Evaluating Measures of Core Inflation

Since the Bank of Canada adopted inflation targeting in 1991, it has focused on a measure of core inflation as a shorter-term guide for monetary policy. When the targets were renewed in 2001, the Bank adopted CPIX as its measure of core inflation because of the advantages it offered. Leflèche and Armour review the experience with CPIX and whether the criteria used to select it in 2001 still favour the measure today. They describe the various measures of core inflation monitored by the Bank and evaluate them on the basis of the volatility of the components, the volatility of the core measures themselves, absence of bias relative to total CPI, predictive power, and certain practical criteria, including timeliness and credibility. They conclude that CPIX still satisfies all the empirical and practical criteria.

Feedback Rules for Inflation Control: An Overview of Recent Literature

Feedback rules are rules aimed at guiding policy-makers as they face the problem of keeping inflation close to a desired path without causing variability elsewhere in the economy. These rules link short-term interest rates, controlled by the central bank, to the rate of inflation and/or its deviation from a target rate. The authors describe the most popular types of feedback rules and review some simulation results.

Science Pipelines for the Square Kilometre Array

The Square Kilometre Array (SKA) will be both the largest radio telescope ever constructed and the largest Big Data project in the known Universe. The first phase of the project will generate on the order of 5 zettabytes of data per year. A critical task for the SKA will be its ability to process data for science, which will need to be conducted by science pipelines. Together with polarization data from the LOFAR Multifrequency Snapshot Sky Survey (MSSS), we have been developing a realistic SKA-like science pipeline that can handle the large data volumes generated by LOFAR at 150 MHz. The pipeline uses task-based parallelism to image, detect sources, and perform Faraday Tomography across the entire LOFAR sky. The project thereby provides a unique opportunity to contribute to the technological development of the SKA telescope, while simultaneously enabling cutting-edge scientific results. In this paper, we provide an update on current efforts to develop a science pipeline that can enable tight constraints on the magnetised large-scale structure of the Universe.Comment: Published in Galaxies, as part of a Special Issue on The Power of Faraday Tomograph

Revealing what is distinct by recognising what is common: distinguishing between complex PTSD and Borderline Personality Disorder symptoms using bifactor modelling

Background: Despite concerns of conceptual similarity, increasing evidence supports the discriminant validity of Complex Posttraumatic Stress Disorder (CPTSD) and Borderline Personality Disorder (BPD). However, all studies to date have assumed a categorical model of psychopathology. In contrast, dimensional models of psychopathology, such as the Hierarchical Taxonomy of Psychopathology model (i.e. HiTOP model), recognise shared vulnerability across supposedly discrete disorders. Accounting for shared vulnerability between CPTSD and BPD symptoms may help to better reveal what is unique about these constructs. Objective: To identify the distinct and shared features of CPTSD and BPD via the application of dimensional modelling procedures. Method: Confirmatory bifactor and confirmatory factor analysis were employed to identify the optimal latent structure of CPTSD and BPD symptoms amongst a convenience sample of Israeli adults (N = 617). Additionally, structural equation modelling was used to identify risk factors associated with these constructs. Results: The latent structure of CPTSD and BPD symptoms was best explained by a bifactor model including one ‘general’ factor (i.e. vulnerability to all symptoms) and three ‘specific’ correlated factors (i.e. vulnerability to PTSD, DSO, and BPD symptoms, respectively). CPTSD symptoms were more readily distinguished from the general factor whereas BPD symptoms were not as easily distinguished from the general factor. CPTSD symptoms reflecting a negative self-concept and BPD symptoms reflecting an alternating self-concept were the most distinctive features of CPTSD and BPD relative to the general factor, respectively. Most of the risk factors were associated with the general vulnerability factor, consistent with the predictions of dimensional models of psychopathology regarding shared risk across supposedly distinct psychiatric constructs. Conclusion: Consistent with a dimensional model of psychopathology, CPTSD and BPD shared a common latent structure but were still distinguishable. CPTSD and BPD symptoms may be most effectively distinguished based on the phenomenology of self-concept symptoms

From Mantle to Motzfeldt : a genetic model for syenite-hosted Ta,Nb-mineralisation

This research summarises many years of field and lab studies on the area, but the most recent work (2016) has received funding from the European Union’s Horizon 2020 research and innovation programme (grant agreement No 689909).A genetic model for the Motzfeldt Tantalum-Niobium-rich syenite in south-west Greenland, considered to be one of the world’s largest Ta prospects, is presented. The Motzfeldt primary magma formed early in regional Gardar (1273 ± 6 Ma) rifting. Isotope signatures indicate that the Hf had multiple sources involving juvenile Gardar Hf mixed with older (Palaeoproterozoic or Archaean) Hf. We infer that other High Field Strength Elements (HFSE) similarly had multiple sources. The magma differentiated in the crust and ascended before emplacement at the regional unconformity between Ketilidian basement and Eriksfjord supracrustals. The HFSE-rich magmas crystallised Ta-rich pyrochlore which formed pyrochlore-rich crystal mushes, and it is these pyrochlore-rich horizons, rich in Ta and Nb, that are the focus of exploration. The roof zone chilled and repeated sheeting at the roof provided a complex suite of cross-cutting syenite variants, including pyrochlore microsyenite, in a ‘Hot Sheeted Roof’ model. The area was subject to hydrothermal alteration which recrystallized alkali feldspar to coarse perthite and modified the mafic minerals to hematite, creating the friable and striking pink-nature of the Motzfeldt Sø Centre. Carbon and oxygen isotope investigation of carbonate constrains fluid evolution and shows that carbonate is primarily mantle-derived but late-stage hydrothermal alteration moved the oxygen isotopes towards more positive values (up to 21‰). The hydrothermal fluid was exceptionally fluorine-rich and mobilised many elements including U and Pb but did not transport HFSE such as Ta, Hf and Nb. Although the U and Pb content of the pyrochlore was enhanced by the fluid, the HFSE contents remained unchanged and therefore Hf isotopes were unaffected by fluid interaction. While the effect on hydrothermal alteration on the visual appearance of the rock is striking, magmatic processes concentrated HFSE including Ta and the hydrothermal phase has not altered the grade. Exploration for HFSE mineralisation commonly relies on airborne radiometric surveying which is particularly sensitive to the presence of U, Th. A crucial lesson from Motzfeldt is that the best target is unaltered pyrochlore which was identified less easily by radiometric survey. Careful petrological/mineral studies are necessary before airborne survey data can be fully interpreted.PreprintPostprintPeer reviewe

Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study

Introduction: The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures. Methods: In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025. Findings: Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2–6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p<0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5–5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p<0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4–10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p<0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32–4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP >5mg/L, OR 3·55 [1·23–11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation. Interpretation: After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification

Taylor Rules in the Quarterly Projection Model

In recent years, there has been a lot of interest in Taylor-type rules. Evidence in the literature suggests that Taylor-type rules are optimal in a number of models and are fairly robust across different models. The reaction function in the Bank of Canada's Quarterly Projection Model (QPM) is an inflation-forecast-based (IFB) rule. A number of studies have suggested, however, that the optimality of IFB rules is very model-specific. Given this and concerns about model uncertainty, it seems logical to assess the performance of Taylor-type reaction functions in QPM. Therefore, we compare QPM's IFB rule with a simple Taylor rule as well as with two rules that include open-economy elements. Overall, our results suggest that Taylor-type rules do not perform well in QPM compared with the base-case IFB rule, since they are associated with significantly higher variabilities of inflation, output, and interest rates. However, of the Taylor-type rules considered, we find that a simple rule with a coefficient of 2 on the contemporaneous inflation gap (versus 0.5 in Taylor's original rule) and a coefficient of 0.5 on the output gap is the most appropriate. Furthermore, the gains from using open-economy rules seem to be limited.Monetary policy framework; Uncertainty and monetary policy; Economic models