spinal motor control. During the last two decades, additional functions have become increasingly recognized—among them is a critical contribution to spinal pain processing. Studies in rodent pain models provide proof-of-concept evidence that enhancing inhibitory glycinergic neurotransmission reduces chronic pain symptoms. Apparent strategies for pharmacological intervention include positive allosteric modulators of glycine receptors and modulators or inhibitors of the glial and neuronal glycine transporters GlyT1 and GlyT2. These prospects have led to drug discovery efforts in academia and in industry aiming at compounds that target glycinergic neurotransmission with high specificity. Available data show promising analgesic efficacy. Less is currently known about potential unwanted effects but the presence of glycinergic innervation in CNS areas outside the nociceptive system prompts for a careful evaluation not only of motor function, but also of potential respiratory impairment and addictive properties.     

A new cellular function for peroxisomes related to oxygen free radicals?

Summary Although in cell biology peroxisomes are still young organelles, it is becoming increasingly clear that they are involved in important cellular functions. Recent results have indicated the presence of the metalloenzyme superoxide dismutase in peroxisomes and the production of superoxide free radicals (O ₂ ^– ) in these oxidative organelles. These findings, together with other experimental evidence, point towards the existence of new roles for peroxisomes in cellular active oxygen metabolism, something that has a potential impact in multiple areas of cell biology, particularly in biochemistry and biomedicine.     

Mesenchymal stem cells or cardiac progenitors for cardiac repair? A comparative study

In the past, clinical trials transplanting bone marrow–derived mononuclear cells reported a limited improvement in cardiac function. Therefore, the search for stem cells leading to more successful stem cell therapies continues. Good candidates are the so-called cardiac stem cells (CSCs). To date, there is no clear evidence to show if these cells are intrinsic stem cells from the heart or mobilized cells from bone marrow. In this study we performed a comparative study between human mesenchymal stem cells (hMSCs), purified c-kit⁺ CSCs, and cardiosphere-derived cells (CDCs). Our results showed that hMSCs can be discriminated from CSCs by their differentiation capacity towards adipocytes and osteocytes and the expression of CD140b. On the other hand, cardiac progenitors display a greater cardiomyogenic differentiation capacity. Despite a different isolation protocol, no distinction could be made between c-kit⁺ CSCs and CDCs, indicating that they probably derive from the same precursor or even are the same cells.     

D2A sequence of the urokinase receptor induces cell growth through αvβ3 integrin and EGFR

The urokinase receptor (uPAR) stimulates cell proliferation by forming a macromolecular complex with αvβ3 integrin and the epidermal growth factor receptor (EGFR, ErbB1 or HER1) that we name the uPAR proliferasome. uPAR transactivates EGFR, which in turn mediates uPAR-initiated mitogenic signal to the cell. EGFR activation and EGFR-dependent cell growth are blocked in the absence of uPAR expression or when uPAR activity is inhibited by antibodies against either uPAR or EGFR. The mitogenic sequence of uPAR corresponds to the D2A motif present in domain 2. NMR analysis revealed that D2A synthetic peptide has a particular three-dimensional structure, which is atypical for short peptides. D2A peptide is as effective as EGF in promoting EGFR phosphorylation and cell proliferation that were inhibited by AG1478, a specific inhibitor of the tyrosine kinase activity of EGFR. Both D2A and EGF failed to induce proliferation of NR6-EGFR-K721A cells expressing a kinase-defective mutant of EGFR. Moreover, D2A peptide and EGF phosphorylate ERK demonstrating the involvement of the MAP kinase signalling pathway. Altogether, this study reveals the importance of sequence D2A of uPAR, and the interdependence of uPAR and EGFR.     

ΛCDM and MOND: A debate about models or theory?

The debate between ΛCDM and MOND is often cast in terms of competing gravitational theories. However, recent philosophical discussion suggests that the ΛCDM–MOND debate demonstrates the challenges of multiscale modeling in the context of cosmological scales. I extend this discussion and explore what happens when the debate is thought to be about modeling rather than about theory, offering a model-focused interpretation of the ΛCDM–MOND debate. This analysis shows how a model-focused interpretation of the debate provides a better understanding of challenges associated with extension to a different scale or domain, which are tied to commitments about explanatory fit.     

Forecast Combination for Euro Area Inflation: A Cure in Times of Crisis?

The period of extraordinary volatility in euro area headline inflation starting in 2007 raised the question whether forecast combination methods can be used to hedge against bad forecast performance of single models during such periods and provide more robust forecasts. We investigate this issue for forecasts from a range of short‐term forecasting models. Our analysis shows that there is considerable variation of the relative performance of the different models over time. To take that into account we suggest employing performance‐based forecast combination methods—in particular, one with more weight on the recent forecast performance. We compare such an approach with equal forecast combination that has been found to outperform more sophisticated forecast combination methods in the past, and investigate whether it can improve forecast accuracy over the single best model. The time‐varying weights assign weights to the economic interpretations of the forecast stemming from different models. We also include a number of benchmark models in our analysis. The combination methods are evaluated for HICP headline inflation and HICP excluding food and energy. We investigate how forecast accuracy of the combination methods differs between pre‐crisis times, the period after the global financial crisis and the full evaluation period, including the global financial crisis with its extraordinary volatility in inflation. Overall, we find that forecast combination helps hedge against bad forecast performance and that performance‐based weighting outperforms simple averaging. Copyright © 2017 John Wiley & Sons, Ltd.     

Plasma enteroglucagon,peptide YY and gastrin in rats deprived of luminal nutrition,and after urogastrone-EGF administration. A proliferative role for PYY in the intestinal epithelium?

Intestinal tissue mass was significantly reduced throughout the gastrointestinal tract (p<0.001) of=" intravenously=" fed=" (tpn)=" rats.=" urogastrone-epidermal=" growth=" factor,=" (uro-egf),=" reversed=" these=" changes.=" although=" plasma=" enteroglucagon=" and=" gastrin=" levels=" showed=" a=" small=" increase=" with=" uro-egf,=" this=" was=" far=" less=" than=" the=" gut=" tissue=" weight=" change,=" suggesting=" that=" it=" was=" unlikely=" that=" they=" were=" involved=" in=" modulating=" the=" proliferative=" response=" of=" the=" intestine=" to=" uro-egf.=" peptide=" tyrosine=" tyrosine=" (pyy)=" levels=" were=" however=" significantly=" increased=" by=" uro-egf,=" indicating=" that=" pyy=" may=" possibly=" have=" a=" role=" in=" the=" modulation=" of=" intestinal=" cell=">We thank the Cancer Research Campaign for their financial assistance and acknowledge the technical assistance of Mr W. Lenton.     

On glioblastoma and the search for a cure: where do we stand?

Although brain tumours have been documented and recorded since the nineteenth century, 2016 marked 90 years since Percival Bailey and Harvey Cushing coined the term “glioblastoma multiforme”. Since that time, although extensive developments in diagnosis and treatment have been made, relatively little improvement on prognosis has been achieved. The resilience of GBM thus makes treating this tumour one of the biggest challenges currently faced by neuro-oncology. Aggressive and robust development, coupled with difficulties of complete resection, drug delivery and therapeutic resistance to treatment are some of the main issues that this nemesis presents today. Current treatments are far from satisfactory with poor prognosis, and focus on palliative management rather than curative intervention. However, therapeutic research leading to developments in novel treatment stratagems show promise in combating this disease. Here we present a review on GBM, looking at the history and advances which have shaped neurosurgery over the last century that cumulate to the present day management of GBM, while also exploring future perspectives in treatment options that could lead to new treatments on the road to a cure.     

What is mechanistic evidence,and why do we need it for evidence-based policy?

It has recently been argued that successful evidence-based policy should rely on two kinds of evidence: statistical and mechanistic. The former is held to be evidence that a policy brings about the desired outcome, and the latter concerns how it does so. Although agreeing with the spirit of this proposal, we argue that the underlying conception of mechanistic evidence as evidence that is different in kind from correlational, difference-making or statistical evidence, does not correctly capture the role that information about mechanisms should play in evidence-based policy. We offer an alternative account of mechanistic evidence as information concerning the causal pathway connecting the policy intervention to its outcome. Not only can this be analyzed as evidence of difference-making, it is also to be found at any level and is obtainable by a broad range of methods, both experimental and observational. Using behavioral policy as an illustration, we draw the implications of this revised understanding of mechanistic evidence for debates concerning policy extrapolation, evidence hierarchies, and evidence integration.